Carbon emission accounting method for eucalyptus felling, residue treatment and production and operation processes

Abstract

The invention relates to the technical field of forestry carbon neutralization, and discloses a eucalyptus felling, residue treatment and production operation process carbon emission accounting method, which comprises the following steps of: dividing sub-stages in a life cycle of eucalyptus felling, residue treatment and production operation, and determining a system boundary and a functional unit of a carbon footprint; determining a carbon emission list of each sub-stage according to technical regulations of eucalyptus felling, operation and residue treatment and actual production information, performing carbon emission list analysis in a life cycle in the eucalyptus production and operation process, and determining input and output lists of each sub-stage; determining a calculation method, a distribution program, a data requirement and an emission factor in each sub-stage; and constructing a carbon emission accounting model of each sub-stage by using an emission factor method, and obtaining the carbon footprint of eucalyptus production and operation by using the carbon emission accounting model of each sub-stage. The method is designed for the operation and production process of eucalyptus, and aims to accurately evaluate the carbon footprint in the whole eucalyptus product life cycle.

Description

Technical Field

[0001] The present invention relates to the technical field of forestry carbon neutrality, and in particular to a method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management. Background Art

[0002] In recent years, due to the increasing impact of extreme climate caused by the greenhouse effect on human life, all walks of life around the world have begun to seek more low-carbon and sustainable materials to replace today's materials; wood, as a natural resource with carbon dioxide absorption and renewable capacity, is used by more and more industries, resulting in a significant increase in the use of wood. Eucalyptus is a plant of the Myrtaceae family, Eucalyptus, Cupia, and Corymborum, with the characteristics of fast growth and strong resistance. Compared with other artificial forest tree species, eucalyptus grows faster, has low environmental requirements, can grow in harsh weather conditions, can withstand high temperatures and a certain degree of drought, and has high economic value and forestation efficiency; usually, eucalyptus can grow from 10 meters to 60 meters within 10 years. In addition to its fast growth rate, eucalyptus is also a very sustainable seedling in the right area. After felling, some eucalyptus forests can be sprouted on the basis of the original wooden piles to avoid uprooting the felled piles after felling, so as to achieve the purpose of sustainable management.

[0003] Due to different production and management objectives, there are differences in the management methods of eucalyptus plantations, which directly affect the methods of logging and residue treatment, and thus affect carbon emissions; different management methods will lead to differences in carbon emissions, such as intensive planting may increase carbon emissions from logging and transportation, while natural regeneration may reduce these activities. Direct carbon emissions generated by logging activities mainly come from fuel consumption of mechanical operations (such as logging machines and transport vehicles). The fuel consumption of logging machinery and transportation tools is quantified to determine direct carbon emissions; logging residues can be treated by composting, incineration or as biomass energy. Different treatment methods will produce different degrees of carbon emissions. For example, incineration will produce a large amount of carbon dioxide, while composting may produce greenhouse gases such as methane. Evaluate the contribution of different residue treatment methods to carbon emissions, including methane produced by composting and carbon dioxide produced by incineration. By considering the differences in logging and residue treatment in different production and management processes, calculate the carbon emissions generated by the production and management process.

[0004] At present, eucalyptus plantations are divided into short-cutting raw material plantations and medium- and large-diameter timber plantations according to different production and management purposes of eucalyptus. Short-cutting raw material plantations are usually established to produce fiber raw materials, mainly serving the pulp, papermaking and biomass energy industries. This type of plantation is characterized by a short growth cycle. Generally, eucalyptus can reach the harvest standard within 5 to 10 years. Through high-density planting and scientific management, a high biomass accumulation per unit area can be achieved, thereby ensuring a stable supply of fiber raw materials. In addition, due to the fast renewal speed of short-cutting plantations, they can quickly respond to changes in market demand and have relatively little impact on the environment, which is conducive to sustainable development. In contrast, medium- and large-diameter timber plantations focus more on cultivating high-quality wood resources for use in industries such as construction and furniture manufacturing that have high requirements for wood size and quality. This type of plantation has a long growth cycle and often takes more than 20 years to reach maturity. In order to obtain wood with larger diameter and better quality, the planting density and management methods of medium and large diameter timber plantations are different from those of short-felling raw material forests. More attention is paid to the spacing between trees, giving each tree enough space to grow and ensuring the straightness and strength of the wood.

[0005] Carbon emission accounting has far-reaching significance for forest management. It not only provides a scientific basis to accurately evaluate the actual impact of forest management activities on the ecological environment, but also helps to improve management strategies and enhance the health and productivity of forest ecosystems. Through detailed carbon emission data, policymakers can obtain strong support to fulfill their national environmental protection responsibilities and commitments under international climate agreements.

[0006] In the prior art, Chinese patent CN118333653A introduces a method for calculating carbon cycle and carbon emissions in agricultural ecosystems, which pays special attention to the dynamic monitoring and evaluation of carbon balance during crop planting. It integrates remote sensing technology and ground observation data to establish a comprehensive model to quantify the carbon fixation potential and carbon emissions of farmland under different management measures. Although the patent provides an advanced carbon cycle accounting framework suitable for crop planting, it does not specifically analyze the carbon emission characteristics of economic trees, such as eucalyptus, throughout their life cycle.

[0007] Chinese patent CN118212541A proposes a method for calculating carbon emissions from rice production using remote sensing, which may analyze in detail the carbon footprint of each link from rice planting, growth to harvesting. The patent may introduce a systematic evaluation system to quantify greenhouse gas emissions in the rice production chain, including irrigation, fertilization, pest and disease management, harvesting, and subsequent processing. However, it does not extend to other types of cash crops, such as eucalyptus. In particular, for tree species such as eucalyptus that play an important role in the production of energy and industrial materials, the carbon emission characteristics of the process from planting, tending, harvesting to wood and by-product processing may not be covered accordingly.

[0008] Chinese patent CN118014393 discloses an innovative method and system for carbon footprint accounting specifically for the seedling cultivation stage of economic trees. The patent details the seedling breeding process and divides it into three key sub-stages: breeding of improved varieties, greenhouse cultivation, and field seedling cultivation and seedling rejuvenation. In the accounting process, it further divides various inputs into eight subcategories according to their nature, including energy consumption, fertilizer application, pesticide spraying, experimental reagents, consumable materials, labor costs, transportation activities, and waste disposal, so as to achieve accurate quantification of carbon emissions in the breeding stage. However, it focuses on the starting point of the life cycle of economic trees, and indeed the carbon footprints of the tending management of forest stands, the felling of mature trees, wood processing, and the manufacture and distribution of final products are not included in the accounting scope of this patent; and the carbon emission accounting during the residual material treatment process is not considered.

[0009] To date, there is no existing technology specifically for carbon emission accounting in eucalyptus production and management activities and comprehensive assessment of the carbon footprint of its products. Summary of the invention

[0010] The purpose of the present invention is to provide a method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management processes, which is designed for the management and production process of eucalyptus, and aims to accurately evaluate the carbon footprint of the entire eucalyptus product life cycle. This breakthrough is crucial for the environmental performance evaluation of the eucalyptus industry and participation in the carbon trading market. This application can scientifically and rationally plan the management and operation measures of eucalyptus to ensure that each step is in line with the low-carbon development goals, thereby leading the entire eucalyptus product industry chain to transform in a more environmentally friendly direction. This method not only fills the gap in the prior art, but also lays a solid foundation for the sustainable development of the eucalyptus industry, and is expected to become an important tool for promoting the green economy and addressing climate change.

[0011] In order to achieve the above purpose, the technical solutions adopted are as follows:

[0012] A method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management, including:

[0013] Divide the sub-stages in the life cycle of eucalyptus harvesting, residue handling and production management and determine the system boundaries and functional units of carbon footprint;

[0014] According to the technical regulations and actual production information of eucalyptus felling, management and residue treatment, determine the carbon emission inventory of each sub-stage, analyze the carbon emission inventory of the eucalyptus production and management process within the life cycle, and determine the input and output inventory of each sub-stage;

[0015] Determine the calculation methods, allocation procedures, data requirements and emission factors within each sub-phase;

[0016] The emission factor method is used to construct the carbon emission accounting model for each sub-stage, and the carbon footprint of eucalyptus production and operation is obtained using the carbon emission accounting model for each sub-stage.

[0017] Preferably, the sub-stages divided within the life cycle of eucalyptus felling, residue treatment and production and management include a production and management sub-stage, a fallen material treatment sub-stage and a felling sub-stage.

[0018] Preferably, the production and management stage includes the forest land preparation stage, the land preparation stage, the afforestation stage, the weeding stage, the fertilization stage and the pest and disease treatment stage; wherein:

[0019] The forest land preparation stage includes comprehensive clearing, strip clearing or block clearing; wherein the height of the regional shrubs after clearing is less than 20cm;

[0020] The land preparation stage includes backfilling of topsoil, and the backfilling of topsoil includes cleaning, land preparation, hole digging, basal fertilizer application, and backfilling; wherein, the land preparation includes mechanical land preparation and manual land preparation, and the mechanical land preparation refers to the use of mechanical belt reclamation in forest land with a slope of less than 15° to cultivate the soil along a set direction on the afforestation land; the manual land preparation refers to the use of manual digging holes or belt reclamation for land preparation in mountainous areas with a slope of more than 15°, and manual hole digging refers to the use of tools to dig holes of a set size and depth on the afforestation land for planting trees; belt reclamation refers to the cultivation of soil along a set direction in the afforestation area to form a long strip of cultivation belt; basal fertilizer application refers to the fertilizer applied to the soil before or during plant planting; basal fertilizer application and backfilling are carried out simultaneously, and fertilizer is put into the hole when 1 / 3 of the soil is backfilled, and the topsoil is continued to be backfilled until the planting hole is filled;

[0021] The afforestation stage includes two methods: seedling planting or stump cutting and renewal. Among them, seedling planting refers to planting cultivated seedlings into the soil in a predetermined density and layout on a designated land to form an artificial forest; stump cutting and renewal refers to renewing the forest stand on the stumps of felled eucalyptus trees by using the natural germination ability of trees to grow new plants.

[0022] Preferably, the drop processing sub-stage includes a retention stage, a combustion stage and a removal stage; wherein:

[0023] The retention stage refers to retaining litter on the forest land instead of removing it. During the retention process, the goal and strategy of retaining litter are set, and the impact of retained litter on the forest ecosystem is regularly observed to adjust management measures.

[0024] The burning stage refers to burning the forest litter in situ or transporting it to a designated area for burning. During the burning process, environmental risks are assessed and a burning plan is formulated; a firebreak is opened around the designated area and combustibles are removed; the litter is ignited, and after the burning is completed, the designated area is checked for any risk of re-ignition. If there is no risk of re-ignition in the designated area, the ashes are collected and used as a soil conditioner or fertilizer;

[0025] The removal stage refers to collecting and removing the litter from the forest area, including: collecting the litter and transporting the collected litter to the stacking area.

[0026] Preferably, the felling sub-stage refers to the thinning or clear felling after the trees grow to a set stage according to the management objectives and the growth conditions of the trees; wherein:

[0027] In short-rotation industrial raw material forests, the clear-cut method is adopted to cut down mature forests that meet the needs, and the damaged trees are only cut down when pests, diseases or natural disasters occur;

[0028] In medium and large diameter timber plantations, the tending thinning method is adopted. When the initial planting density is reached, the tending thinning is carried out according to the actual growth of the forest stand. During the tending thinning process, the dominant trees with normal growth and development and suitable for cultivation are retained, and the individuals with poor growth and development, bent trunks, bark injuries, and severe windbreaks are cut off.

[0029] The thinning method starts 2 to 4 years after afforestation, when the forest canopy density reaches above 0.8, the trees are strongly differentiated, and the suppressed trees account for 30% to 40% of the total number of trees, thinning begins; the thinning intensity does not exceed 30% of the number of trees, and the canopy density after felling is controlled at 0.6;

[0030] The clear felling begins 8 to 15 years after afforestation. The height of the stumps after manual felling is controlled at 7 to 10 cm; the height of the stumps after mechanical felling is controlled at 5 to 7 cm.

[0031] Preferably, the carbon emissions generated by the production and operation sub-stage are calculated by the following method: the carbon footprint of the energy input of the machinery used in the production and operation sub-stage is calculated based on the following formula:

[0032] E 能源1 =(M 柴油1 ×EF 柴油1)

[0033]

[0034] V 机械m =T m1 ×U m1

[0035] Among them, E 能源1 M represents the carbon footprint of energy input used in the machinery in the production and operation sub-stage; 柴油1 The mass of diesel consumed by the machinery used in the production and operation sub-stage, EF 柴油1 is the emission factor for diesel, ρ 柴油1 is the average density of diesel used, m is the serial number of the machinery used in the production and operation sub-stage, mi is the total number of machinery used in the production and operation sub-stage, V 机械m is the diesel consumption of the mth machine in the production and operation sub-stage, T m1 The time that the mechanical work is spent on the production and operation sub-stage, in hours (h), U m1 The fuel consumption per unit time of the machinery in the production and operation sub-stage, in L / h;

[0036] The carbon footprint of fertilizer input is calculated based on the following formula:

[0037]

[0038] Among them, E 肥料 represents the carbon footprint of fertilizer input, f represents the sequence number of fertilizer, i represents the total number of fertilizer types, and F f represents the amount of the fth fertilizer applied to each eucalyptus tree, EF f represents the emission factor of the f-th fertilizer, T represents the frequency of application of the f-th fertilizer in the production and operation cycle, and N represents the number of eucalyptus trees per unit area;

[0039] The carbon footprint of pesticide input is calculated based on the following formula:

[0040]

[0041] Among them, E 农药 is the carbon footprint of pesticide input, p is the serial number of the pesticide, pi is the total number of pesticide types, P p is the amount of effective ingredient of the pth pesticide applied per unit area, S p is the total area sprayed with the pth pesticide, EF p is the emission factor of the active ingredient in the pth pesticide;

[0042] The carbon footprint generated by the transportation process in the production and operation sub-stage is calculated based on the following formula:

[0043]

[0044] in,

[0045] M 燃油1 =ρ 燃油1 ×D×C d

[0046] or

[0047] M 燃油1 =ρ 燃油1 ×T1×C t

[0048] in, is the carbon footprint generated during the transportation process, t1 is the vehicle serial number, ti is the total number of vehicles; M 燃油1 is the fuel quality, EF t1 is the emission factor of fuel used by vehicles, ρ 燃油1 is the average density of the fuel used, D is the transportation distance, C d is the fuel consumption per unit distance traveled by the vehicle, T1 is the driving time of the vehicle during transportation, C t is the fuel consumption of the truck per unit time;

[0049] The carbon footprint of human input in the production and operation sub-stage is calculated based on the following formula:

[0050]

[0051] Among them, EF 人力1 is the emission factor of human input in the production and operation sub-stage, r is the activity number per unit area in the production and operation sub-stage, ri is the total number of activities per unit area in the production and operation sub-stage; P r is the number of people involved in the activity with serial number r per unit area in the production and operation sub-stage, T r The number of working days for the activity with time serial number r in the production and operation sub-stage;

[0052] The carbon emissions generated in the production and operation sub-stage are taken as the sum of the carbon footprint of energy input used in machinery, the carbon footprint of fertilizer input, the carbon footprint of pesticide input, the carbon footprint generated in the transportation process of the production and operation sub-stage, and the carbon footprint generated in the human input of the production and operation sub-stage.

[0053] Preferably, the carbon emissions generated by the harvesting sub-stage are calculated by the following method:

[0054] The carbon footprint of energy input during the use of machinery in the harvesting sub-stage is calculated based on the following formula:

[0055]

[0056] V 机械m' =Tm' ×U m'

[0057] in, M' represents the carbon footprint of energy input during the use of machinery in the harvesting sub-stage; 柴油 is the mass of diesel consumed by machinery in the harvesting sub-stage, EF' 柴油 is the emission factor for diesel fuel used in the harvesting sub-phase, ρ' 柴油 is the average density of diesel used in the harvesting sub-stage, m' is the serial number of the machine used in the harvesting sub-stage, m'i is the total number of machines used in the harvesting sub-stage, V 机械m' is the diesel consumption of the m'th machine in the harvesting sub-stage, T m' The time that the machine works in the felling sub-stage, in hours (h), U m' is the fuel consumption per unit time of the machinery in the harvesting sub-stage, in L / h;

[0058] The carbon footprint of the transportation process in the harvesting sub-stage is calculated based on the following formula:

[0059]

[0060] in,

[0061] M′ 燃油 =ρ′ 燃油 ×D′×C′ d

[0062] or

[0063] M′ 燃油 =ρ′ 燃油 ×T′×C′ t

[0064] in, is the carbon footprint generated during the transportation process in the logging sub-stage, M' 燃油 Fuel mass used for transportation during the harvesting sub-phase, EF t' is the emission factor for fuel used in the harvesting sub-phase, ρ' 燃油 is the average density of fuel used in the logging sub-stage, D' is the transportation distance in the logging sub-stage, C' d is the fuel consumption per unit distance of the vehicle in the logging sub-stage, T' is the driving time of the vehicle in the logging sub-stage, and C' t is the fuel consumption per unit time of the vehicle in the felling sub-stage, t' is the serial number of the vehicle used in the felling sub-stage, and t'i is the total number of vehicles used in the felling sub-stage;

[0065] The carbon footprint of human input in the harvesting sub-stage is calculated based on the following formula:

[0066]

[0067] Among them, E' 人力 is the carbon footprint of human input in the logging sub-stage, i is the activity number per unit area in the logging sub-stage, ri is the total number of activities per unit area in the logging sub-stage; EF' 人力 is the emission factor of labor input in the logging sub-stage, P' R is the number of people involved in the activity with serial number R per unit area in the harvesting sub-stage, T' R The number of working days for the activity with serial number R per unit area in the harvesting sub-stage.

[0068] The carbon emissions generated in the logging sub-stage are taken as the sum of the carbon footprint of energy input during the use of machinery in the logging sub-stage, the carbon footprint generated during the transportation process in the logging sub-stage, and the carbon footprint generated by manpower input in the logging sub-stage.

[0069] Preferably, the carbon emissions generated by the litter treatment sub-stage include carbon emissions generated by litter decomposition, and the carbon emissions generated by litter decomposition are calculated by the following formula:

[0070] PE'(t)=1-(e-k't)

[0071] cE′(t)=BC′×PE′(t)

[0072]

[0073] Among them, PE'(t) is the proportion of carbon in the biomass in the tth year, e is a natural constant, k' is the constant of the litter decomposition rate in the tth year, CE'(t) is the carbon content in the biomass collected in the tth year, BC' is the carbon content of the biomass collected in a certain year, CE(t) is the carbon emission generated by the decomposition of litter, t is the year number, and t' is the total number of years.

[0074] The beneficial effects of the present invention are:

[0075] 1. The production and management of eucalyptus is of great significance in the timber industry. Carbon footprint accounting for the production and management of eucalyptus can promote the sustainable development of the industry, optimize the efficiency of resource use, and enhance its competitiveness in the market.

[0076] 2. Combined with actual production conditions, improve the accuracy of accounting: The production and operation activities are divided into different stages, taking into account different logging methods and litter management. The stage division is detailed and in line with the actual work process, taking into account the accuracy of carbon footprint calculation and the convenience of implementation.

[0077] 3. Clearly focus on carbon emissions in the production and management process of eucalyptus, filling the technical gap: Clarify the carbon footprint accounting of the log production process, fill the gap in related technologies in this field, bring an innovative perspective to the measurement of carbon footprint, provide detailed and accurate data support, establish a new benchmark for the ecological management of eucalyptus forests, and promote the industry to develop in a sustainable direction

[0078] 5. The present invention pays attention to the carbon emissions in the forestry production and management process, provides new management ideas and practical guidance for forestry operators, and promotes the green transformation and upgrading of the forestry industry. Through the implementation of the present invention, carbon emissions in forestry activities can be more effectively monitored and managed, contributing to the realization of global carbon reduction goals.

[0079] 6. The model takes into account the differences in felling methods under different management models, covers the carbon emissions of eucalyptus wood under different management models, enhances the flexibility of the model, and is suitable for diversified production systems. It provides more comprehensive and accurate data for the carbon footprint accounting of eucalyptus plantations and provides a practical and reliable analysis tool for production systems under different environmental conditions.

[0080] 7. Analyze emission proportions and accurately quantify sources: Through detailed analysis of emission proportions, the emission sources in different activities or processes can be accurately divided and quantified, providing more insightful and practical carbon footprint information for industrial decision-making and promoting the sustainable development of forestry production.

[0081] 8. Reduce the error rate of the accounting process and improve data quality: Reduce potential errors and effectively reduce the error rate in low-carbon footprint accounting, thereby improving the overall data quality, providing a more reliable and accurate data basis for the carbon footprint accounting of eucalyptus plantation production and management, and providing a basis for emission reduction for the eucalyptus industry at the front end of the industrial chain.

[0082] 9. The present invention combines actual production and operation activities, takes into account all aspects of forestry production and operation, and significantly improves the accuracy of carbon footprint assessment. It covers the carbon emission characteristics of eucalyptus in different application scenarios, as well as seedling losses and resource inputs and emissions at various stages of production. Compared with the prior art, the present invention provides more detailed and accurate statistical data, thus achieving a qualitative leap in the accuracy of carbon footprint assessment.

[0083] 10. Consider emissions from different operating methods and provide targeted suggestions for reducing carbon footprint: Consider the specific carbon emission factors of different operating methods to provide more accurate calculation results and comprehensively capture the sources of carbon emissions in the production process through in-depth analysis of the different environmental adaptability of manual and mechanical operations, providing more operational and targeted suggestions for reducing carbon footprint.

[0084] 11. Focus on the introduction of new technologies and innovatively solve carbon footprint challenges: optimize the carbon emission accounting in the transportation stage (consider the transportation distances of different materials separately, and do not take the average value for calculation), etc., to make the overall accounting system more comprehensive. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] Figure 1 A flow chart of a method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management according to an embodiment of the present invention is shown.

[0086] Figure 2 A flow chart of carbon emission accounting for the litter treatment sub-stage according to an embodiment of the present invention is shown.

[0087] Figure 3 A system boundary diagram of the eucalyptus forest production and management sub-stages according to an embodiment of the present invention is shown.

[0088] Figure 4 It is a boundary diagram of the carbon emission accounting system of the production and management process of the short-cutting raw material forest under the condition of retaining litter in the present invention.

[0089] Figure 5 It is a boundary diagram of the carbon emission accounting system of the production and management process of the short-cutting raw material forest under the condition of burning litter in the present invention.

[0090] Figure 6 It is a boundary diagram of the carbon emission accounting system of the production and management process of the short-cutting raw material forest under the condition of removing litter in the present invention.

[0091] Figure 7 This is a boundary diagram of the carbon emission accounting system of the production and management process of large-diameter timber forests under the condition of retaining litter in the present invention.

[0092] Figure 8 It is a boundary diagram of the carbon emission accounting system of the production and management process of large-diameter timber forests under the condition of burning litter in the present invention.

[0093] Fig. 9 It is a boundary diagram of the carbon emission accounting system of the production and management process of large-diameter timber forests in the case of litter removal in the present invention. DETAILED DESCRIPTION

[0094] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the following embodiments and features in the embodiments can be combined with each other without conflict.

[0095] The specific implementation of the present invention is further described in detail below in conjunction with the drawings and examples.

[0096] As an important part of the terrestrial ecosystem, global forests play an important role in mitigating climate change. As an important artificial forest species, eucalyptus occupies a significant position in the world in terms of planting area and timber production. However, forestry production and management activities are also one of the main sources of greenhouse gas emissions. Therefore, accurately accounting for carbon emissions in the process of forestry production and management is crucial to achieving global carbon reduction targets.

[0097] Based on this, the embodiment of the present invention provides a method for calculating carbon emissions in the process of eucalyptus felling, residue treatment and production and management, which provides new business ideas and practical guidance for forestry operators and promotes the green transformation and upgrading of the forestry industry. Through the implementation of the present invention, carbon emissions in forestry activities can be more effectively monitored and managed, contributing to the realization of global carbon reduction goals.

[0098] The method of the present invention covers the entire life cycle from eucalyptus felling, transportation, wood processing to residue disposal. It calculates the carbon emissions generated in each link in detail and takes into account the impact of different business objectives and methods on carbon emissions.

[0099] The method includes the following key steps:

[0100] 1. Division of sub-stages within the life cycle: Determine the system boundaries and functional units of the carbon footprint.

[0101] 2. Determination of carbon emission inventory: Based on technical regulations and actual production information, an inventory analysis of inputs and outputs at each stage is conducted.

[0102] 3. Clarification of calculation methods and data requirements: Determine the calculation methods, allocation procedures, data requirements and emission factors for each stage.

[0103] 4. Uncertainty and sensitivity analysis: Analyze the emission proportions at different stages and evaluate the robustness of the method.

[0104] 5. Construction of carbon emission accounting model: Use emission factor method to construct a model to calculate the carbon footprint of the production and operation process.

[0105] Figure 1 The flowchart of the carbon emission accounting method for the eucalyptus felling, residue treatment and production and operation process is shown as follows: Figure 1 As shown, the method comprises the following steps:

[0106] S1. Divide the life cycle of eucalyptus logging, residue treatment and production management into sub-stages and determine the system boundaries and functional units of carbon footprint.

[0107] In this embodiment, the felling and transportation, felling residue treatment and production and management processes of eucalyptus plantations are classified, and the production and management modes of eucalyptus plantations are divided into short-felling raw material plantations and medium- and large-diameter timber forests. The treatment of fallen materials is divided into stacking, removal and burning, which specifically includes:

[0108] _a) Eucalyptus production and management refers to a series of activities related to the planting, management, felling and processing of eucalyptus, which increases the amount of wood resources and is mainly used in pulp, furniture making, construction, papermaking and other industries. According to different management purposes, eucalyptus plantations are divided into short-rotation industrial raw material forests and medium and large diameter timber forests;

[0109] _i) Eucalyptus short-rotation industrial raw material forest refers to an artificial forest that, under suitable site conditions, through breeding of improved varieties and intensive management, is targeted to provide wood raw materials for pulp, papermaking, wood-based panels, etc., and enables the forest growth to reach the required level in a short period of time. It has the characteristics of short wood cultivation cycle, high yield per unit area, and significant ecological benefits;

[0110] _ii) Eucalyptus medium and large-diameter timber forest refers to eucalyptus plantations whose main purpose is to cultivate larger diameter timber. They have a longer growth cycle and are mainly used as timber raw materials for sawn timber, furniture, construction, etc. They usually have the characteristics of long cultivation cycle, good timber quality and significant economic benefits.

[0111] (b) The litter treatment subsystem refers to the activities of managing and disposing of natural litter on the forest surface, such as leaves, twigs, bark, flowers and fruits, and other organic matter during forest management and administration;

[0112] _i) Retention: In some cases, litter is retained on the forest surface in order to increase soil organic matter, improve soil structure and enhance soil fertility.

[0113] _ii) Removal: Removal of all above-ground undecomposed organic matter, including trees, understory vegetation and ground cover.

[0114] _iii) Burning: Controlled burning of organic matter on the surface of forest land, such as leaves, dead branches, bark and other natural litter, within a forest or woodland.

[0115] In some embodiments, the sub-stages divided within the life cycle of eucalyptus logging, residue handling and production management include a production management sub-stage, a fallen material handling sub-stage, and a logging sub-stage.

[0116] Among them, the production and operation sub-stages include forest land preparation, land preparation, afforestation, weeding, fertilization, pest and disease control and other stages.

[0117] The forest preparation stage includes forest clearing. Forest clearing is generally carried out according to the actual situation of the afforestation land. There are comprehensive clearing, strip clearing or block clearing methods. Generally, the height of shrubs in the area is kept below 20cm after clearing. Some areas need to retain the original vegetation.

[0118] The land preparation stage refers to the process from forest land preparation to topsoil backfilling (clearing, land preparation, digging holes, applying base fertilizer, backfilling), which aims to provide a good growth environment for eucalyptus and regulate the afforestation environment.

[0119] Land preparation includes mechanical land preparation and manual land preparation. Mechanical land preparation refers to the use of mechanical land reclamation in forest land with a slope of less than 15°, which turns the soil in a certain direction on the afforestation land to form a long strip of tillage, improves the soil structure, increases the air permeability and permeability of the soil, and facilitates later operations; manual land preparation refers to the use of manual digging or land preparation with land reclamation in mountainous areas with a slope of more than 15°. Manual digging refers to the use of tools such as shovels and pickaxes to dig holes of a certain size and depth on the afforestation land for planting trees; land reclamation usually refers to turning the soil in a certain direction in the afforestation area to form a long strip of tillage, and the tillage belts generally have a certain interval.

[0120] Basal fertilizer refers to the fertilizer applied to the soil before or during planting. The purpose is to provide plants with a continuous and stable supply of nutrients to meet the nutritional needs of eucalyptus in the early growth stage. Fertilization and backfilling are generally carried out at the same time. When 1 / 3 of the soil is backfilled, fertilizer is added to the seed hole, and the topsoil is continued to be backfilled until the planting hole is filled.

[0121] Eucalyptus afforestation generally adopts two methods: seedling planting or stump regeneration. It refers to a series of activities of planting eucalyptus (Eucalyptus spp.) on specific land by artificial or mechanical methods; this process usually includes the steps of selecting suitable tree species, preparing land, planting, management and subsequent maintenance. Seedling planting refers to the artificial planting of cultivated seedlings in the soil according to the established density and layout on specific land to form an artificial forest that can meet human needs; stump regeneration usually refers to the renewal of the forest stand by using the natural germination ability of trees on the stumps of eucalyptus after felling, and through proper management, it grows into new plants; the tending management of eucalyptus plantations is to carry out regular weeding, fertilization, pest and disease control and other tending work during the growth of eucalyptus to promote the healthy growth of trees. Tending management also includes the tending of unforested land, such as loosening the soil, weed removal, topdressing and pest and disease control.

[0122] Young forest tending activities refer to the tending measures for trees in the early stages of tree growth. They include regular topdressing, weeding, pest control, and other tending measures. Targeted tending activities need to be taken according to different growth years.

[0123] The drop processing sub-phase includes three phases: retention, combustion and removal; among them:

[0124] The retention stage refers to retaining litter on the forest land without removing it. During the retention process, it is necessary to first set goals and strategies for retaining litter, and then regularly observe the impact of retained litter on the forest ecosystem and adjust management measures in a timely manner.

[0125] The burning stage refers to burning forest litter in situ or transporting it to a designated area for burning. During the burning process, it is first necessary to assess environmental risks and develop a burning plan; then, open a firebreak around the burning area, remove combustible materials, prevent the spread of fire or collect litter and transport it to a designated area. Finally, ignite the litter, and after the burning is over, check whether the area is at risk of re-ignition. After burning in the designated area, collect ashes for use as soil conditioner or fertilizer.

[0126] The removal stage refers to the collection and removal of litter from the forest area. It generally includes the following steps: collecting litter by manual or mechanical means, and then moving the collected litter to a collection point or directly loading it onto trucks and transporting it to the stacking area.

[0127] The felling sub-stage refers to the thinning or clear felling of trees after they have grown to a certain stage, based on management objectives and tree growth. Thinning can adjust the forest stand structure, while clear felling is to obtain mature timber.

[0128] In short-rotation industrial raw material forests, the clear-cut method is adopted to cut down mature forests that have met human needs. No thinning is carried out in short-rotation forests unless there are special circumstances. The affected trees need to be cut down in a timely manner only when pests and diseases or natural disasters occur;

[0129] For medium and large diameter timber plantations, thinning is required. When the initial planting density is reached, it is necessary to carry out tending thinning according to the actual growth of the forest stand. The principle of thinning is to remove the weak and retain the strong, retain the dominant trees with normal growth and development, and cut down the individuals with poor growth and development, bent trunks, bark injuries, and severe windbreaks.

[0130] Thinning generally starts 2 to 4 years after afforestation. When the stand density reaches above 0.8, the trees are strongly differentiated, and the suppressed trees account for 30% to 40% of the total number of trees, thinning begins. The thinning intensity does not exceed 30% of the number of trees, and the post-felling density is controlled at 0.6.

[0131] After the forest stand reaches the management requirements (generally 8 to 15 years), clear-cutting is carried out in small groups. In the blocks for sprouting and regeneration, the root height is controlled at 7 to 10 cm after manual felling; the root height of mechanical felling is controlled at 5 to 7 cm.

[0132] S2. According to the technical regulations and actual production information of eucalyptus felling, management and residue treatment, determine the carbon emission inventory of each sub-stage, analyze the carbon emission inventory of the eucalyptus production and management process within the life cycle, and determine the input and output inventory of each sub-stage.

[0133] Step S2 is the system boundary analysis step, which refers to the comprehensive assessment process of the product carbon footprint. This process involves comprehensive statistics, quantification, evaluation and comparison of all environmental impacts of the product throughout its entire life cycle from raw material acquisition to final disposal, including but not limited to the construction of a life cycle inventory, environmental impact assessment, sustainability analysis, supply chain management and dynamic assessment of the time dimension.

[0134] The product is eucalyptus logs produced from plantation forests.

[0135] The production system is a eucalyptus plantation.

[0136] The production cycle is the production cycle of eucalyptus plantations, which varies according to different management purposes.

[0137] Functional Unit (FU) is a one-hectare operating plot.

[0138] The scope of the System Boundary (SB) analysis includes the greenhouse gas inventory from litter handling to felling, including material and chemical inputs, electricity and fuel use, as well as inputs from plantations and material suppliers and product transportation consumption.

[0139] The functional unit (FU) of the system boundary is the eucalyptus planted on a 1-hectare plot, and the function of the studied system is to produce eucalyptus plantations for different uses. The activities / materials included in the boundary are related to the regeneration of eucalyptus in the forest.

[0140] S3. Determine the calculation methods, allocation procedures, data requirements and emission factors within each sub-stage.

[0141] It should be noted that the calculation methods in each sub-stage will be introduced in detail later. The production data involved come from technical regulations, data from the actual production process of forest farms, etc., and the emission factor data come from the carbon emission accounting standards of some countries and the China Carbon Emission Product Database.

[0142] S4. Use the emission factor method to construct the carbon emission accounting model for each sub-stage, and use the carbon emission accounting model for each sub-stage to obtain the carbon footprint of eucalyptus production and operation.

[0143] The carbon footprint of eucalyptus production and operation is the total carbon emissions generated during the eucalyptus production and operation stage. In this embodiment, the total carbon emissions generated during the eucalyptus production and operation stage are calculated using the following formula:

[0144] E t =E1+E2+E3

[0145] Among them, E t It represents the total carbon emissions generated in the eucalyptus wood production and management stage; E1 refers to the carbon emissions generated in the production and management sub-stage; E2 refers to the carbon emissions generated in the logging sub-stage; and E3 refers to the carbon emissions generated in the litter treatment sub-stage.

[0146] The inputs in the eucalyptus production and management process include energy inputs, pesticide inputs, and material inputs, which provide the total carbon footprint and footprint composition of the eucalyptus plantation. In this embodiment, the seedlings are qualified afforestation seconds from the nursery, and the specifications and quality of the seedling products meet the afforestation seedling selection standards. The activity unit can be restated as: it covers all links in the entire production process from raw material acquisition to the final completion of the product. Including but not limited to the following aspects: material procurement, land preparation, seedling input, planting, fertilization, weeding, pest control, harvesting, litter burning, decomposition, etc. Material input and distribution are all materials in the eucalyptus production and management activities, including the use and transportation of seedlings, fertilizers, pesticides, etc. and the configuration of production process activity trajectories, such as material distribution, etc.; greenhouse gas (GHG) emissions refer to the overall emissions of greenhouse gases generated by the consumption of natural resources and energy in production and operation activities, including every link from raw material collection to final disposal of products.

[0147] In some embodiments, carbon footprint accounting is performed for different inputs for each sub-stage, process and link, including on-site energy use, fertilizers, pesticides, reagents, consumables, labor, transportation and waste disposal, including dividing the eucalyptus production and management process into a forest clearing stage and a plantation tending stage, and dividing the carbon emissions involved in the eucalyptus production and management stage into energy, fertilizers, pesticides, chemicals, labor and transportation.

[0148] Collect input category data of each sub-stage and calculate carbon emissions of each stage to obtain the total carbon footprint of the entire eucalyptus forest production and management sub-stage.

[0149] Calculate the carbon emissions within one hectare of area, and expand the calculation to obtain the carbon emissions of the production and operation sub-stages.

[0150] In this embodiment, the carbon emissions generated by the production and operation sub-stage are calculated by the following method:

[0151] The carbon footprint of energy input for the use of machinery in the production and operation sub-stage is calculated based on the following formula:

[0152] E 能源1 =(M 柴油1 ×EF 柴油1 )

[0153]

[0154] V 机械m =T m1 ×U m1

[0155] Among them, E 能源1 M represents the carbon footprint of energy input used in the machinery in the production and operation sub-stage; 柴油1 The mass of diesel consumed by the machinery used in the production and operation sub-stage, EF 柴油1 is the emission factor for diesel, ρ 柴油1 is the average density of diesel used, m is the serial number of the machinery used in the production and operation sub-stage, mi is the total number of machinery used in the production and operation sub-stage, V 机械m is the diesel consumption of the mth machine in the production and operation sub-stage, T m1 The time that the mechanical work is spent on the production and operation sub-stage, in hours (h), U m1 The fuel consumption per unit time of the machinery in the production and operation sub-stage, in L / h;

[0156] The carbon footprint of fertilizer input is calculated based on the following formula:

[0157]

[0158] Among them, E 肥料 represents the carbon footprint of fertilizer input, f represents the sequence number of fertilizer, i represents the total number of fertilizer types, and F f represents the amount of the fth fertilizer applied to each eucalyptus tree, EF f represents the emission factor of the f-th fertilizer, T represents the frequency of application of the f-th fertilizer in the production and operation cycle, and N represents the number of eucalyptus trees per unit area;

[0159] The carbon footprint of pesticide input is calculated based on the following formula:

[0160]

[0161] Among them, E 农药 is the carbon footprint of pesticide input, p is the serial number of the pesticide, pi is the total number of pesticide types, P p is the amount of effective ingredient of the pth pesticide applied per unit area, S p is the total area sprayed with the pth pesticide, EF p is the emission factor of the active ingredient in the pth pesticide;

[0162] The carbon footprint generated by the transportation process in the production and operation sub-stage is calculated based on the following formula:

[0163]

[0164] in,

[0165] M 燃油1 =ρ 燃油1 ×D×C d

[0166] or

[0167] M 燃油1 =ρ 燃油1 ×T1×C t

[0168] in, is the carbon footprint generated during the transportation process, t1 is the vehicle serial number, ti is the total number of vehicles; M 燃油1 is the fuel quality, EF t1 is the emission factor of fuel used by vehicles, ρ 燃油1 is the average density of the fuel used, D is the transportation distance, C d is the fuel consumption per unit distance traveled by the vehicle, T1 is the driving time of the vehicle during transportation, C t is the fuel consumption of the truck per unit time;

[0169] The carbon footprint of human input in the production and operation sub-stage is calculated based on the following formula:

[0170]

[0171] Among them, EF 人力1 is the emission factor of human input in the production and operation sub-stage, r is the activity number per unit area in the production and operation sub-stage, ri is the total number of activities per unit area in the production and operation sub-stage; P r is the number of people involved in the activity with serial number r per unit area in the production and operation sub-stage, T r The number of working days for the activity with time serial number r in the production and operation sub-stage;

[0172] The carbon emissions generated in the production and operation sub-stage are taken as the sum of the carbon footprint of energy input used in machinery, the carbon footprint of fertilizer input, the carbon footprint of pesticide input, the carbon footprint generated in the transportation process of the production and operation sub-stage, and the carbon footprint generated in the human input of the production and operation sub-stage.

[0173] In some embodiments, due to the differences in inputs during clear felling and thinning, the carbon emissions generated will also be different. Therefore, the carbon emissions generated by the felling sub-stage are calculated using the following method:

[0174] The carbon footprint of energy input during the use of machinery in the harvesting sub-stage is calculated based on the following formula:

[0175]

[0176] V 机械m '=T m' ×U m'

[0177] in, M' represents the carbon footprint of energy input during the use of machinery in the harvesting sub-stage; 柴油 is the mass of diesel consumed by machinery in the harvesting sub-stage, EF' 柴油 is the emission factor for diesel fuel used in the harvesting sub-phase, ρ' 柴油 is the average density of diesel used in the harvesting sub-stage, m' is the serial number of the machine used in the harvesting sub-stage, m'i is the total number of machines used in the harvesting sub-stage, V 机械m' is the diesel consumption of the m'th machine in the harvesting sub-stage, T m' The time that the machine works in the felling sub-stage, in hours (h), U m' It is the fuel consumption per unit time of the machinery in the felling sub-stage, in L / h.

[0178] The carbon footprint of the transportation process in the harvesting sub-stage is calculated based on the following formula:

[0179]

[0180] in,

[0181] M′ 燃油 =ρ′ 燃油 ×D′×C′ d

[0182] or

[0183] M′ 燃油 =ρ′ 燃油 ×T′×C′ t

[0184] in, is the carbon footprint generated during the transportation process in the logging sub-stage, M′ 燃油 Fuel mass used for transportation during the harvesting sub-phase, EF t' is the emission factor for fuel used in the harvesting sub-phase, ρ' 燃油 is the average density of fuel used in the logging sub-stage, D' is the transportation distance in the logging sub-stage, C' d is the fuel consumption per unit distance of the vehicle in the logging sub-stage, T' is the driving time of the vehicle in the logging sub-stage, and C' t is the fuel consumption per unit time of the vehicle in the felling sub-stage, t' is the serial number of the vehicle used in the felling sub-stage, and t'i is the total number of vehicles used in the felling sub-stage.

[0185] The carbon footprint of human input in the harvesting sub-stage is calculated based on the following formula:

[0186]

[0187] Among them, E' 人力 is the carbon footprint of human input in the logging sub-stage, r is the activity number per unit area in the logging sub-stage, ri is the total number of activities per unit area in the logging sub-stage; EF' 人力 is the emission factor of labor input in the logging sub-stage, P' R is the number of people involved in the activity with serial number R per unit area in the harvesting sub-stage, T' R The number of working days for the activity with serial number R per unit area in the harvesting sub-stage.

[0188] The carbon emissions generated in the logging sub-stage are taken as the sum of the carbon footprint of energy input during the use of machinery in the logging sub-stage, the carbon footprint generated during the transportation process in the logging sub-stage, and the carbon footprint generated by manpower input in the logging sub-stage.

[0189] There are different ways to deal with eucalyptus residues, and the different treatment methods will lead to certain differences in carbon emissions. Litter refers to various organic materials that fall naturally from eucalyptus, including but not limited to fallen leaves, branches, bark, flowers, fruits and dead fine roots, and form a layer of cover on the surface of the forest. In artificial forests, the common ways to deal with litter are removal, stacking and burning. The current common treatment method is to stack it in place and wait for the litter to decompose naturally; in some areas affected by pests and diseases, the litter will be burned, and in some areas, the litter will be collected and burned. The emission calculation method for direct combustion of litter is: multiply the heat input joules of the litter by the fuel-specific CO2 emission factor (excluding non-CO2) emissions.

[0190] Therefore, in some embodiments, the carbon emissions generated in the litter treatment sub-stage are calculated by the following formula:

[0191] PE'(t)=1-(e-k't)

[0192] cE′(t)=BC′×PE′(t)

[0193]

[0194] Among them, PE′(t) is the proportion of carbon in the biomass in year t, e is a natural constant, k' is the constant of litter decomposition rate in year t, CE'(t) is the carbon content in the biomass collected in year t, BC' is the carbon content of the biomass collected in a certain year, CE(t) is the carbon emission generated by the litter treatment substage, t is the year number, and t' is the total number of years.

[0195] Calculation of total litter fall:

[0196] 1) Randomly set n 1x1m plots in the sample plot and collect litter on the forest surface. This should be done once at the end of each month.

[0197] 2) The collected litter is classified in the laboratory, and after removing the remaining debris, it is placed in a dryer for drying, and the dry weight is recorded as m1, m2, m3, ..., m n . And calculate the amount of litter per unit area of ​​1㎡ m;

[0198] 3) The amount of litterfall in time period i is

[0199] 4) Litter amount in the sample plot

[0200] In summary, the implementation of the present invention has the following significant advantages:

[0201] 1. It provides a new perspective and method, filling the gap in the field of carbon footprint accounting of eucalyptus plantations.

[0202] 2. Through the combination of detailed stage division and actual workflow, the accuracy of carbon footprint calculation and the convenience of operation are improved.

[0203] 3. It clarifies the carbon footprint accounting of the log production process and establishes new standards for the ecological management of eucalyptus forests.

[0204] 4. The differences in felling methods under different management models are taken into account, which enhances the flexibility and applicability of the model.

[0205] 5. Through detailed analysis of emission proportions, accurate quantification of carbon emission sources is provided, providing practical information for industrial decision-making.

[0206] 6. Reduce the error rate in the accounting process, improve data quality, and provide a reliable and accurate data basis for carbon footprint accounting.

[0207] The present invention not only provides a comprehensive and accurate method for calculating the carbon footprint of eucalyptus plantations, but also provides new management ideas and practical guidance for forestry operators, promoting the green transformation and upgrading of the forestry industry. Through the implementation of the present invention, carbon emissions in forestry activities can be more effectively monitored and managed, contributing to the realization of global carbon reduction goals.

[0208] The following will combine carbon emission calculation cases under eight different scenarios to further demonstrate the feasibility and advancement of the present invention.

[0209] Implementation Case 1: Carbon Emission Accounting of Litter Treatment Subsystem

[0210] like Figure 2As shown, it is a flow chart of carbon emission accounting of the litter treatment subsystem provided in an embodiment of the present invention. The carbon emission accounting of the litter treatment subsystem includes the following steps:

[0211] S110. Define the objectives, scope and functional units of the emission inventory:

[0212] (i) Objective: Calculate carbon emissions under different litter treatment scenarios.

[0213] (ii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0214] S120. Define the system boundary for the emissions inventory:

[0215] The system boundary of the litter management subsystem includes the calculation of litter amount, decomposition rate, carbon emission and the transportation involved in this process.

[0216] _(i) Select a research site and randomly set up n 1m×1m plots in the research site to collect litter at the end of each month. For example, 25 1m×1m litter collectors are randomly set up in the plot each year. These collectors are placed at different locations in the forest to obtain representative samples. At the end of each month, litter is collected and the collection devices are returned to their original locations;

[0217] (ii) The collected litter was divided into several categories in the laboratory, such as fallen leaves, fallen branches, bark, and fallen fruits. After removing other irrelevant debris, each type of litter was placed in a drying oven at 65°C until a constant dry weight was reached;

[0218] _(iii) The dried litter is weighed and its dry weight is recorded, such as m1, m2, ..., m25. Then the amount of litter per square meter per unit area in month i is

[0219] _(iv) Then the total amount of litter per unit area in month i is

[0220] _(v)The total amount of litter in the area is M a =S×M t , where S is the area of ​​the region.

[0221] S130. Calculate carbon emissions from litter decomposition.

[0222] Assume that the litter decomposition rate constant k' is 0.2 (per year), which represents the rate of litter decomposition under natural conditions. However, in actual situations, the decomposition rate varies from year to year, and generally the decomposition rate will accelerate in the later period. Use the following formula for calculation:

[0223] PE'(t)=1-(e-k't)

[0224] cE′(t)=BC′×PE′(t)

[0225]

[0226] Among them, PE'(t) refers to the proportion of carbon in biomass in a certain year, k' refers to the constant of litter decomposition rate in a certain year. cE'(t) refers to the carbon content of biomass collected in a certain year, BC' refers to the carbon content of biomass collected in a certain year. CE(t) refers to the carbon emission of biomass collected throughout the year.

[0227] S140, calculate the carbon emissions E generated by litter burning 燃 :

[0228] E 燃 =M t ×EF 凋

[0229] Among them, EF 凋 is the emission factor for litter burning.

[0230] The manpower and transportation input involved in the process, that is, the carbon footprint of manpower during litter burning, E 人力2 and transportation The carbon footprint is calculated using the following formula:

[0231]

[0232] Among them, EF 人力3 It refers to the emission factor of human input generated during litter burning, P r‘’ is the number of people involved in the r''th activity during litter burning per unit area, T r‘’ It is the number of days (the daily working hours are 8 hours) that the r'th number of people involved in the activity need to work during the litter burning process within a unit area.

[0233]

[0234] in,

[0235] M″ 燃油 =ρ″ 燃油 ×D″×C″ d

[0236] or

[0237] M″ 燃油 =ρ″ 燃油 ×T″×C″ t

[0238] Among them, M 燃油 Refers to the mass of fuel used in litter burning, EFt ” Refers to the emission factor of fuel used by trucks during litter burning, ρ” 燃油 It refers to the average density of fuel used in litter burning, D” refers to the transportation distance of litter burning, C″ d It refers to the fuel consumption per unit distance of the truck during litter burning, T' refers to the driving time of the truck during the transportation process of litter burning, and C' t ' refers to the fuel consumption per unit time of the truck during the litter burning process, t' is the serial number of the vehicle used in the litter burning process, and t'i is the total number of vehicles used in the litter burning process.

[0239] S150. Calculate the carbon emissions from the litter removal process. This treatment method mainly involves inputs of manpower and transportation, and is calculated using the following formula.

[0240]

[0241] Among them, E 人力3 It refers to the carbon footprint generated by human activities during litter removal. 人力3 refers to the emission factor of human input in the process of litter removal, r'''i refers to the total number of activities in the process of litter removal, P r‘'’ is the number of people involved in the r'''th activity in the process of litter removal per unit area, Tr ‘'’ It refers to the number of days (the daily working hours are 8 hours) that the r'th activity requires people to work in the process of litter removal per unit time.

[0242]

[0243] in,

[0244] M″′ 燃油 =ρ″′ 燃油 ×D″′×C″′ d

[0245] or

[0246] M″′ 燃油 =ρ″′ 燃油 ×T″′×C″′ t

[0247] in, Refers to the carbon footprint generated by litter removal during transportation, M″′ 燃油 Refers to the mass of fuel used in litter removal, EF t” Refers to the emission factor of fuel used by trucks during litter removal, ρ″′ 燃油It refers to the average density of fuel used in litter removal, D'' refers to the transportation distance in litter removal, C'' d It refers to the fuel consumption per unit distance of the truck during litter removal, T'' refers to the driving time of the truck during the transportation process of litter removal, and C' t ” refers to the fuel consumption per unit time of the truck during litter removal, t”’ is the serial number of the vehicle used in the litter removal process, and t”’i is the total number of vehicles used in the litter removal process.

[0248] Among them, the carbon emission coefficient data involved in implementation case 1 are shown in Table 1.

[0249] Table 1 Carbon emission coefficient data for implementation case 1

[0250]

[0251] Implementation case 2: Carbon emission accounting for the eucalyptus production and management sub-stage.

[0252] The carbon emission accounting of the eucalyptus production and management sub-stage includes the following steps:

[0253] S210. Define the objectives, scope and functional units of the emission inventory:

[0254] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production operations in South China and to estimate the carbon footprint of the entire production phase and of the different activities within the production phase.

[0255] (ii) Scope: The scope includes the life cycle stages from forest land clearing, young forest tending, plantation management, felling and transportation to the processing plant, i.e. the cradle to log production process and from forest farm to processing plant.

[0256] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0257] S220. Define the system boundary of the emissions inventory:

[0258] Figure 3 This is the system boundary diagram for the eucalyptus forest production and management sub-stage, such as Figure 3 As shown, the system boundary of the inventory includes the transportation of materials from producers to the forest farm, forest land clearing, planting, young forest care management, felling, and harvesting of all seedlings that meet production needs on one hectare of land.

[0259] S230. Quantify the resources involved in each activity:

[0260] The carbon footprint of energy input for the use of machinery in the production and operation sub-stage is calculated based on the following formula:

[0261] E能源1 =(M 柴油1 ×EF 柴油1 )

[0262]

[0263] V 机械m =T m1 ×u m1

[0264] Among them, E 能源1 M represents the carbon footprint of energy input used in the machinery in the production and operation sub-stage; 柴油1 The mass of diesel consumed by the machinery used in the production and operation sub-stage, EF 柴油1 is the emission factor for diesel, ρ 柴油1 is the average density of diesel used, m is the serial number of the machinery used in the production and operation sub-stage, mi is the total number of machinery used in the production and operation sub-stage, V 机械m is the diesel consumption of the mth machine in the production and operation sub-stage, T m1 The time that the mechanical work is spent on the production and operation sub-stage, in hours (h), U m1 The fuel consumption per unit time of the machinery in the production and operation sub-stage, in L / h;

[0265] The carbon footprint of fertilizer input is calculated based on the following formula:

[0266]

[0267] Among them, E 肥料 represents the carbon footprint of fertilizer input, f represents the sequence number of fertilizer, i represents the total number of fertilizer types, and F f represents the amount of the fth fertilizer applied to each eucalyptus tree, EF f represents the emission factor of the f-th fertilizer, T represents the frequency of application of the f-th fertilizer in the production and operation cycle, and N represents the number of eucalyptus trees per unit area;

[0268] The carbon footprint of pesticide input is calculated based on the following formula:

[0269]

[0270] Among them, E 农药 is the carbon footprint of pesticide input, p is the serial number of the pesticide, pi is the total number of pesticide types, P p is the amount of effective ingredient of the pth pesticide applied per unit area, S p is the total area sprayed with the pth pesticide, EF p is the emission factor of the active ingredient in the pth pesticide;

[0271] The carbon footprint generated by the transportation process in the production and operation sub-stage is calculated based on the following formula:

[0272]

[0273] in,

[0274] M 燃油1 =ρ 燃油1 ×D×C d

[0275] or

[0276] M 燃油1 =ρ 燃油1 ×T1×C t

[0277] in, is the carbon footprint generated during the transportation process, t1 is the vehicle serial number, ti is the total number of vehicles; M 燃油1 is the fuel quality, EF t1 is the emission factor of fuel used by vehicles, ρ 燃油1 is the average density of the fuel used, D is the transportation distance, C d is the fuel consumption per unit distance traveled by the vehicle, T1 is the driving time of the vehicle during transportation, C t is the fuel consumption of the truck per unit time;

[0278] The carbon footprint of human input in the production and operation sub-stage is calculated based on the following formula:

[0279]

[0280] Among them, EF 人力1 is the emission factor of human input in the production and operation sub-stage, r is the activity number per unit area in the production and operation sub-stage, ri is the total number of activities per unit area in the production and operation sub-stage; P r is the number of people involved in the activity with serial number r per unit area in the production and operation sub-stage, T r The number of working days for the activity with time serial number r in the production and operation sub-stage;

[0281] The carbon emissions generated in the production and operation sub-stage are taken as the sum of the carbon footprint of energy input used in machinery, the carbon footprint of fertilizer input, the carbon footprint of pesticide input, the carbon footprint generated in the transportation process of the production and operation sub-stage, and the carbon footprint generated in the human input of the production and operation sub-stage.

[0282] Among them, the carbon emission coefficient data involved in Implementation Case 2 is shown in Table 2.

[0283] Table 2 Carbon emission coefficient data for implementation case 2

[0284]

[0285] S240. Construct a life cycle emission inventory for the eucalyptus production and operation stages. Based on the quantified resources involved in each production stage, calculate the emissions during the life cycle of eucalyptus production and operation and summarize the emission inventory.

[0286] Implementation case 3: Carbon emissions from short-cut raw material forests with litter retention

[0287] Carbon emissions from short-cut raw material forests with litter retention specifically include the following steps:

[0288] S310. Define the objectives, scope and functional units of the emission inventory:

[0289] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production management in South China and to calculate carbon emissions from litter retention, production management sub-stage and harvesting sub-stage in large-diameter timber forests.

[0290] (ii) Scope: The scope includes litter retention, forest clearing, young forest tending, plantation management, felling and transportation to processing plants, i.e. the cradle to log production process and the forest farm to processing plant life cycle stages.

[0291] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0292] S320. Define the system boundary of the emissions inventory:

[0293] Figure 4 This is the boundary diagram of the carbon emission accounting system of the short-cutting raw material forest production and management process under the condition of retaining litter in the present invention. Figure 4 As shown in the figure, the system boundary of this inventory includes litter treatment, transportation of materials from producers to forest farms, forest clearing, planting, young forest tending management, and harvesting of seedlings to meet production needs on one hectare of land; short-rotation raw material forests are different from large-diameter eucalyptus timber forests in terms of growth cycle, forest cultivation methods, and nutritional management. Short-rotation raw material forests generally do not involve tending and thinning, and material inputs are also less.

[0294] S330. Quantify the inputs involved in each activity

[0295] (i) Energy input carbon footprint

[0296] E 能源 =(M 柴油 ×EF 柴油 )

[0297]

[0298] V 机械 =T m ×Um

[0299] (ii) Calculate the carbon footprint of fertilizer input based on the following formula:

[0300]

[0301] Among them, E 肥料 represents the carbon footprint of fertilizer input, F1 represents the amount of fertilizer applied to each eucalyptus tree, EF1 represents the emission factor of the fertilizer, T represents the frequency of application of the fertilizer during the production and operation cycle, and N represents the number of eucalyptus trees per unit area; the formula means that the sum of carbon emissions generated by the first to the i-th fertilizers in the production and operation process is the total carbon emissions generated by fertilizer input in the eucalyptus production and operation process.

[0302] (iii) Calculate the carbon footprint of pesticide input based on the following formula:

[0303]

[0304] Among them, P1 refers to the amount of active ingredient of a certain pesticide applied per unit area, S1 is the total area where the pesticide is sprayed, and EF1 is the emission factor of the active ingredient in the pesticide.

[0305] (iv) Calculate the carbon footprint of the transportation process based on the following formula:

[0306]

[0307] in,

[0308] M 燃油 =ρ 燃油 ×D×C d

[0309] or

[0310] M 燃油 =ρ 燃油 ×T×C t

[0311] Among them, M 燃油 Refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t Refers to the fuel consumption per unit time of the truck. It should be noted that in the actual transportation process, some models officially give the fuel consumption per 100 kilometers, while some models give the fuel consumption per hour. It is necessary to choose the appropriate method for calculation according to the actual situation.

[0312] (v) Calculate the carbon footprint of human input based on the following formula:

[0313]

[0314] Among them, EF 人力 It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that people involved in a certain activity need to work per unit time (the daily working hours are 8 hours). The emission factor of labor is 0.86 kgCO 2 / (man·sky).

[0315] (iv) Calculate the carbon footprint of litter input based on the following steps:

[0316] (a) In a one-hectare plot, n 1m×1m sample plots are randomly set up to collect litter at the end of each month. For example, 25 1m×1m litter collectors are randomly set up in the sample plot each year. These collectors are placed at different locations in the forest to obtain representative samples. At the end of each month, litter is collected and the collection devices are returned to their original locations;

[0317] (b) The collected litter was divided into several categories in the laboratory, such as fallen leaves, fallen branches, bark, and fallen fruits. After removing other irrelevant debris, each type of litter was placed in a drying oven at 65°C until a constant dry weight was reached; the dried litter was weighed and its dry weight was recorded, such as m1, m2, ..., m25.

[0318] The litter fall per square meter per unit area in the i-th month is

[0319] The total amount of litter per unit area in month i is The total amount of litter in the area is M a =S×M t , where S is the area of ​​the region.

[0320] (c) Assume that the litter decomposition rate constant k' is 0.2 (per year), which represents the rate of litter decomposition under natural conditions. However, in actual conditions, the decomposition rate varies from year to year, and generally the decomposition rate will accelerate in the later period. Calculate using the following formula

[0321] PE'(t)=1-(e-k't)

[0322] cE′(t)=BC′×PE′(t)

[0323]

[0324] S340. Construct a life cycle emission inventory for the eucalyptus production and operation stages, calculate the emissions during the eucalyptus production and operation life cycle based on the quantified resources involved in each production stage, and summarize the emission inventory.

[0325] Case study 4: Carbon emissions from short-cut raw material forests with litter burning

[0326] Carbon emissions from short-cut raw material forests under litter burning include the following steps:

[0327] S410. Define the objectives, scope and functional units of the emission inventory:

[0328] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production management in South China and to calculate carbon emissions from litter retention, production management sub-stage and harvesting sub-stage in large-diameter timber forests.

[0329] (ii) Scope: The scope includes litter retention, forest clearing, young forest tending, plantation management, felling and transportation to processing plants, i.e. the cradle to log production process and the forest farm to processing plant life cycle stages.

[0330] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0331] S420. Define the system boundary of the emissions inventory:

[0332] Figure 5 This is the boundary diagram of the carbon emission accounting system of the short-cutting raw material forest production and management process under the condition of burning litter in the present invention. Figure 5 As shown in the figure, the system boundary of this inventory includes litter treatment, transportation of materials from producers to forest farms, forest clearing, planting, young forest tending management, and harvesting of seedlings to meet production needs on one hectare of land. Compared with large-diameter eucalyptus timber forests, short-rotation raw material forests have differences in growth cycle, forest cultivation methods and nutritional management. Short-rotation raw material forests generally do not involve tending and thinning, and material inputs are also less.

[0333] S430. Quantify the inputs involved in each activity

[0334] (i) Energy input carbon footprint

[0335] E 能源 =(M 柴油 ×EF 柴油 )

[0336]

[0337] V 机械 =T m ×U m

[0338] It should be noted that the above calculation of energy input carbon footprint includes the calculation of energy input carbon footprint of each sub-stage.

[0339] (ii) Calculate the carbon footprint of fertilizer input based on the following formula:

[0340]

[0341] Among them, E 肥料 represents the carbon footprint of fertilizer input, F1 represents the amount of fertilizer applied to each eucalyptus tree, EF1 represents the emission factor of the fertilizer, T represents the frequency of application of the fertilizer during the production and operation cycle, and N represents the number of eucalyptus trees per unit area; the formula means that the sum of carbon emissions generated by the first to the i-th fertilizers in the production and operation process is the total carbon emissions generated by fertilizer input in the eucalyptus production and operation process.

[0342] (iii) Calculate the carbon footprint of pesticide input based on the following formula:

[0343]

[0344] Among them, P1 refers to the amount of active ingredient of a certain pesticide applied per unit area, S1 is the total area where the pesticide is sprayed, and EF1 is the emission factor of the active ingredient in the pesticide.

[0345] (iv) Calculate the carbon footprint of the transportation process based on the following formula:

[0346]

[0347] in,

[0348] M 燃油 =ρ 燃油 ×D×C d

[0349] or

[0350] M 燃油 =ρ 燃油 ×T×C t

[0351] Among them, M 燃油 Refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C tRefers to the fuel consumption per unit time of the truck. It should be noted that in the actual transportation process, some models officially give the fuel consumption per 100 kilometers, while some models give the fuel consumption per hour. It is necessary to choose the appropriate method for calculation according to the actual situation.

[0352] It should be noted that the above calculation of the carbon footprint of transport input includes the calculation of the carbon footprint of transport input in each sub-stage.

[0353] (v) Calculate the carbon footprint of human input based on the following formula:

[0354]

[0355] Among them, EF 人力 It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that people involved in a certain activity need to work per unit time (the daily working hours are 8 hours). The emission factor of labor is 0.86 kgCO 2 / (man·sky).

[0356] (iv) Calculate the carbon footprint of litter input based on the following steps:

[0357] (a) In a one-hectare plot, n 1m×1m sample plots are randomly set up to collect litter at the end of each month. For example, 25 1m×1m litter collectors are randomly set up in the sample plot each year. These collectors are placed at different locations in the forest to obtain representative samples. At the end of each month, litter is collected and the collection devices are returned to their original locations;

[0358] (b) The collected litter was divided into several categories in the laboratory, such as fallen leaves, fallen branches, bark, and fallen fruits. After removing other irrelevant debris, each type of litter was placed in a drying oven at 65°C until a constant dry weight was reached; the dried litter was weighed and its dry weight was recorded, such as m1, m2, ..., m25.

[0359] The litter fall per square meter per unit area in the i-th month is

[0360] The total amount of litter per unit area in month i is The total amount of litter in the area is M a =S×M t , where S is the area of ​​the region.

[0361] Emissions from litter burning are:

[0362] E 燃 =M t ×EF 凋

[0363] S440. Construct a carbon emission inventory for large-diameter timber forests treated with litter burning. Based on the quantified resources involved in each production stage, calculate the emissions during the life cycle of eucalyptus production and management and summarize the emission inventory.

[0364] Case study 5: Carbon emissions from short-cut raw material forests with litter removal

[0365] Carbon emissions from short-cut raw material forests with litter removal include the following steps:

[0366] S510. Define the objectives, scope and functional units of the emission inventory:

[0367] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production management in South China and to calculate carbon emissions from litter retention, production management sub-stage and harvesting sub-stage in large-diameter timber forests.

[0368] (ii) Scope: The scope includes litter retention, forest clearing, young forest tending, plantation management, felling and transportation to processing plants, i.e. the cradle to log production process and the forest farm to processing plant life cycle stages.

[0369] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0370] S520. Define the system boundary of the emissions inventory:

[0371] Figure 6 This is the boundary diagram of the carbon emission accounting system of the short-cutting raw material forest production and management process under the condition of removing litter in the present invention. Figure 6 As shown in the figure, the system boundary of this inventory includes litter treatment, transportation of materials from producers to forest farms, forest clearing, planting, young forest tending management, and harvesting of seedlings to meet production needs on one hectare of land. Compared with large-diameter eucalyptus timber forests, short-rotation raw material forests have differences in growth cycle, forest cultivation methods and nutritional management. Short-rotation raw material forests generally do not involve tending and thinning, and material inputs are also less.

[0372] S530. Quantify the inputs involved in each activity:

[0373] (i) Energy input carbon footprint

[0374] E 能源 =(M 柴油 ×EF 柴油 )

[0375]

[0376] V 机械 =T m ×U m

[0377] (ii) Calculate the carbon footprint of fertilizer input based on the following formula:

[0378]

[0379] Among them, E 肥料 represents the carbon footprint of fertilizer input, F1 represents the amount of fertilizer applied to each eucalyptus tree, EF1 represents the emission factor of the fertilizer, T represents the frequency of application of the fertilizer during the production and operation cycle, and N represents the number of eucalyptus trees per unit area; the formula means that the sum of carbon emissions generated by the first to the i-th fertilizers in the production and operation process is the total carbon emissions generated by fertilizer input in the eucalyptus production and operation process.

[0380] (iii) Calculate the carbon footprint of pesticide input based on the following formula:

[0381]

[0382] Among them, P1 refers to the amount of active ingredient of a certain pesticide applied per unit area, S1 is the total area where the pesticide is sprayed, and EF1 is the emission factor of the active ingredient in the pesticide.

[0383] (iv) Calculate the carbon footprint of the transportation process based on the following formula:

[0384]

[0385] in,

[0386] M 燃油 =ρ 燃油 ×D×C d

[0387] or

[0388] M 燃油 =ρ 燃油 ×T×C t

[0389] Among them, M fuel refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t Refers to the fuel consumption per unit time of the truck. It should be noted that in the actual transportation process, some models officially give the fuel consumption per 100 kilometers, while some models give the fuel consumption per hour. It is necessary to choose the appropriate method for calculation according to the actual situation.

[0390] (v) Calculate the carbon footprint of human input based on the following formula:

[0391]

[0392] Among them, EF 人力 It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that people involved in a certain activity need to work per unit time (the daily working hours are 8 hours). The emission factor of labor is 0.86 kgCO 2 / (man·sky).

[0393] (iv) Calculate the carbon footprint of litter input based on the following steps:

[0394] The carbon emissions from human input in collecting litter in one hectare of area are calculated using the following formula:

[0395]

[0396] Among them, EF 人力 It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that the number of people involved in a certain activity per unit time needs to work (the daily working hours are 8 hours). The emission factor of labor is 0.86kgCO2 / (person·day).

[0397] The litter is collected and transported to the destination. The carbon emissions during transportation are calculated using the following formula:

[0398]

[0399] in,

[0400] M 燃油 =ρ 燃油 ×D×C d

[0401] or

[0402] M 燃油 =ρ 燃油 ×T×C t

[0403] Among them, M fuel refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t It refers to the fuel consumption of a truck per unit time.

[0404] Case study 6: Carbon emissions from large-diameter timber forests with litter retention

[0405] Carbon emissions from large-diameter timber forests with litter retention include the following steps:

[0406] S610. Define the objectives, scope and functional units of the emission inventory:

[0407] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production management in South China and to calculate carbon emissions from litter retention, production management sub-stage and harvesting sub-stage in large-diameter timber forests.

[0408] (ii) Scope: The scope includes litter retention, forest clearing, young forest tending, plantation management, felling and transportation to processing plants, i.e. the cradle to log production process and the forest farm to processing plant life cycle stages.

[0409] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0410] S620. Define the system boundary of the emissions inventory:

[0411] Figure 7 This is the boundary diagram of the carbon emission accounting system of the large-diameter timber forest production and management process under the condition of retaining litter in the present invention. Figure 7 As shown in the table, the system boundary of this inventory includes litter treatment, transportation of materials from producers to forest farms, forest land clearing, planting, young forest cultivation and management, and harvesting of seedlings to meet production needs on one hectare of land; the system boundary is as follows Figure 7 Compared with short-cutting raw material forests, medium- and large-diameter eucalyptus forests have a longer management cycle and will undergo tending and thinning. In addition, more fertilizer is input.

[0412] S630, quantify the input involved in each activity,

[0413] (i) Energy input carbon footprint

[0414] E 能源 =(M 柴油 ×EF 柴油 )

[0415]

[0416] V 机械 =T m ×U m

[0417] (ii) Calculate the carbon footprint of fertilizer input based on the following formula:

[0418]

[0419] Among them, E 肥料represents the carbon footprint of fertilizer input, F1 represents the amount of fertilizer applied to each eucalyptus tree, EF1 represents the emission factor of the fertilizer, T represents the frequency of application of the fertilizer during the production and operation cycle, and N represents the number of eucalyptus trees per unit area; the formula means that the sum of carbon emissions generated by the first to the i-th fertilizers in the production and operation process is the total carbon emissions generated by fertilizer input in the eucalyptus production and operation process.

[0420] (iii) Calculate the carbon footprint of pesticide input based on the following formula:

[0421]

[0422] Among them, P1 refers to the amount of active ingredient of a certain pesticide applied per unit area, S1 is the total area where the pesticide is sprayed, and EF1 is the emission factor of the active ingredient in the pesticide.

[0423] (iv) Calculate the carbon footprint of the transportation process based on the following formula:

[0424]

[0425] in,

[0426] M 燃油 =ρ 燃油 ×D×C d

[0427] or

[0428] M 燃油 =ρ 燃油 ×T×C t

[0429] Among them, M fuel refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t Refers to the fuel consumption per unit time of the truck. It should be noted that in the actual transportation process, some models officially give the fuel consumption per 100 kilometers, while some models give the fuel consumption per hour. It is necessary to choose the appropriate method for calculation according to the actual situation.

[0430] (v) Calculate the carbon footprint of human input based on the following formula:

[0431]

[0432] Among them, EF 人力It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that the number of people involved in a certain activity per unit time needs to work (the daily working hours are 8 hours). The emission factor of labor is 0.86kgCO2 / (person·day).

[0433] (iv) Calculate the carbon footprint of litter input based on the following steps:

[0434] (a) In a one-hectare plot, n 1m×1m sample plots are randomly set up to collect litter at the end of each month. For example, 25 1m×1m litter collectors are randomly set up in the sample plot each year. These collectors are placed at different locations in the forest to obtain representative samples. At the end of each month, litter is collected and the collection devices are returned to their original locations;

[0435] (b) The collected litter was divided into several categories in the laboratory, such as fallen leaves, fallen branches, bark, and fallen fruits. After removing other irrelevant debris, each type of litter was placed in a drying oven at 65°C until a constant dry weight was reached; the dried litter was weighed and its dry weight was recorded, such as m1, m2, ..., m25.

[0436] The litter fall per square meter per unit area in the i-th month is

[0437] The total amount of litter per unit area in month i is The total amount of litter in the area is M a =S×M t , where S is the area of ​​the region.

[0438] (c) Assume that the litter decomposition rate constant k' is 0.2 (per year), which represents the rate of litter decomposition under natural conditions. However, in actual conditions, the decomposition rate varies from year to year, and generally the decomposition rate will accelerate in the later period. Calculate using the following formula

[0439] PE'(t)=1-(e-k't)

[0440] cE′(t)=BC′×PE′(t)

[0441]

[0442] S640. Construct a life cycle emission inventory for the eucalyptus production and operation stages. Based on the quantified resources involved in each production stage, calculate the emissions during the eucalyptus production and operation life cycle and summarize the emission inventory.

[0443] Case study 7: Carbon emissions from large-diameter timber forests treated with litter burning

[0444] Carbon emissions from large-diameter timber forests under litter burning treatment specifically include the following steps:

[0445] S710. Define the objectives, scope and functional units of the emissions inventory:

[0446] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production management in South China and to calculate carbon emissions from litter retention, production management sub-stage and harvesting sub-stage in large-diameter timber forests.

[0447] (ii) Scope: The scope includes litter retention, forest clearing, young forest tending, plantation management, felling and transportation to processing plants, i.e. the cradle to log production process and the forest farm to processing plant life cycle stages.

[0448] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0449] S720. Define the system boundary of the emissions inventory:

[0450] Figure 8 This is the boundary diagram of the carbon emission accounting system of the large-diameter timber forest production and management process under the condition of burning litter in the present invention. Figure 8 As shown, the system boundary of this inventory includes litter treatment, transportation of materials from producers to forest farms, forest clearing, planting, young forest nurturing management, and harvesting of seedlings to meet production needs on one hectare of land. Compared with short-felling raw material forests, medium and large-diameter eucalyptus timber forests have a longer management cycle and will undergo nurturing and thinning. In addition, more fertilizer input is required.

[0451] S730, Quantify the inputs involved in each activity

[0452] (i) Energy input carbon footprint

[0453] E 能源 =(M 柴油 ×EF 柴油 )

[0454]

[0455] V 机械 =T m ×U m

[0456] (ii) Calculate the carbon footprint of fertilizer input based on the following formula:

[0457]

[0458] Among them, E 肥料represents the carbon footprint of fertilizer input, F1 represents the amount of fertilizer applied to each eucalyptus tree, EF1 represents the emission factor of the fertilizer, T represents the frequency of application of the fertilizer during the production and operation cycle, and N represents the number of eucalyptus trees per unit area; the formula means that the sum of carbon emissions generated by the first to the i-th fertilizers in the production and operation process is the total carbon emissions generated by fertilizer input in the eucalyptus production and operation process.

[0459] (iii) Calculate the carbon footprint of pesticide input based on the following formula:

[0460]

[0461] Among them, P1 refers to the amount of active ingredient of a certain pesticide applied per unit area, S1 is the total area where the pesticide is sprayed, and EF1 is the emission factor of the active ingredient in the pesticide.

[0462] (iv) Calculate the carbon footprint of the transportation process based on the following formula:

[0463]

[0464] in,

[0465] M 燃油 =ρ 燃油 ×D×C d

[0466] or

[0467] M 燃油 =ρ 燃油 ×T×C t

[0468] Among them, M fuel refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t Refers to the fuel consumption per unit time of the truck. It should be noted that in the actual transportation process, some models officially give the fuel consumption per 100 kilometers, while some models give the fuel consumption per hour. It is necessary to choose the appropriate method for calculation according to the actual situation.

[0469] (v) Calculate the carbon footprint of human input based on the following formula:

[0470]

[0471] Among them, EF 人力It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that the number of people involved in a certain activity per unit time needs to work (the daily working hours are 8 hours). The emission factor of labor is 0.86kgCO2 / (person·day).

[0472] (iv) Calculate the carbon footprint of litter input based on the following steps:

[0473] (a) In a one-hectare plot, n 1m×1m sample plots are randomly set up to collect litter at the end of each month. For example, 25 1m×1m litter collectors are randomly set up in the sample plot each year. These collectors are placed at different locations in the forest to obtain representative samples. At the end of each month, litter is collected and the collection devices are returned to their original locations;

[0474] (b) The collected litter was divided into several categories in the laboratory, such as fallen leaves, fallen branches, bark, and fallen fruits. After removing other irrelevant debris, each type of litter was placed in a drying oven at 65°C until a constant dry weight was reached; the dried litter was weighed and its dry weight was recorded, such as m1, m2, ..., m25.

[0475] The litter fall per square meter per unit area in the i-th month is

[0476] The total amount of litter per unit area in month i is The total amount of litter in the area is M a =S×M t , where S is the area of ​​the region.

[0477] Emissions from litter burning are:

[0478] E 燃 =M t ×EF 凋

[0479] S740. Construct a carbon emission inventory for large-diameter timber forests treated with litter burning. Based on the quantified resources involved in each production stage, calculate the emissions during the life cycle of eucalyptus production and management and summarize the emission inventory.

[0480] Case Study 8: Carbon Emissions from Large-diameter Timber Forests after Litter Removal

[0481] Carbon emissions from large-diameter timber forests under litter removal treatment include the following steps:

[0482] S810. Define the objectives, scope and functional units of the emissions inventory:

[0483] (i) Objective: The objective of this inventory is to analyse the defined life cycle of eucalyptus production management in South China and to calculate carbon emissions from litter retention, production management sub-stage and harvesting sub-stage in large-diameter timber forests.

[0484] (ii) Scope: The scope includes litter retention, forest clearing, young forest tending, plantation management, felling and transportation to processing plants, i.e. the cradle to log production process and the forest farm to processing plant life cycle stages.

[0485] (iii) Functional unit: The functional unit is one hectare of eucalyptus forest production and management plot.

[0486] S820. Define the system boundary for the emissions inventory:

[0487] Fig. 9 This is the boundary diagram of the carbon emission accounting system of the large-diameter timber forest production and management process under the condition of removing litter in the present invention. Fig. 9 As shown, the system boundary of this inventory includes litter treatment, transportation of materials from producers to forest farms, forest clearing, planting, young forest tending management, harvesting of all seedlings to meet production needs on one hectare of land, and the differences in growth cycle, forest cultivation methods and nutritional management between large-diameter eucalyptus timber forests and short-rotation raw material forests.

[0488] S830. Quantify the inputs involved in each activity

[0489] (i) Energy input carbon footprint

[0490] E 能源 =(M 柴油 ×Ef 柴油 )

[0491]

[0492] V 机械 =T m ×U m

[0493] (ii) Calculate the carbon footprint of fertilizer input based on the following formula:

[0494]

[0495] Among them, E 肥料 represents the carbon footprint of fertilizer input, F1 represents the amount of fertilizer applied to each eucalyptus tree, EF1 represents the emission factor of the fertilizer, T represents the frequency of application of the fertilizer during the production and operation cycle, and N represents the number of eucalyptus trees per unit area; the formula means that the sum of carbon emissions generated by the first to the i-th fertilizers in the production and operation process is the total carbon emissions generated by fertilizer input in the eucalyptus production and operation process.

[0496] (iii) Calculate the carbon footprint of pesticide input based on the following formula:

[0497]

[0498] Among them, P1 refers to the amount of active ingredient of a certain pesticide applied per unit area, S1 is the total area where the pesticide is sprayed, and EF1 is the emission factor of the active ingredient in the pesticide.

[0499] (iv) Calculate the carbon footprint of the transportation process based on the following formula:

[0500]

[0501] in,

[0502] M 燃油 =ρ 燃油 ×d×C d

[0503] or

[0504] M 燃油 =ρ 燃油 ×T×C t

[0505] Among them, M fuel refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t Refers to the fuel consumption per unit time of the truck. It should be noted that in the actual transportation process, some models officially give the fuel consumption per 100 kilometers, while some models give the fuel consumption per hour. It is necessary to choose the appropriate method for calculation according to the actual situation.

[0506] (v) Calculate the carbon footprint of human input based on the following formula:

[0507]

[0508] Among them, EF 人力 It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that the number of people involved in a certain activity per unit time needs to work (the daily working hours are 8 hours). The emission factor of labor is 0.86kgCO2 / (person·day).

[0509] (iv) Calculate the carbon footprint of litter input based on the following steps:

[0510] The carbon emissions from human input in collecting litter in one hectare of area are calculated using the following formula:

[0511]

[0512] Among them, EF 人力 It refers to the emission factor of manpower input. P1 is the number of people involved in a certain activity per unit area. T1 refers to the number of days that the number of people involved in a certain activity per unit time needs to work (the daily working hours are 8 hours). The emission factor of labor is 0.86kgCO2 / (person·day).

[0513] The litter is collected and transported to the destination. The carbon emissions during transportation are calculated using the following formula:

[0514]

[0515] in,

[0516] M 燃油 =ρ 燃油 ×D×C d

[0517] or

[0518] M 燃油 =ρ 燃油 ×T×C t

[0519] Among them, M fuel refers to the fuel quality, EF t is the emission factor of fuel used by trucks, ρ 燃油 refers to the average density of the fuel used, D refers to the transportation distance, C d It refers to the fuel consumption of the truck per unit distance, T refers to the driving time of the truck during transportation, and C t It refers to the fuel consumption of a truck per unit time.

[0520] The above implementation modes are only used to illustrate the present invention, but not to limit the present invention. Ordinary technicians in the relevant technical field can make various changes and modifications without departing from the spirit and scope of the present invention. Therefore, all equivalent technical solutions also belong to the scope of the present invention. The patent protection scope of the present invention should be defined by the claims.

Claims

1. A method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management, characterized in that: include: Divide the sub-stages in the life cycle of eucalyptus harvesting, residue handling and production management and determine the system boundaries and functional units of carbon footprint; According to the technical regulations and actual production information of eucalyptus felling, management and residue treatment, determine the carbon emission inventory of each sub-stage, analyze the carbon emission inventory of the eucalyptus production and management process within the life cycle, and determine the input and output inventory of each sub-stage; Determine the calculation methods, allocation procedures, data requirements and emission factors within each sub-phase; The emission factor method is used to construct the carbon emission accounting model for each sub-stage, and the carbon footprint of eucalyptus production and operation is obtained using the carbon emission accounting model for each sub-stage.

2. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 1, characterized in that: The sub-stages divided within the life cycle of eucalyptus logging, residue treatment and production and management include the production and management sub-stage, the fallen material treatment sub-stage and the logging sub-stage.

3. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 2, characterized in that: The production and operation stages include forest land preparation stage, land preparation stage, afforestation stage, weeding stage, fertilization stage and pest and disease treatment stage; among which: The forest land preparation stage includes comprehensive clearing, strip clearing or block clearing; wherein the height of the regional shrubs after clearing is less than 20cm; The land preparation stage includes backfilling of topsoil, and the backfilling of topsoil includes cleaning, land preparation, hole digging, basal fertilizer application, and backfilling; wherein, the land preparation includes mechanical land preparation and manual land preparation, and the mechanical land preparation refers to the use of mechanical belt reclamation in forest land with a slope of less than 15° to cultivate the soil along a set direction on the afforestation land; the manual land preparation refers to the use of manual digging holes or belt reclamation for land preparation in mountainous areas with a slope of more than 15°, and manual hole digging refers to the use of tools to dig holes of a set size and depth on the afforestation land for planting trees; belt reclamation refers to the cultivation of soil along a set direction in the afforestation area to form a long strip of cultivation belt; basal fertilizer application refers to the fertilizer applied to the soil before or during plant planting; basal fertilizer application and backfilling are carried out simultaneously, and fertilizer is put into the hole when 1 / 3 of the soil is backfilled, and the topsoil is continued to be backfilled until the planting hole is filled; The afforestation stage includes two methods: seedling planting or stump cutting and renewal. Among them, seedling planting refers to planting cultivated seedlings into the soil in a predetermined density and layout on a designated land to form an artificial forest; stump cutting and renewal refers to renewing the forest stand on the stumps of felled eucalyptus trees by using the natural germination ability of trees to grow new plants.

4. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 2, characterized in that: The drop processing sub-stage includes a retention stage, a combustion stage and a removal stage; wherein: The retention stage refers to retaining litter on the forest land instead of removing it. During the retention process, the goal and strategy of retaining litter are set, and the impact of retained litter on the forest ecosystem is regularly observed to adjust management measures. The burning stage refers to burning the forest litter in situ or transporting it to a designated area for burning. During the burning process, environmental risks are assessed and a burning plan is formulated; a firebreak is opened around the designated area and combustibles are removed; the litter is ignited, and after the burning is completed, the designated area is checked for any risk of re-ignition. If there is no risk of re-ignition in the designated area, the ashes are collected and used as a soil conditioner or fertilizer; The removal stage refers to collecting and removing the litter from the forest area, including: collecting the litter and transporting the collected litter to the stacking area.

5. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 2, characterized in that: The felling sub-stage refers to the thinning or clear felling after the trees grow to the set stage, according to the management objectives and the growth of the trees; In short-rotation industrial raw material forests, the clear-cut method is adopted to cut down mature forests that meet the needs, and the damaged trees are only cut down when pests, diseases or natural disasters occur; In medium and large diameter timber plantations, the tending thinning method is adopted. When the initial planting density is reached, the tending thinning is carried out according to the actual growth of the forest stand. During the tending thinning process, the dominant trees with normal growth and development and suitable for cultivation are retained, and the individuals with poor growth and development, bent trunks, bark injuries, and severe windbreaks are cut off. The thinning method starts 2 to 4 years after afforestation, when the forest canopy density reaches above 0.8, the trees are strongly differentiated, and the suppressed trees account for 30% to 40% of the total number of trees, thinning begins; the thinning intensity does not exceed 30% of the number of trees, and the canopy density after felling is controlled at 0.6; The clear felling begins 8 to 15 years after afforestation. The height of the stumps after manual felling is controlled at 7 to 10 cm; the height of the stumps after mechanical felling is controlled at 5 to 7 cm.

6. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 2, characterized in that: The carbon emission accounting model of each sub-stage is constructed using the emission factor method, and the carbon footprint of eucalyptus production and operation is obtained using the carbon emission accounting model of each sub-stage, including: The total carbon emissions generated during the eucalyptus production and operation phase are calculated using the following formula: <h2 style=";text-align:left;direction:ltr">E<h2 style=";text-align:left;direction:ltr"> t <h2 style=";text-align:left;direction:ltr"> =E1+E2+E3 Among them, E t It represents the total carbon emissions generated in the eucalyptus wood production and management stage; E1 refers to the carbon emissions generated in the production and management sub-stage; E2 refers to the carbon emissions generated in the logging sub-stage; and E3 refers to the carbon emissions generated in the litter treatment sub-stage.

7. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 6, characterized in that: The carbon emissions generated by the production and operation sub-stage are calculated using the following method: The carbon footprint of energy input for the use of machinery in the production and operation sub-stage is calculated based on the following formula: HAVE BEEN 能源1 =(M 柴油1 ×EF 柴油1 ) V 机械m =T m1 ×U m1 Among them, E 能源1 M represents the carbon footprint of energy input used in the machinery in the production and operation sub-stage; 柴油1 The mass of diesel consumed by the machinery used in the production and operation sub-stage, EF 柴油1 is the emission factor for diesel, ρ 柴油1 is the average density of diesel used, m is the serial number of the machinery used in the production and operation sub-stage, mi is the total number of machinery used in the production and operation sub-stage, V 机械m is the diesel consumption of the mth machine in the production and operation sub-stage, T m1 is the total working time of mechanical work in the production and operation sub-stage, U m1 The fuel consumption per unit time of the machinery in the production and operation sub-stage; The carbon footprint of fertilizer input is calculated based on the following formula: Among them, E 肥料 represents the carbon footprint of fertilizer input, f represents the sequence number of fertilizer, i represents the total number of fertilizer types, and F f represents the amount of the fth fertilizer applied to each eucalyptus tree, EF f represents the emission factor of the f-th fertilizer, T represents the frequency of application of the f-th fertilizer in the production and operation cycle, and N represents the number of eucalyptus trees per unit area; The carbon footprint of pesticide input is calculated based on the following formula: Among them, E 农药 is the carbon footprint of pesticide input, p is the serial number of the pesticide, pi is the total number of pesticide types, P p is the amount of effective ingredient of the pth pesticide applied per unit area, S p is the total area sprayed with the pth pesticide, EF p is the emission factor of the active ingredient in the pth pesticide; The carbon footprint generated by the transportation process in the production and operation sub-stage is calculated based on the following formula: in, M 燃油1 =ρ 燃油1 ×D×C d or M 燃油1 =ρ 燃油1 ×T1×C t in, is the carbon footprint generated during the transportation process, t1 is the vehicle serial number, ti is the total number of vehicles; M 燃油1 is the fuel quality, EF t1 is the emission factor of fuel used by vehicles, ρ 燃油1 is the average density of the fuel used, D is the transportation distance, C d is the fuel consumption per unit distance traveled by the vehicle, T1 is the driving time of the vehicle during transportation, C t is the fuel consumption of the truck per unit time; The carbon footprint of human input in the production and operation sub-stage is calculated based on the following formula: Among them, EF 人力1 is the emission factor of human input in the production and operation sub-stage, r is the activity number per unit area in the production and operation sub-stage, ri is the total number of activities per unit area in the production and operation sub-stage; P r is the number of people involved in the activity with serial number r per unit area in the production and operation sub-stage, T r The number of working days for the activity with time serial number r in the production and operation sub-stage; The carbon emissions generated in the production and operation sub-stage are taken as the sum of the carbon footprint of energy input used in machinery, the carbon footprint of fertilizer input, the carbon footprint of pesticide input, the carbon footprint generated in the transportation process of the production and operation sub-stage, and the carbon footprint generated in the human input of the production and operation sub-stage.

8. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 6, characterized in that: The carbon emissions from the harvesting sub-phase are calculated as follows: The carbon footprint of energy input during the use of machinery in the harvesting sub-stage is calculated based on the following formula: V 机械m' =T m' ×U m' in, M' represents the carbon footprint of energy input during the use of machinery in the harvesting sub-stage; 柴油 is the mass of diesel consumed by machinery in the harvesting sub-stage, EF' 柴油 is the emission factor for diesel fuel used in the harvesting sub-phase, ρ' 柴油 is the average density of diesel used in the harvesting sub-stage, m' is the serial number of the machine used in the harvesting sub-stage, m'i is the total number of machines used in the harvesting sub-stage, V 机械m' is the diesel consumption of the m'th machine in the harvesting sub-stage, T m' The time used by the mechanical work in the felling sub-stage, in hours (h), U m' is the fuel consumption per unit time of the machinery in the harvesting sub-stage, in L / h; The carbon footprint of the transportation process in the harvesting sub-stage is calculated based on the following formula: in, M' 燃油 =p' 燃油 ×D'×C' d or M' 燃油 =p' 燃油 ×T'×C' t in, is the carbon footprint generated during the transportation process in the logging sub-stage, M' 燃油 Fuel mass used for transportation during the harvesting sub-phase, EF t' is the emission factor for fuel used in the harvesting sub-phase, ρ' 燃油 is the average density of fuel used in the logging sub-stage, D' is the transportation distance in the logging sub-stage, C' d is the fuel consumption per unit distance of the vehicle in the logging sub-stage, T' is the driving time of the vehicle in the logging sub-stage, and C' t is the fuel consumption per unit time of the vehicle in the felling sub-stage, t' is the serial number of the vehicle used in the felling sub-stage, and t'i is the total number of vehicles used in the felling sub-stage; The carbon footprint of human input in the harvesting sub-stage is calculated based on the following formula: Among them, E' 人力 is the carbon footprint of human input in the logging sub-stage, r is the activity number per unit area in the logging sub-stage, ri is the total number of activities per unit area in the logging sub-stage; EF' 人力 is the emission factor of labor input in the logging sub-stage, P' R is the number of people involved in the activity with serial number R per unit area in the harvesting sub-stage, T' R The number of working days for the activity with serial number R per unit area in the harvesting sub-stage; The carbon emissions generated in the logging sub-stage are taken as the sum of the carbon footprint of energy input during the use of machinery in the logging sub-stage, the carbon footprint generated during the transportation process in the logging sub-stage, and the carbon footprint generated by manpower input in the logging sub-stage.

9. The method for calculating carbon emissions during eucalyptus felling, residue treatment and production and management as claimed in claim 6, characterized in that: The carbon emissions generated by the litter treatment sub-stage include the carbon emissions generated by litter decomposition, and the carbon emissions generated by litter decomposition are calculated by the following formula: PE'(t)=1-(e-k't) cE'(t)=BC'×PE'(t) Among them, PE'(t) is the proportion of carbon in the biomass in the tth year, e is a natural constant, k' is the constant of the litter decomposition rate in the tth year, CE'(t) is the carbon content in the biomass collected in the tth year, BC' is the carbon content of the biomass collected in a certain year, CE(t) is the carbon emission generated by the decomposition of litter, t is the year number, and t' is the total number of years.

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