Interplanting circulation system for improving nut forest soil through cassava straw

Abstract

The invention discloses an interplanting circulation system for improving nut forest soil by using cassava straws, and relates to the technical field of agricultural resource utilization and soil improvement, the system is constructed into six modules: a space configuration module realizes vertical layered planting of cassava and nuts; the time configuration module regulates and controls the straw decomposition period by spraying ethephon 10 days before cassava harvesting, and the straw decomposition period is synchronous with the nut fertilizer requirement period; the decomposition regulation and control module is coupled with a charcoal carrier by adopting a complex microbial inoculant, so that slow release of nitrogen and quick release of potassium are realized; the water and fertilizer cooperation module stores water through a furrow structure and conveys water through a straw water absorption layer in a dry season; the mechanical cooperation module is provided with a wheel track self-adaptive chassis and a dual-mode cutting head; the carbon sink metering module establishes a conversion rule of the straw returning amount and the carbon sink amount, organic matter of soil can be increased, the utilization rate of nitrogen can be increased, the use amount of chemical fertilizer is reduced, and therefore a soil nutrient management solution is provided for sustainable high yield of the nut forest.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of agricultural resource utilization and soil improvement, in particular to a kind of utilization cassava straw improves soil of nut forest interplanting circulation system. BACKGROUND

[0002] As an important economic crop, the annual yield of cassava straw is comparable to that of tuber. However, due to the lack of efficient utilization technology, most of the straw has been directly discarded or incinerated for a long time, which not only causes serious waste of biomass resources, but also easily leads to environmental problems such as air pollution. At the same time, nut forest (such as macadamia, walnut, etc.) as a perennial deep-rooted woody economic crop, generally faces the problems of low soil organic matter content, unbalanced nutrient supply and poor sustainability during the transition period from young tree stage to full fruiting stage, which limits the yield and quality of nuts. In the existing soil improvement measures, long-term reliance on chemical fertilizer application easily leads to soil degradation problems such as compaction and acidification; and the single crop straw returning mode often has defects such as mismatch between nutrient release period and key nutrient demand period of nut forest and poor improvement effect due to the lack of consideration of the matching of nutrient demand law of nut forest and straw decomposition characteristics, which is difficult to meet the needs of sustainable management of nut forest.

[0003] Currently, the research on resource utilization of cassava straw is mostly focused on herbaceous crop interplanting system. For example, patent CN105612998A discloses a method of interplanting cassava with peanuts and returning peanut straw to field, which increases soil organic matter by returning peanut straw to field. However, this technology is only suitable for short-term interplanting between shallow-rooted herbaceous crops, does not involve the interplanting adaptation problem of cassava and deep-rooted woody nut forest, and does not provide a solution to the slow decomposition problem caused by the toxicity of cyanogenic glycosides and high lignin content in cassava straw. The straw returning to field easily inhibits the growth of nut root system. Another existing technology designs a cutting device adapted to ridge cultivation, but the cutting head of the device can only handle a single type of straw, cannot meet the cross-scale operation needs of cassava narrow row spacing and nut forest wide row spacing, and does not integrate straw decomposition control mechanism, which leads to the difficulty in coordinating the nutrient release rate of straw and the key nutrient demand period such as nut flower differentiation, and cannot realize precise nutrient supply. The above existing technologies all have common defects such as limitation of interplanting object to herbaceous crops, mismatch between nutrient supply and nutrient demand period, and poor mechanization adaptability.

[0004] Based on the deficiencies of the existing technology, the core problem to be solved by the present application is: how to realize the dynamic and precise coordination of cassava interplanting system and deep-rooted nut forest in soil improvement and nutrient supply through precise spatio-temporal configuration optimization and straw decomposition process control, to eliminate the ecological niche competition between the two, and solve the problem of slow decomposition of cassava straw caused by its toxicity and high lignin content, to ensure the precise matching between the peak of straw nutrient release and the key nutrient demand period of nut forest. SUMMARY

[0005] The present application aims at solving the problems in the prior art and provides a kind of interplanting circulation system for improving soil of nut forest by cassava straw, which breaks through the technical barrier of existing herbaceous-woody crop interplanting synergy, realizes the precise synergy of cassava straw resource utilization and nut forest soil improvement, provides a soil nutrient management solution for sustainable high yield of nut forest.

[0006] The present application provides the following technical solutions to solve the above technical problems: on the one hand, an interplanting circulation system for improving soil of nut forest by cassava straw, comprising:

[0007] The space configuration module realizes vertical stratified distribution of cassava shallow root system and nut tree deep root system, and green manure crops cover the surface layer.

[0008] The time configuration module synchronizes the planting period of cassava and the end time of the dormancy period of nut trees, and controls the matching of the straw decomposition period with the high fertilizer demand period of nut trees.

[0009] The decomposition control module realizes slow release of nitrogen and rapid release of potassium by coupling composite microbial agent and biochar carrier.

[0010] The water and fertilizer coordination module uses ridge and furrow structure to accumulate water and direct water transfer in dry season through straw water absorption layer.

[0011] The mechanization coordination module adapts to interplanting operation through wheel distance self-adaptive chassis and double-mode cutting head.

[0012] In the space configuration module, nitrogen-fixing fast-growing green manure crops are planted between cassava rows, the decomposition control module includes cassava straw crushing device, composite microbial agent inoculation unit and microenvironment control unit, the water and fertilizer coordination module includes V-shaped diversion ridge, water storage ditch and capillary water transfer structure, and in the mechanization coordination module, the cutting head includes low-frequency high-torque mode and high-frequency crushing mode.

[0013] Further, the cassava is an early-mid-mature variety with a growth period of 180-210 days, and the planting row spacing is 0.8 meters, the nut tree adopts a planting specification of 5m x 6m, the root system distribution depth is 30-80 centimeters, the green manure crop root system distribution depth is 0-20 centimeters, the cassava straw is crushed to a particle size of 3-5 centimeters, the cassava is obtained by hybrid breeding to have a cyanogentic glycoside content of less than 50 milligrams per kilogram and a lignin content of less than 18%, the growth period regulation of the cassava includes delaying planting until the daily mean temperature is stably higher than 16℃, and completing harvesting between 180-210 days after planting, and the growth period regulation of the cassava also includes foliar spraying of ethephon with a concentration of 100 milligrams per liter 10 days before harvesting to reduce the straw carbon-nitrogen ratio to 35:1.

[0014] Further, the green manure crop is arrow pea and vetch, which is sown in the row after 30 days of cassava planting and is incorporated into the soil 30 days before the cassava is harvested, and the nitrogen fixation amount is 100 to 200 kilograms of nitrogen per hectare.

[0015] Further, the mass ratio of streptomyces to phanerochaete chrysosporium in the complex microbial agent is 1:1.

[0016] The inoculation method is to spray the microbial agent suspension through a microporous ceramic atomizing head on the straw layer, and the inoculation amount is 1x10^9 CFU per ton of straw.

[0017] The microenvironment control unit includes a humidity sensor, and the triggering condition is to start spraying when the soil humidity is lower than 60% and to stop spraying when the soil humidity is higher than 80%.

[0018] Further, the inclination angle of the V-shaped flow guide ridge is 45 degrees, the water storage ditch is paved with a cassava straw decomposition layer with a thickness of 20 centimeters, which is covered with a 5-centimeter clay isolation layer, the capillary water transport structure is composed of plant fiber bundles embedded in the straw decomposition layer, and the fiber bundles extend to a depth of 30 centimeters in the nut root distribution area.

[0019] Further, the hydraulic lifting system of the wheel track adaptive chassis responds to the GIS preset path signal.

[0020] In the young tree stage, the operation path is a bow-shaped traversal of the cassava and green manure planting area.

[0021] In the fruiting stage, the operation path is a straight line along the nut row, and the tree canopy vertical projection area is avoided within a range of 1 meter.

[0022] Further, it also includes an unmanned aerial vehicle monitoring unit, a multispectral sensor, and a Beidou positioning module, and the monitoring indicators are the SPAD value of the nut leaves and the soil electrical conductivity.

[0023] The logic for controlling the amount of straw returned to the field is: when the SPAD value is lower than 40, the amount of straw returned to the field is increased to 5 tons per hectare, and when the SPAD value is higher than 50, it is reduced to 2 tons per hectare, and the spreading accuracy is controlled by Beidou positioning.

[0024] Furthermore, it also includes blockchain carbon measurement units, soil organic carbon sensors and straw return meter;

[0025] The carbon footprint data is uploaded to the blockchain node, and the rule for generating carbon sink certificates is that each ton of cassava straw returned to the field corresponds to 0.25 tons of carbon dioxide equivalent;

[0026] The carbon sink trading interface is connected to the provincial carbon emission trading platform.

[0027] On the other hand, a method for intercropping and recycling nut forest soil using cassava straw is provided, wherein the specific steps of the method are as follows:

[0028] S100, time and space configuration: After the dormancy period of nut trees ends, when the average daily temperature reaches above 16°C, plant early- to mid-maturing varieties with a growing period of 180–210 days. Cassava rows should be spaced 0.8 meters apart, and nut trees should be planted in a 5m×6m planting format. Nitrogen-fixing fast-growing green manure crops should be sown synchronously between cassava rows.

[0029] S200, vertical hierarchical management:

[0030] Cassava is planted on V-shaped drainage ridges with a root distribution of 0-30 cm;

[0031] Green manure covers the surface layer, with a root distribution of 0-20 cm;

[0032] The root system of nut trees is distributed at a depth of 30-80 cm;

[0033] S300, straw treatment: spray 100 mg / L ethephon solution 10 days before cassava harvest, and cut the straw into 3-5 cm segments using high-frequency pulverization mode after harvest;

[0034] S400, decomposition control:

[0035] Spread the crushed straw at the bottom of the furrow with a thickness of 20 cm;

[0036] Inoculate 1×10 per ton of straw 9 CFU compound bacteria agent, and added special degradation agent to adapt to the decomposition characteristics of various types of straw, through the microporous ceramic atomization head to maintain soil moisture at 70%-80%;

[0037] Adding nut shell ash at 20% of straw weight promotes potassium release;

[0038] S500, water-fertilizer synergy: Turn over green manure 30 days before cassava harvest, and use the water stored in the ridges and the capillary action of the straw water absorption layer to transport water to the nut roots in the dry season;

[0039] S600, intelligent job:

[0040] Juvenile tree period: the wheel distance self-adaptive chassis synchronously manages cassava and green manure according to the arch-shaped path;

[0041] Fruiting period: along the straight line between the nut rows, avoid the tree crown projection area 1m range;

[0042] Based on unmanned aerial vehicle monitoring, the straw returning amount is dynamically adjusted according to the SPAD value of nuts, the returning amount is 5 tons per hectare when SPAD is less than 40, and the returning amount is 2 tons per hectare when SPAD is greater than 50, and the throwing precision is controlled;

[0043] S700, carbon sink certification: the straw returning amount and the soil carbon increment are measured, the blockchain carbon sink certificate corresponding to 0.25 tons of CO2 equivalent per ton of straw is generated and uploaded to the carbon trading platform.

[0044] Compared with the prior art, the interplanting circulation system for improving the soil of the nut forest by using cassava straw has the following beneficial effects:

[0045] 1. The vertical layered structure of cassava-nut-green manure is constructed, the problem of nutrient release cycle mispositioning caused by the fact that the existing interplanting mode does not consider the fertilizer requirement law of deep-rooted nut forest is solved, and the specific performance is that: early-mid mature varieties with a growth period of 180-210 days are used for cassava, and the cross-scale spatial configuration is formed with nut trees planted with a specification of 5m*6m, the shallow root layer and the deep root layer of the nut form a nutrient absorption gradient, 100mg / L ethephon is sprayed on the leaf surface 10 days before harvesting to regulate the straw decomposition process, the carbon-nitrogen ratio of cassava straw is reduced to 35:1, then the decomposition peak period is accurately overlapped with the nut flower bud differentiation period, and the wheel distance self-adaptive chassis and the double-mode cutting head are developed, the straw returning amount is dynamically regulated according to the SPAD value, so that the organic matter content of the soil of the nut forest is improved, the utilization rate of nitrogen is improved, and compared with the traditional mode, the application amount of chemical fertilizer can be reduced.

[0046] 2. The integration of the decomposition regulation module and the water and fertilizer coordination module can realize efficient conversion of straw resources and optimization of soil microenvironment, and the specific performance is that: the complex microbial agent of streptomyces and phanerochaete chrysosporium is sprayed on the straw layer through the microporous ceramic atomizing head, combined with the biochar carrier load, the nitrogen slow-release period can be prolonged, the potassium release rate can be improved, and through the cooperation of the ridge and furrow structure and the straw water absorption layer, the directional water delivery in the dry season can be realized, the soil water holding capacity can be improved, and the cellulose decomposition rate of the straw after ethylene treatment is improved, so that a virtuous cycle is formed.

[0047] Additional advantages, objects, and features of the application will be apparent to those skilled in the art upon examination of the following detailed description, it being understood that each BRIEF DESCRIPTION OF DRAWINGS

[0048] In order to more clearly illustrate the technical solutions of the embodiments of the present application or the prior art, the drawings needed to be used in the embodiments or the prior art description will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor on the basis of these drawings.

[0049] Figure 1 The operation flowchart of the present application is shown in the figure.

[0050] Figure 2 The module relationship diagram of the interplanting circulation system of the present application is shown in the figure.

[0051] Figure 3 The vertical stratification and decomposition control mechanism of the present application is shown in the figure. DETAILED DESCRIPTION

[0052] In order to further illustrate the technical means and effects adopted by the present application to achieve the predetermined invention purpose, the specific embodiments, structures, features and effects according to the present application will be described in detail below with reference to the drawings and preferred embodiments.

[0053] Embodiment one

[0054] As shown in Figure 2 and Figure 3 , the embodiment discloses a specific embodiment of an interplanting circulation system for improving soil of nut forest by cassava straw, which constructs a three-dimensional planting system of cassava, green manure and nut trees through organic combination of space configuration optimization, time period control, decomposition process management, water and fertilizer synergistic supply and mechanized intelligent operation. The system realizes efficient resource utilization of cassava straw, eliminates ecological niche competition between crops through vertical root stratification, promotes straw decomposition with the help of compound microbial agent and environmental regulation, and matches the fertilizer demand law of nut trees, at the same time, realizes directional supply of water through ridge and furrow structure and capillary water transport, cooperates with self-adaptive mechanized equipment and intelligent monitoring system, achieves the synergistic goals of soil improvement, accurate nutrient supply and carbon sink measurement, and provides a feasible technical scheme for sustainable high yield of nut forest.

[0055] The implementation process of the space configuration module is as follows.

[0056] The spatial configuration module is the basic architecture of the entire intercropping cycle system. Its core lies in achieving efficient use of land resources and avoiding resource competition between species through the vertical layered distribution of crop roots and optimization of planting layout. In this embodiment, the nut trees are selected from the local main perennial varieties, and the root distribution depth of the adult trees is mainly concentrated in 30-80 cm. This depth range is the core area for the nut trees to absorb nutrients and water. In order to form a vertical dislocation with the root system of the nut tree, the cassava is selected from the early and mid-maturing varieties with a planting period of 180-210 days. The root distribution depth is controlled at 0-30 cm, forming a clear vertical stratification with the root system of the nut tree, effectively avoiding direct competition between the two in soil nutrients and water absorption.

[0057] Cassava varieties were carefully selected, using hybrid breeding techniques to cultivate superior traits with cyanogenic glycoside content below 50 mg / kg and lignin content below 18%. Low cyanogenic glycoside content prevents toxicity to soil microorganisms and nut roots after straw return, while low lignin content paves the way for rapid straw decomposition, reducing resistance to material conversion during the decomposition process. Cassava rows are spaced 0.8 meters apart, ensuring the necessary ventilation and light for cassava growth while leaving ample space for intercropping green manure. Nut trees are planted in 5m x 6m strips, meeting the space required for nut tree crown growth while providing an appropriate planting strip width for intercropping cassava with green manure.

[0058] Green manure crops planted between the cassava rows include aralia and vetch, both nitrogen-fixing, fast-growing green manure varieties. Their root systems are concentrated at a depth of 0-20 cm, further filling the root niche in the surface layer, forming a three-layer vertical root structure: aralia (30-80 cm) - cassava (0-30 cm) - green manure (0-20 cm). This structure not only fully utilizes soil nutrients at different depths, but the shallow roots of the green manure also form a surface cover, reducing soil evaporation. At the same time, the nitrogen fixed during its growth replenishes the soil nitrogen pool. The planting method of green manure adopts a time sequence. It is sown between the rows 30 days after cassava planting. At this time, the cassava seedlings have begun to grow, and the sowing of green manure will not affect the early development of cassava; the green manure is turned into the soil 30 days before cassava harvest. At this time, the green manure is at its peak biomass and has sufficient nutrient content. After turning over, it can release nitrogen, phosphorus, potassium and other nutrients to the soil through decomposition. It has been calculated that the nitrogen fixation of green manure under this planting mode can reach 100 to 200 kilograms of nitrogen per hectare, which significantly improves the nitrogen supply capacity of the soil.

[0059] The implementation process of the time configuration module is as follows;

[0060] The time configuration module precisely controls the timing of crop planting, growth, harvesting, and straw decomposition to dynamically match the cassava growth cycle with the physiological needs of the nut trees. The core goal is to precisely coincide the peak nutrient release from straw decomposition with the peak fertilizer requirements of the nut trees. After their annual dormancy, nut trees enter a period of rapid growth, during which their nutrient demand increases dramatically. Therefore, the start of cassava planting is strictly guided by environmental conditions, delayed until the average daily temperature is consistently above 16°C. This temperature condition not only meets the requirements for cassava germination and growth, but also ensures that the cassava growth cycle starts in sync with the nutrient requirements of the nut trees.

[0061] Cassava varieties with an early to mid-maturing growth period of 180–210 days were selected to ensure that the cassava harvest and straw return to the fields were completed before the nut trees entered the next growth stage. To further optimize the straw's decomposition characteristics, 10 days before harvest, 100 mg / L of ethephon was sprayed onto the foliage. Ethephon promotes the physiological transformation of cassava straw, accelerating the decomposition of some organic matter within the straw and reducing the straw's carbon-nitrogen ratio to 35:1, the optimal ratio for straw decomposition. This prevents competition between microorganisms and crops for nitrogen caused by an excessively high carbon-nitrogen ratio, facilitating rapid straw decomposition and nutrient release.

[0062] Green manure management is also coordinated with the cycles of cassava and nut trees. Green manure is sown 30 days after cassava planting, allowing it to begin rapid growth in the middle of the cassava growth period and fully utilize the light and heat resources between the cassava rows. The green manure is turned over 30 days before cassava harvest, at which point its decomposition begins. The nutrients released by the green manure can then be combined with nutrients from the subsequent decomposition of cassava straw to ensure a continuous supply of soil nutrients from cassava harvest to the peak nutrient demand of the nut trees. This precise timing control achieves a closed-loop cassava growth-green manure decomposition-straw decomposition-nut nutrient demand cycle, maximizing nutrient utilization efficiency.

[0063] The implementation process of the decomposition control module is as follows;

[0064] The decomposition control module is the core link in achieving efficient nutrient conversion from cassava straw. Through inoculation with a composite microbial agent and microenvironmental control, it accelerates straw decomposition and regulates the rhythm of nutrient release, addressing the inefficient decomposition of cassava straw due to its high lignin content and potential toxicity. After harvesting, the cassava straw is first cut into 3-5 cm fragments using a high-frequency pulverization method. This particle size increases the contact area between the straw and microorganisms while avoiding the lack of aeration caused by smaller particles, providing an excellent material foundation for the decomposition process.

[0065] The composite microbial agent was selected through targeted screening and was formulated using a 1:1 mass ratio of Streptomyces and Phanerochaete chrysosporium. Streptomyces has a strong ability to decompose cellulose and hemicellulose in straw, while Phanerochaete chrysosporium effectively degrades lignin. The synergistic effect of the two significantly improves the overall decomposition efficiency of straw. The inoculation method uses a microporous ceramic atomizer to spray the suspension evenly onto the straw layer. The inoculation rate is controlled at 1×10 per ton of straw. 9 CFU, this atomized spraying method ensures that the bacterial agent can be evenly attached to the surface of the straw, thereby improving the colonization efficiency of microorganisms.

[0066] The microenvironment control unit plays a key role in the decomposition process. Equipped with a humidity sensor, it monitors the moisture levels of the soil and straw layer in real time. When soil moisture falls below 60%, the spray system automatically activates to replenish water. When the humidity rises above 80%, the spray system shuts down, maintaining the decomposition environment within the optimal humidity range of 70%-80%. This humidity promotes microbial activity and accelerates the decomposition and conversion of straw. Nutshell ash, rich in potassium and alkaline in nature, is added to the straw during decomposition, providing nutrients for microorganisms and regulating soil pH, promoting the rapid release of potassium from the straw and meeting the potassium needs of the nut trees.

[0067] Through the synergistic effect of compound microbial agents, appropriate particle size treatment, precise humidity control and the addition of nut shell ash, the decomposition cycle of cassava straw is significantly shortened, and the nutrient release pattern is highly matched with the fertilizer requirement rhythm of nut trees. Nitrogen is supplied in a slow release and potassium is supplied in a fast release, effectively improving the soil's nutrient supply capacity.

[0068] The implementation process of the water-fertilizer synergy module is as follows;

[0069] The water-fertilizer synergy module optimizes the ridge and ditch structure and water delivery system to achieve efficient water storage and targeted water delivery, addressing the dry season water supply issue for nut orchards. This module also synergizes nutrient release from straw decomposition to provide a nutrient-rich environment. The module's core structure comprises V-shaped diversion ridges, water storage ditches, and capillary water delivery structures, all integrated to form a complete water regulation system.

[0070] The inclination angle of the V-shaped diversion ridge is designed to be 45 degrees. This angle can maximize the collection of surface runoff and rainfall, while avoiding soil erosion caused by excessive angles. During rainfall or irrigation, water converges along the slope of the V-shaped ridge to the water storage ditch at the bottom, realizing centralized water collection. A 20-cm-thick layer of cassava straw decomposition is laid at the bottom of the water storage ditch. This layer serves as both a water storage carrier and a source of nutrient release. The porous structure formed by the straw during the decomposition process has a strong water retention capacity; a 5-cm loam isolation layer is covered above the decomposition layer. Its function is to prevent surface debris from entering the decomposition layer, and at the same time prevent harmful substances produced during the decomposition process from directly contacting the nut roots.

[0071] The capillary water transport structure is composed of plant fiber bundles embedded within the decomposing straw layer. These fiber bundles possess excellent water absorption and conductivity. One end of the fiber bundle is buried within the decomposing straw layer, while the other extends 30 centimeters into the nut root zone, the core absorption zone of the nut tree's root system. During the dry season, water accumulated in the reservoir ditch is transported to the nut root zone through the capillary action of the plant fiber bundles, providing a continuous water supply to the nut trees and avoiding the high evaporation losses and uneven water distribution associated with traditional irrigation methods.

[0072] The green manure that is turned over 30 days before cassava harvest will release a certain amount of water and nutrients during the decomposition process, which will synergize with the water transport of the water storage ditch, so that the soil can provide sufficient water while simultaneously supplying nutrients produced by the decomposition of green manure and straw, realizing the water-fertilizer synergistic effect of "water brings fertilizer, and fertilizer follows water", and significantly improving the water and fertilizer utilization efficiency of the nut forest at different growth stages.

[0073] The implementation process of the mechanized collaboration module is as follows;

[0074] The Mechanized Collaboration Module, through intelligent equipment adapted to the planting system, enables full mechanization of the entire process, from planting and management to harvesting and straw handling. This addresses the cross-scaling challenges of narrow cassava row spacing and wide nut plantation row spacing, improving system efficiency. The module's core equipment includes a wheelbase-adaptive chassis and a dual-mode cutting head, coupled with an intelligent path planning and monitoring system, enabling precise operation.

[0075] The adaptive wheelbase chassis is equipped with a hydraulic lift system that responds to GIS-preset path signals and automatically adjusts wheelbase and operating height based on the layout of the nut and cassava plantations at different growth stages. During the sapling stage, when the nut tree canopies are smaller, the operating path is designed to form an arched path through the cassava and green manure plantings. This path ensures full coverage of the planting area, enabling operations such as sowing, fertilizing, and weeding. During the peak fruiting stage, when the nut tree canopies have formed a large vertical projection, the operating path is adjusted to a straight line between the nut rows, strictly avoiding the vertical projection of the canopy by one meter to prevent damage to the fruit trees while ensuring efficient completion of operations such as straw crushing and pressing between the rows.

[0076] The cutting head is designed with two operating modes. The low-frequency, high-torque mode is suitable for processing coarse straw or stubble, achieving efficient cutting through high torque output. The high-frequency crushing mode is used for finely crushing cassava straw, cutting it into 3-5 cm fragments to meet the requirements of subsequent decomposition. These two modes can be switched in real time according to operational needs, adapting to different scenarios such as post-harvest cassava straw processing and green manure compaction.

[0077] The system also integrates a drone monitoring unit, a multispectral sensor, and a Beidou positioning module. The drone-mounted multispectral sensor regularly monitors the SPAD value of nut leaves and soil conductivity. The SPAD value reflects the chlorophyll content of the leaves, indirectly reflecting the nitrogen nutritional status of the nuts; soil conductivity reflects the nutrient and moisture status of the soil. The logic for regulating the amount of straw returned to the fields based on this monitoring data is as follows: when the SPAD value is below 40, indicating insufficient nitrogen supply for the nuts, the straw return rate is increased to 5 tons per hectare to improve nutritional status by increasing the nutrient supply from straw decomposition. When the SPAD value is above 50, the straw return rate is reduced to 2 tons per hectare to avoid nutrient overload. The Beidou positioning module is used to control the accuracy of straw spreading, ensuring a uniform spatial distribution of the return rate and improving the precision of nutrient management.

[0078] The implementation process of the carbon sequestration measurement module is as follows;

[0079] The carbon sequestration measurement module integrates soil carbon monitoring and blockchain technology to accurately measure the intercropping system's carbon footprint and generate carbon sequestration certificates, supporting the quantification of the system's ecological value. The module includes a blockchain carbon measurement unit, a soil organic carbon sensor, and a straw return meter, all of which work together to collect, calculate, and verify carbon sequestration data.

[0080] Soil organic carbon sensors, embedded at varying depths, monitor the dynamics of soil organic carbon content in real time, recording increases in soil carbon storage due to straw return and green manure compaction. Straw return metering devices, installed on mechanized equipment, accurately measure the weight of straw returned each time, serving as the basis for carbon sink calculations. The blockchain carbon metering unit receives data from the sensors and metering devices, calculates the carbon footprint according to pre-set rules, and generates an unalterable carbon sink data chain.

[0081] According to the system's established carbon sink certificate generation rules, each ton of cassava straw returned to the field is equivalent to a carbon sink of 0.25 tons of CO2 equivalent. This conversion relationship is determined by the efficiency of converting carbon into soil organic carbon during straw decomposition. The generated carbon sink data is uploaded to a distributed ledger via blockchain nodes, ensuring data transparency and credibility. Simultaneously, the system's carbon sink trading interface connects to the provincial carbon emissions trading platform, allowing the generated carbon sink certificates to enter the carbon emissions trading market. This achieves the economic transformation of ecological value, provides additional economic benefits to nut plantation growers, and incentivizes their continued adoption of this intercropping system.

[0082] In summary, this embodiment constructs a vertical root layering system of "nut trees-cassava-green manure" through the spatial configuration module, effectively eliminating niche competition among crops and improving land resource utilization; the time configuration module achieves precise matching of nutrient release and nut fertilizer requirements by regulating the cassava planting period, harvest period and straw decomposition period; the decomposition control module solves the problem of inefficient cassava straw decomposition with the help of composite bacterial agents and microenvironment control, and promotes slow release of nitrogen and rapid release of potassium; the water and fertilizer coordination module achieves efficient accumulation and directional transport of water through V-shaped diversion ridges, water storage ditches and capillary water transport structures, thereby improving water and fertilizer utilization efficiency; the mechanized coordination module achieves precision and efficiency of cross-scale operations through an adaptive chassis, dual-mode cutting head and intelligent monitoring system; the carbon sink measurement module quantifies the ecological value of the system and provides data support for carbon sink trading.

[0083] The entire intercropping cycle system achieves the multiple goals of resource utilization of cassava straw, soil improvement of nut forests, precise nutrient supply and quantification of ecological value. It effectively solves the problems of limited intercropping objects, misplaced nutrient supply, and poor mechanization adaptability in existing technologies, and provides a complete technical solution for the sustainable high yield of nut forests. It is suitable for promotion and application in nut forest planting areas with similar climate and soil conditions.

[0084] Example 2

[0085] like Figure 1 As shown, based on Examples 1 and 2, this example describes in detail the specific steps of an intercropping circulation system for improving nut forest soil using cassava straw. The specific steps are as follows:

[0086] S100, climate monitoring and start-up judgment: Continuously monitor the orchard environmental data. When it is confirmed that the dormancy period of the nut trees has ended and the average daily temperature has been stable above 16°C for 5 consecutive days, the system start-up command is triggered.

[0087] S110, Cassava and green manure sowing:

[0088] Using a wheelbase adaptive chassis, the sowing path is planned according to the preset nut tree planting specifications of 5m×6m x 0.8m (cassava row spacing).

[0089] Early-maturing cassava (an early-to-medium-maturing variety with a growth period of 180–210 days, cyanogenic glycosides <50 mg / kg, and lignin <18%) was planted between the nut rows using supporting sowing equipment at a row spacing of 0.8 m.

[0090] Between the cassava rows, nitrogen-fixing green manure crops (a mixture of arrow pea and potato) are sown simultaneously.

[0091] S200, stratified management during the growth period:

[0092] Cassava management: Cassava grows on the surface of V-shaped drainage ridges, and its roots are mainly distributed in the 0-30 cm soil layer.

[0093] Green manure management: Green manure crops cover the ground surface, and their roots are distributed in the 0-20 cm soil layer, playing a role in nitrogen fixation and moisture conservation.

[0094] Nut management: The deep root systems (30-80 cm) of nut trees do not compete with shallow crops for water and fertilizer.

[0095] S300, cassava pre-harvest treatment: 10 days before the planned harvest of cassava tubers, use drones or ground equipment to evenly spray 100 mg / L ethephon solution on the leaves of cassava plants.

[0096] S310, Cassava harvesting and straw processing:

[0097] Harvesting cassava tubers.

[0098] Switch the cutting head of the mechanized collaborative module to the "high-frequency crushing mode" to crush the cassava straw into 3-5 cm segments on site.

[0099] S400, straw return and microbial inoculation:

[0100] The crushed cassava straw is laid at the bottom of the water storage ditch with a thickness of about 20 cm.

[0101] A composite bacterial agent of Streptomyces and Phanerochaete chrysosporium with a mass ratio of 1:1 was prepared into a suspension and evenly sprayed onto the surface of the straw layer through a microporous ceramic atomizer at an inoculation rate of 1×10^9 CFU per ton of straw.

[0102] At the same time, a special composite degrader is added to adapt to the decomposition characteristics of various types of straw. The degrader is composed of lignin peroxidase (Lip), manganese peroxidase (MnP) and laccase (Laccase) in an activity unit ratio of 2:2:1. The added amount is 500 grams of enzyme powder per ton of straw (total enzyme activity ≥5000U / g). A small fertilizer spreader is used to evenly mix it with the straw fragments. It aims to specifically break the stubborn structure of high-lignin straw such as sorghum, corn, and sugarcane, and broaden the system's adaptability to different types of straw, such as for livestock feed.

[0103] At the same time, nut shell ash equivalent to 20% of the dry weight of the straw was evenly mixed.

[0104] S410, Decomposition Environment Maintenance: The microenvironment control unit is activated, and the humidity sensor continuously monitors the humidity of the straw layer. When the humidity drops below 60%, the spray system automatically activates to increase humidity; when the humidity rises above 80%, the system shuts down, maintaining the humidity within the optimal decomposition range of 70%-80%.

[0105] Under this humidity condition, the added composite bacterial agent and the special enzyme degradation agent work synergistically to significantly accelerate the decomposition process of straw, especially straw with a high degree of lignification.

[0106] S500, Green manure pressing: 30 days before cassava harvest, use machinery to press the green manure crops growing between the rows into the soil.

[0107] S510, Water and Fertilizer Cooperative Operation:

[0108] Water storage: V-shaped diversion ridges (45° inclination) divert rainfall or irrigation water to the storage ditch.

[0109] Water transport: In the dry season, the capillary water transport structure composed of the decomposed straw layer and the built-in plant fiber bundles in the water storage ditch transports water to the main root zone of the nuts at a depth of 30 cm.

[0110] S600, intelligent mechanical operation:

[0111] Young tree stage: The wheelbase adaptive chassis receives GIS path signals and traverses the entire working area along a "bow"-shaped path to complete management operations such as tillage and weeding.

[0112] During the peak fruit-bearing period, the chassis path is switched to driving in a straight line along the middle of the nut row, and it automatically avoids the range of 1 meter outside the vertical projection of the tree crown to carry out inter-row operations.

[0113] S610, Intelligent Control and Return of Farmland:

[0114] Drones equipped with multispectral sensors regularly patrol the fields to obtain SPAD values ​​of nut leaves and soil conductivity data.

[0115] If the SPAD value is <40, the system will determine that there is nitrogen deficiency and the amount of straw returned to the field will be increased to 5 tons / hectare in the next season.

[0116] If the SPAD value is >50, the system determines that there is sufficient nitrogen and the amount returned to the field in the next season is reduced to 2 tons / hectare.

[0117] When performing field return operations, the spreading device is controlled in combination with Beidou positioning information to achieve accurate spatial distribution of the amount returned to the field.

[0118] S700, Carbon sink data collection and certification:

[0119] The straw return meter records the dry matter mass returned to the field in real time.

[0120] Soil organic carbon sensors monitor changes in soil carbon storage.

[0121] The blockchain carbon metering unit receives data and generates an unalterable carbon sink certificate according to the rule of "1 ton of straw = 0.25 tons of CO2 equivalent".

[0122] Carbon offset certificates are automatically uploaded to the provincial carbon emission trading platform through the interface.

[0123] The above description is merely a preferred embodiment of the present invention and does not constitute any form of limitation to the present invention. Although the present invention has been disclosed as above in terms of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art can, without departing from the scope of the technical solution of the present invention, make some changes or modifications to equivalent embodiments using the technical contents disclosed above. However, any brief modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An intercropping circulation system for improving nut forest soil using cassava straw, characterized in that: include: Spatial configuration module to achieve vertical layered distribution of shallow cassava roots and deep nut tree roots, with green manure crops covering the surface layer; The time configuration module synchronizes the cassava planting period with the end of the nut tree dormancy period, and adjusts the straw decomposition period to match the peak fertilizer demand period of the nut trees; The decomposition control module achieves slow release of nitrogen and rapid release of potassium by coupling a composite bacterial agent with a biochar carrier; The water-fertilizer coordination module uses the ridge structure to store water and delivers water in a targeted manner through the straw water absorption layer during the dry season; Mechanized collaborative module, adapting to various operations through wheelbase adaptive chassis and dual-mode cutting head; Among them: in the spatial configuration module, nitrogen-fixing fast-growing green manure crops are planted between cassava rows, the decomposition regulation module includes a cassava straw crushing device, a composite bacterial agent inoculation unit and a microenvironment control unit, the water and fertilizer coordination module includes a V-shaped diversion ridge, a water storage ditch and a capillary water supply structure, and in the mechanized coordination module, the cutting head includes a low-frequency high-torque mode and a high-frequency crushing mode.

2. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: The cassava is an early to mid-maturing variety with a growing period of 180-210 days, and is planted with a row spacing of 0.8 meters. The nut trees are planted in a 5m×6m planting specification, with a root distribution depth of 30-80 centimeters. The root distribution depth of the green manure crop is 0-20 centimeters. The crushed cassava straw has a particle size of 3-5 centimeters. The cassava has been obtained through hybrid breeding to have a cyanogenic glycoside content of less than 50 mg / kg and a lignin content of less than 18%. The growth period regulation of the cassava includes delaying planting until the daily average temperature is stably above 16°C, and completing harvesting between 180-210 days after planting. The growth period regulation of the cassava also includes foliar spraying of ethephon at a concentration of 100 mg / L, 10 days before harvest, so that the carbon-nitrogen ratio of the straw is reduced to 35:

1.

3. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: The green manure crops are arrow pea and potato, which are planted in the rows 30 days after cassava is planted and pressed into the soil 30 days before cassava is harvested. The nitrogen fixation capacity is 100 to 200 kilograms per hectare.

4. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: The mass ratio of Streptomyces to Phanerochaete chrysosporium in the composite bacterial agent is 1:1; The inoculation method is: spray the bacterial suspension onto the straw layer through a microporous ceramic atomizer, with an inoculation rate of 1×10^9 CFU per ton of straw; The microenvironment control unit includes a humidity sensor, and the trigger condition is to start spraying when the soil humidity is lower than 60% and shut down when it is higher than 80%.

5. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: The inclination angle of the V-shaped diversion ridge is 45 degrees. A 20-cm-thick cassava straw decomposition layer is laid at the bottom of the water storage ditch, which is covered with a 5-cm loam isolation layer. The capillary water transport structure is composed of plant fiber bundles embedded in the straw decomposition layer, and the fiber bundles extend to a depth of 30 cm in the nut root distribution area.

6. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: The hydraulic lifting system of the wheelbase adaptive chassis responds to the GIS preset path signal; During the sapling stage, the operation path is in a bow shape, traversing the cassava and green manure planting areas; During the peak fruit-bearing period, the operation path is to move in a straight line between the nut rows, and avoid the vertical projection area of ​​the tree crown within 1 meter.

7. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: It also includes a drone monitoring unit, a multispectral sensor, and a Beidou positioning module. The monitoring indicators are the SPAD value of nut leaves and soil conductivity; The logic for controlling the amount of straw returned to the field is: when the SPAD value is lower than 40, the amount of straw returned to the field is increased to 5 tons per hectare, and when the SPAD value is higher than 50, it is reduced to 2 tons per hectare, and the spreading accuracy is controlled by Beidou positioning.

8. The intercropping circulation system for improving nut forest soil by using cassava straw according to claim 1, characterized in that: It also includes a blockchain carbon metering unit, a soil organic carbon sensor, and a straw return meter; The carbon footprint data is uploaded to the blockchain node, and the rule for generating carbon sink certificates is that each ton of cassava straw returned to the field corresponds to 0.25 tons of carbon dioxide equivalent; The carbon sink trading interface is connected to the provincial carbon emission trading platform.

9. A method for intercropping and recycling of nut forest soil using cassava straw, applicable to the intercropping and recycling system for improving nut forest soil using cassava straw according to any one of claims 1 to 8, characterized in that: The specific steps of this method are: S100, time and space configuration: After the dormancy period of nut trees ends, when the average daily temperature reaches above 16°C, plant early- to mid-maturing varieties with a growing period of 180–210 days. Cassava rows should be spaced 0.8 meters apart, and nut trees should be planted in a 5m×6m planting format. Nitrogen-fixing fast-growing green manure crops should be sown synchronously between cassava rows. S200, vertical hierarchical management: Cassava is planted on V-shaped drainage ridges with a root distribution of 0-30 cm; Green manure covers the surface layer, with a root distribution of 0-20 cm; The root system of nut trees is distributed at a depth of 30-80 cm; S300, straw treatment: spray 100 mg / L ethephon solution 10 days before cassava harvest, and cut the straw into 3-5 cm segments using high-frequency pulverization mode after harvest; S400, decomposition control: Spread the crushed straw at the bottom of the furrow with a thickness of 20 cm; Inoculate 1×10 per ton of straw 9 CFU compound bacteria agent, and added special degradation agent to adapt to the decomposition characteristics of various types of straw, through the microporous ceramic atomization head to maintain soil moisture at 70%-80%; Adding nut shell ash at 20% of straw weight promotes potassium release; S500, water-fertilizer synergy: Turn over green manure 30 days before cassava harvest, and use the water stored in the ridges and the capillary action of the straw water absorption layer to transport water to the nut roots in the dry season; S600, Intelligent Operation: Young tree stage: The wheelbase adaptive chassis manages cassava and green manure synchronously along a bow-shaped path; Peak fruiting period: Walk in a straight line between the nut rows, avoiding the projection area of ​​the tree crown within 1 meter; The amount of straw returned to the field is dynamically adjusted based on the SPAD value of nuts monitored by drones. When SPAD is less than 40, the amount returned is 5 tons / hectare, and when SPAD is greater than 50, the amount returned is 2 tons / hectare, to control the spreading accuracy. S700, Carbon sink certification: Measure the amount of straw returned to the field and the increase in soil carbon, generate blockchain carbon sink certificates based on 0.25 tons of CO2 equivalent per ton of straw, and upload them to the carbon trading platform.

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