Method for establishing carbon sink index coefficient of water hyacinth wetland system

Abstract

The application discloses a method for establishing carbon sink index coefficient of water hyacinth wetland system, researches show that moderate water hyacinth has the function of purifying water body, however, water hyacinth flooding will lead to dissolved oxygen reduction, water quality deterioration and serious ecological imbalance, therefore, how to control the density of water hyacinth in the wetland so that the water purifying function can be maximally exerted and the negative influence on the aquatic ecosystem can be reduced is an urgent problem to be solved in water hyacinth wetland management, the application establishes the model relationship between the density of water hyacinth and the carbon sink index of the wetland, including the total organic carbon of water body, the organic carbon of sediment, the net photosynthesis of water hyacinth and the greenhouse gas emission of the wetland, the density of water hyacinth under the optimal carbon sink index of the wetland is controlled based on the method, the ecological benefit of the carbon sink of the water hyacinth wetland is effectively exerted, and the application has practical guiding significance for scientific management of the water hyacinth wetland.

Description

Technical Field

[0001] This invention relates to the field of plant monitoring technology, and more specifically, to a method for establishing carbon sequestration index coefficients in water hyacinth wetland systems. Background Technology

[0002] Water hyacinth is a floating aquatic herbaceous plant with a strong reproductive capacity. It can quickly invade surrounding water areas, forming large-scale monoculture communities, encroaching on reservoirs and lakes, and blocking waterways and irrigation canals. Extensive water surface coverage restricts light penetration, affecting the photosynthesis of underwater plants and thus impacting the balance of aquatic ecosystems. However, moderate amounts of water hyacinth can purify water. Studies indicate that the presence of water hyacinth can both increase and decrease greenhouse gas emissions. For example, water bodies covered by water hyacinth emit less CO2 than uncovered water bodies, suggesting that moderate amounts of water hyacinth may increase carbon sequestration. Therefore, how to weigh the advantages and disadvantages of water hyacinth in wetland systems is a current scientific challenge in the management of water hyacinth wetlands.

[0003] To date, there is a lack of an effective and intuitive method to express the carbon fixation of water hyacinth in water bodies. In order to further leverage the ecological benefits of water hyacinth, reduce its damage to wetlands, and fully utilize its functions in improving water quality and reducing greenhouse gas emissions, this invention establishes an index method based on the ecological benefits of water hyacinth carbon sequestration. By controlling the density of water hyacinth under the optimal carbon sequestration index of wetlands based on this method, the ecological benefits of water hyacinth wetland carbon sequestration can be effectively realized. Summary of the Invention

[0004] This invention provides a method for establishing a carbon sequestration index coefficient for a water hyacinth wetland system, thereby addressing the problem in the prior art of lacking an effective and intuitive way to express the carbon fixation of water hyacinth in water bodies.

[0005] To achieve the above objectives, the present invention provides the following technical solution:

[0006] A method for establishing a carbon sequestration index coefficient for a water hyacinth wetland system includes the following steps:

[0007] S1: Measure and calculate the density of water hyacinth in wetland waters, denoted as ρ;

[0008] S2: Monitor the total organic carbon index in the water body of the water hyacinth wetland system;

[0009] S3: Monitor greenhouse gas emission fluxes in water hyacinth wetland systems;

[0010] S4: Monitor the photosynthetic index of water hyacinth plants in the water hyacinth wetland system;

[0011] S5: Based on the above measurement results, establish a mathematical relationship model between water hyacinth density and wetland carbon sink indicators, including total organic carbon in water, organic carbon in sediments, net photosynthetic index of water hyacinth, and greenhouse gas emissions from wetlands.

[0012] S6: Based on the established mathematical relationship model, find and control the water hyacinth density under the optimal carbon sink index of the wetland system, guide the scientific management of water hyacinth wetlands, and effectively give full play to the ecological benefits of water hyacinth wetland carbon sink.

[0013] Preferably, step S2 specifically includes the following steps:

[0014] a) Use a water sampler to collect water samples from the water hyacinth-infested areas;

[0015] b) Collect water hyacinth wetland sediments using the Peterson mud sampler;

[0016] c) Take the sample back to the laboratory and determine it using a total organic carbon analyzer;

[0017] d) Establish a mathematical model relating the total organic carbon content of water bodies to the density of water hyacinth.

[0018] Preferably, step S3 specifically includes the following steps:

[0019] a) Select sampling points in the water hyacinth wetland and cover the sampling points with static floating boxes;

[0020] b) At 0 min and 30 min, the gas in the static floating box is drawn into the air bag through the three-way valve;

[0021] c) Establish a mathematical model relating greenhouse gas emission fluxes to water hyacinth density.

[0022] Preferably, step S4 specifically includes the following steps:

[0023] a) Select water hyacinth plants in the water hyacinth wetland and cover them with a black dark treatment box for dark treatment;

[0024] b) The leaves of water hyacinth were measured using a handheld fluorescent chlorophyll meter;

[0025] c) Convert field monitoring data into net photosynthetic index;

[0026] d) Establish a mathematical model relating net photosynthetic index to water hyacinth density.

[0027] Preferably, step S5 specifically includes the following steps:

[0028] Establish the relationship between water hyacinth density and various indicators, and model the mathematical relationship between the measured indicators and water hyacinth density as a quadratic parabola in one variable: Y = ax 2 +bx+c, that is:

[0029] The total organic carbon index of water bodies, Cd = aρ 2 +bρ+c;

[0030] The total organic carbon index of sediments, Cs = aρ 2 +bρ+c;

[0031] Greenhouse gas (CH4 or CO2) emission flux C p =aρ 2 +bρ+c;

[0032] Net photosynthetic index Cg=aρ 2 +bρ+c;

[0033] The conversion of water hyacinth density to the carbon sequestration index coefficient of the water hyacinth wetland system is as follows:

[0034] Water body total organic carbon index coefficient |k Cd |→ρ1,

[0035] Total organic carbon index coefficient of sediments |k Cs |→ρ2

[0036] Greenhouse gas (CH4 or CO2) index coefficient |k Cp |→ρ3,

[0037] Net photosynthetic index coefficient |k Cg |→ρ4;

[0038] Preferably, when |k Cd The closer the density is to 0, the lower the total organic carbon content in the water body is, and the water hyacinth density ρ1 at this time is close to the optimal density.

[0039] When |k Cs | The closer to 0, the higher the total organic carbon content of the sediment is, and the water hyacinth density ρ2 at this time is close to the optimal density.

[0040] When |k Cp The closer the density is to 0, the lower the greenhouse gas (CH4 or CO2) emissions are, and the corresponding water hyacinth density ρ3 is close to the optimal density.

[0041] When |k Cg The closer the value is to 0, the stronger the net photosynthesis of water hyacinth is at this point, and the corresponding water hyacinth density ρ4 is close to the optimal density.

[0042] Among the four values ​​ρ1, ρ2, ρ3, and ρ4, the minimum and maximum values ​​of ρ are selected. That is, by controlling the density of water hyacinth in wetlands under the optimal carbon sequestration index, it is kept within the range of [minimum ρ value, maximum ρ value], and this guides the scientific management of water hyacinth wetlands.

[0043] The principle and beneficial effects of this technical solution:

[0044] (1) This invention innovatively combines the density, photosynthesis, greenhouse gas flux and total organic carbon of the water hyacinth water area in the wetland system to form a complete cycle in order to evaluate the carbon sink function of water hyacinth in the wetland system. Using this method, we can understand the carbon sink process of water hyacinth in a keen and intuitive way, so as to further manage water hyacinth effectively, give full play to its ecological benefits, and reduce the time and economic cost of water hyacinth wetland management.

[0045] (2) The method for establishing carbon sink index coefficients of water hyacinth wetland system involved in this invention is simple to operate, takes little time, and is not limited by environment, and has advanced guiding role for water hyacinth wetland management. Attached Figure Description

[0046] Figure 1 A graph showing the relationship between water hyacinth density and water TOC;

[0047] Figure 2 A graph showing the relationship between water hyacinth density and sediment TOC;

[0048] Figure 3 The graph shows the relationship between the density of water hyacinth and methane.

[0049] Figure 4 A graph showing the relationship between the density of water hyacinth and carbon dioxide;

[0050] Figure 5 A graph showing the relationship between water hyacinth density and net photosynthesis; Detailed Implementation

[0051] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments:

[0052] Example:

[0053] Example 1: Determination and Analysis of Water Hyacinth Density and TOC

[0054] Water samples were collected from wetlands with different densities of water hyacinth using a water sampler and stored in water sample bottles. The samples were then brought back to the laboratory for analysis using a total organic carbon analyzer.

[0055] Sediment TOC Sampling and Determination: Water samples were collected at the sampling point using a Peterson sediment sampler and stored in sample bags. The samples were then brought back to the laboratory, dried, and impurities were removed. 50 ml of 0.5 mol·L⁻¹ sediment sample was added. -1 The K2SO4 solution was shaken thoroughly for 1 hour, then centrifuged at 1200 r / min for 10 minutes. The sample was then filtered using a vacuum pump and filtered through a 0.3 mm filter head. Finally, the total organic carbon was determined using a total organic carbon analyzer.

[0056] Total organic carbon (TOC) is an important indicator for evaluating the total amount of organic matter in water bodies. It expresses the amount of organic matter in water by the carbon content. The higher the TOC content in water bodies, the deeper the pollution. Therefore, we need to minimize the TOC content in water bodies and fix it in sediments.

[0057] according to Figure 1 By observing and comparing the slopes of the parabola at various points in the TOC vs. density graph recorded in the data, it can be concluded that when |k Cd |=0.12453 is closest to 0, at which point ρ1=20 plants / m 2 .

[0058] By observing and comparing the slopes of the parabola at various points in the TOC vs. density graph of sediments, we can deduce the result when |k Cs |=0.21917 is closest to 0, at which point ρ2=35 plants / m 2 .

[0059] Example 2: Water hyacinth density and greenhouse gas collection and measurement

[0060] At 0 min and 30 min respectively, the gas inside the floating static box was extracted into a gas bag and stored at the water hyacinth wetland sampling point using a three-way valve, and then analyzed using a gas chromatograph.

[0061] according to Figure 3 and Figure 4 By observing and comparing various points on the parabola in the methane-density relationship graph, it can be seen that when |k C1 |=0.03003 is closest to 0, at which point ρ3=8 plants / m 2 By observing and comparing various points on the parabola in the graph showing the relationship between carbon dioxide and density, it can be seen that when |k C2 |=0.03767 is closest to 0, at which point ρ4=23 plants / m 2 .

[0062] Example 3: Determination and Analysis of Water Hyacinth Density and Photosynthesis

[0063] The samples were darkened for 20 minutes and then measured in the field using a handheld fluorescent chlorophyll meter. The data were then brought back to the laboratory and analyzed using FlourPen and sigmaplot software. Figure 3 The ρ4 corresponding to the vertex of the parabola is 25 plants / m. 2 .

[0064] Based on the above, the optimal water hyacinth density range for wetland carbon sequestration can be determined. Taking the maximum and minimum values ​​of ρ1, ρ2, ρ3, ρ4, and ρ5, i.e., the range of [minimum ρ, maximum ρ], it is [8, 35] plants / m². 2The median was 23 plants / m². 2 Therefore, the optimal density of water hyacinth in a wetland is 23 plants / m². 2 .

[0065] Therefore, under the premise of comprehensively improving eutrophication or pollution in water hyacinth wetlands, the water hyacinth population should be maintained at 8-35 plants / m². 2 Only within a certain range can the ecological benefits of water hyacinth be maximized through carbon sequestration; when the density of water hyacinth exceeds 35 plants / m², it is considered to have limited ecological benefits. 2 In such cases, timely intervention should be implemented and the water hyacinth density should be controlled at 8 plants / m². 2 This allows it to simultaneously adsorb pollutants and purify water.

[0066] The specific usage and function of this embodiment are as follows:

[0067] S1: Measure and calculate the density of water hyacinth in wetland waters, denoted as ρ;

[0068] S2: Monitor the total organic carbon index in the water body of the water hyacinth wetland system;

[0069] S3: Monitor greenhouse gas emission fluxes in water hyacinth wetland systems;

[0070] S4: Monitor the photosynthetic index of water hyacinth plants in the water hyacinth wetland system;

[0071] S5: Based on the above measurement results, establish a mathematical relationship model between water hyacinth density and wetland carbon sink indicators, including total organic carbon in water, organic carbon in sediments, net photosynthetic index of water hyacinth, and greenhouse gas emissions from wetlands.

[0072] S6: Based on the established mathematical relationship model, find and control the water hyacinth density under the optimal carbon sink index of the wetland system, guide the scientific management of water hyacinth wetlands, and effectively give full play to the ecological benefits of water hyacinth wetland carbon sink.

[0073] S2 specifically includes the following steps:

[0074] a) Use a water sampler to collect water samples from the water hyacinth-infested areas;

[0075] b) Collect water hyacinth wetland sediments using the Peterson mud sampler;

[0076] c) Take the sample back to the laboratory and determine it using a total organic carbon analyzer;

[0077] d) Establish a mathematical model relating the total organic carbon content of water bodies to the density of water hyacinth.

[0078] S3 specifically includes the following steps:

[0079] a) Select sampling points in the water hyacinth wetland and cover the sampling points with static floating boxes;

[0080] b) At 0 min and 30 min, the gas in the static floating box is drawn into the air bag through the three-way valve;

[0081] c) Establish a mathematical model relating greenhouse gas emission fluxes to water hyacinth density.

[0082] S4 specifically includes the following steps:

[0083] a) Select water hyacinth plants in the water hyacinth wetland and cover them with a black dark treatment box for dark treatment;

[0084] b) The leaves of water hyacinth were measured using a handheld fluorescent chlorophyll meter;

[0085] c) Convert field monitoring data into net photosynthetic index;

[0086] d) Establish a mathematical model relating net photosynthetic index to water hyacinth density.

[0087] S5 specifically includes the following steps:

[0088] Establish the relationship between water hyacinth density and various indicators, and model the mathematical relationship between the measured indicators and water hyacinth density as a quadratic parabola in one variable: Y = ax 2 +bx+c, that is:

[0089] The total organic carbon index of water bodies, Cd = aρ 2 +bρ+c;

[0090] The total organic carbon index of sediments, Cs = aρ 2 +bρ+c;

[0091] Greenhouse gas (CH4 or CO2) emission flux C p =aρ 2 +bρ+c;

[0092] Net photosynthetic index Cg=aρ 2 +bρ+c;

[0093] The conversion of water hyacinth density to the carbon sequestration index coefficient of the water hyacinth wetland system is as follows:

[0094] Water body total organic carbon index coefficient |k Cd |→ρ1,

[0095] Total organic carbon index coefficient of sediments |k Cs |→ρ2

[0096] Greenhouse gas (CH4 or CO2) index coefficient |k Cp |→ρ3,

[0097] Net photosynthetic index coefficient |kCg |→ρ4;

[0098] When |k Cd The closer the density is to 0, the lower the total organic carbon content in the water body is, and the water hyacinth density ρ1 at this time is close to the optimal density.

[0099] When |k Cs | The closer to 0, the higher the total organic carbon content of the sediment is, and the water hyacinth density ρ2 at this time is close to the optimal density.

[0100] When |k Cp The closer the density is to 0, the lower the greenhouse gas (CH4 or CO2) emissions are, and the corresponding water hyacinth density ρ3 is close to the optimal density.

[0101] When |k Cg The closer the value is to 0, the stronger the net photosynthesis of water hyacinth is at this point, and the corresponding water hyacinth density ρ4 is close to the optimal density.

[0102] Among the four values ​​ρ1, ρ2, ρ3, and ρ4, the minimum and maximum values ​​of ρ are selected. That is, by controlling the density of water hyacinth in wetlands under the optimal carbon sequestration index, it is kept within the range of [minimum ρ value, maximum ρ value], and this guides the scientific management of water hyacinth wetlands.

[0103] The above descriptions are merely embodiments of the present invention, and common knowledge such as specific technical solutions and / or characteristics are not described in detail here. It should be noted that those skilled in the art can make various modifications and improvements without departing from the technical solutions of the present invention, and these should also be considered within the scope of protection of the present invention. These modifications and improvements will not affect the effectiveness of the implementation of the present invention or the practicality of the patent. The scope of protection claimed in this application should be determined by the content of its claims, and the specific embodiments described in the specification can be used to interpret the content of the claims.

Claims

1. A method for establishing a carbon sequestration index coefficient for a water hyacinth wetland system, characterized in that, Includes the following steps: S1: Measure and calculate the density of water hyacinth in wetland waters, denoted as ρ; S2: Monitor the total organic carbon index in the water body of the water hyacinth wetland system; S3: Monitor greenhouse gas emission fluxes in water hyacinth wetland systems; S4: Monitor the photosynthetic index of water hyacinth plants in the water hyacinth wetland system; S5: Based on the measurement results, establish a mathematical relationship model between water hyacinth density and wetland carbon sink indicators, including total organic carbon in water, organic carbon in sediments, net photosynthetic index of water hyacinth, and greenhouse gas emission indicators of wetlands. S6: Based on the established mathematical relationship model, find and control the density of water hyacinth under the optimal carbon sink index of the wetland system, guide the scientific management of water hyacinth wetlands, and effectively give full play to the ecological benefits of water hyacinth wetland carbon sink. S5 specifically includes the following steps: Establish the relationship between water hyacinth density and various indicators, and model the mathematical relationship between the measured indicators and water hyacinth density as a quadratic parabola in one variable: Y=ax 2 +bx+c, that is: The total organic carbon index of water bodies, Cd=a1ρ 2 +b1ρ+c1; Total organic carbon index of sediments Cs=a2ρ 2 +b2ρ+c2; Greenhouse gas emission flux C p =a3ρ 2 +b3ρ+c3; Net photosynthetic index Cg=a4ρ 2 +b4ρ+c4; The conversion of water hyacinth density to the carbon sequestration index coefficient of the water hyacinth wetland system is as follows: Water body total organic carbon index coefficient |k Cd |,|k Cd | represents the slope of the mathematical model of total organic carbon in water, and ρ1 represents the density of water hyacinth corresponding to each slope; Total organic carbon index coefficient of sediments |k Cs |,|k Cs | represents the slope of the mathematical model of total organic carbon in sediments, and ρ2 represents the density of water hyacinth corresponding to each slope; Greenhouse gas index coefficient |k Cp |,|k Cp | represents the slope of the mathematical relationship model of greenhouse gas indicators, and ρ3 represents the water hyacinth density corresponding to each slope; Net photosynthetic index coefficient |k Cg |,|k Cg | represents the slope of the mathematical model of the net photosynthetic index. ρ4 is the density of water hyacinth corresponding to each slope; When |k Cd The closer the density is to 0, the lower the total organic carbon content in the water body is, and the water hyacinth density ρ1 at this time is close to the optimal density. When |k Cs | The closer to 0, the higher the total organic carbon content of the sediment is, and the water hyacinth density ρ2 at this time is close to the optimal density. When |k Cp |The closer to 0, the lower the greenhouse gas emissions are, and the corresponding water hyacinth density ρ3 is close to the optimal density. When |k Cg The closer the density is to 0, the stronger the net photosynthesis of water hyacinth is at this time, and the corresponding density of water hyacinth ρ4 is close to the optimal density. Among the four values ​​ρ1, ρ2, ρ3, and ρ4, the minimum and maximum values ​​of ρ are selected. That is, by controlling the density of water hyacinth in wetlands under the optimal carbon sequestration index, it is kept within the range of [minimum ρ value, maximum ρ value], and this guides the scientific management of water hyacinth wetlands.

2. The method for establishing the carbon sequestration index coefficient of a water hyacinth wetland system according to claim 1, characterized in that: S2 specifically includes the following steps: a) Use a water sampler to collect water samples from the water hyacinth-infested area; b) Collect water hyacinth wetland sediments using the Peterson mud sampler; c) Take the sample back to the laboratory and determine it using a total organic carbon analyzer; d) Establish a mathematical model relating the total organic carbon content of water bodies to the density of water hyacinth.

3. The method for establishing the carbon sequestration index coefficient of a water hyacinth wetland system according to claim 1, characterized in that: S3 specifically includes the following steps: a) Select sampling points in the water hyacinth wetland and cover the sampling points with static floating boxes; b) At 0 min and 30 min, the gas in the static floating box is drawn into the air bag through the three-way valve; c) Establish a mathematical model relating greenhouse gas emission fluxes to water hyacinth density.

4. The method for establishing the carbon sequestration index coefficient of a water hyacinth wetland system according to claim 1, characterized in that: S4 specifically includes the following steps: a) Select water hyacinth plants in the water hyacinth wetland and cover them with a black dark treatment box for dark treatment; b) The leaves of water hyacinth were measured using a handheld fluorescent chlorophyll meter; c) Convert field monitoring data into net photosynthetic index; d) Establish a mathematical model relating net photosynthetic index to water hyacinth density.

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