Method for promoting rapid increase of soil carbon sequestration of southern Xinjiang farmland

Abstract

A method for promoting rapid improvement of soil carbon sequestration of southern Xinjiang farmland comprises the steps that 1, in winter of the first year, a land is selected and spread with a bio-organic fertilizer, and then rotary tillage is conducted; 2, in spring of the second year, dividing areas, and planting crops and green manure respectively; 3, in autumn of the second year, crop straw and green manure are smashed, EM bacterium diluent is sprayed, organic fertilizer is formed through fermentation and spread, and rotary tillage is carried out; 4, in spring of the third year, all crops are planted, and all straws are separated from the field after the crops are harvested. According to the method, firstly, the organic carbon content and the soil carbon sink of farmland soil can be rapidly increased through the strategy that the biological organic fertilizer and the straw are alternately returned to the field, the soil structure is improved, and formation of soil aggregates is promoted; secondly, bio-organic fertilizer is used, the chemical fertilizer input is reduced, the crop yield is increased, and economic benefits are improved; finally, the bio-organic fertilizer is formed through straw fermentation, and environmental pollution caused by straw incineration, stacking and the like is reduced.

Description

Technical Field

[0001] The present invention relates to the field of farmland soil improvement, and more specifically, to a method for promoting rapid improvement of farmland soil carbon sink in southern Xinjiang. Background Art

[0002] The soil carbon pool is the largest carbon pool in the earth's terrestrial ecosystem, with a carbon storage of about three times that of the atmospheric carbon pool. The soil carbon pool and its dynamic changes have an important impact on global climate change. Since the "4 / 1000" international initiative launched by France at the United Nations Climate Change Conference in Paris in 2015, the role of soil carbon sink has attracted much attention. Therefore, developing effective soil carbon sequestration strategies and improving soil carbon sinks are of immeasurable value for achieving global climate goals and ensuring the ecological security of the earth.

[0003] The total cultivated land area in southern Xinjiang (the southern part of Xinjiang) is about 34.7 million mu. With abundant light and heat resources, it is one of the important grain, cotton and oil producing areas in China. Affected by factors such as climate, soil parent material, and farming methods, the organic matter content of farmland soil in southern Xinjiang is generally low, with more than 50% of the cultivated layer soil organic matter content below 10g·C·kg -1 According to the national soil nutrient classification standard, it is at the fifth level, which is a low level and has great potential for increasing soil carbon sinks. The application of organic materials is one of the effective ways to increase soil carbon sinks. On the one hand, the application of organic materials directly introduces rich organic matter into the soil, directly increasing soil carbon sinks; on the other hand, the application of organic materials can promote microbial activity, promote the formation of aggregate structure, improve the effectiveness of soil nutrients, promote the growth and development of crops, and then increase the distribution of crop photosynthetic products to the underground, indirectly increasing soil carbon sinks. Among many organic materials, the role of biological organic fertilizers is more prominent. The microorganisms in biological organic fertilizers can secrete a variety of enzymes, such as cellulase and protease, to accelerate the decomposition of organic matter such as animal and plant residues in the soil, promote the formation of stable organic-inorganic complexes, and facilitate the long-term accumulation of soil organic matter and the improvement of soil carbon sinks. In addition, crop straw is also one of the high-quality organic materials for improving soil carbon sinks. Using crop straw to return to the field to increase soil organic carbon can not only increase soil carbon sinks, but also eliminate pollution caused by burning straw. However, crop straw contains high levels of difficult-to-decompose substances such as cellulose, hemicellulose, and lignin. In addition, the dry and cold climate conditions in southern Xinjiang in winter and spring easily cause the accumulation of straw in the soil, which is not conducive to the formation of soil carbon sinks.

[0004] Therefore, the problems existing in the prior art need to be further improved and developed. Summary of the invention

[0005] (I) Purpose of the invention: In order to solve the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a method for promoting the rapid improvement of soil carbon sinks in farmland in southern Xinjiang, by adopting a planting model that combines crops with green manure and integrating the strategy of on-site mixed fermentation and return of crop straw and green manure to the field, so as to rapidly improve the soil carbon sinks in farmland in southern Xinjiang.

[0006] (II) Technical solution: In order to solve the above technical problems, this technical solution provides a method to promote the rapid improvement of soil carbon sinks in southern Xinjiang farmland, specifically including: Step 1, first winter: select a site and spread bio-organic fertilizer, then rotary tillage; Step 2: In the spring of the second year: divide the area and plant crops and green manure separately; Step 3, in the autumn of the second year: crush the crop straw and green manure, spray the diluted EM bacteria solution, ferment it to form organic fertilizer and spread it, and then till the soil; Step 4: Spring of the third year: Plant all crops and remove all straw from the fields after the crops are harvested.

[0007] Preferably, step 1 is to select a soil with an organic carbon content less than or equal to 20 g·C·kg -1 , spread bio-organic fertilizer on farmland with salt content less than or equal to 0.4%; after spreading, rotary till the land where bio-organic fertilizer is spread.

[0008] Preferably, the spreading area of ​​the bio-organic fertilizer is 400-600 kg / mu; the bio-organic fertilizer contains Trichoderma, Bacillus subtilis and EM compound bacteria; and the rotary tillage depth is 20-25 cm.

[0009] Preferably, the step 2 is to prepare the land and divide it into planting areas and intercropping areas, wherein the planting areas are used for planting crops and the intercropping areas are used for planting green manure.

[0010] Preferably, the division into planting areas and intercropping areas means that an intercropping area is provided between two planting areas to form a repeating unit and circulate; the planting area width is 1.5 to 2 m, and the intercropping area width is 0.4 to 0.6 m.

[0011] Preferably, after the crops are harvested, the crop straw and green manure left in the field are crushed, the crushed crop straw and green manure are fully mixed, and after spraying EM bacterial solution, they are stacked on the spot, covered with film, and fermented to form organic fertilizer; after the fermentation is completed, the organic fertilizer is evenly spread on the field and rotary tilled.

[0012] Preferably, the length of the crop straw and green manure after crushing is 2 to 3 cm; and the EM bacterial solution is a 100 to 300-fold diluted EM bacterial solution.

[0013] Preferably, the crop straw sprayed with EM bacterial liquid and green manure are piled on site into a conical pile with a diameter of 0.8 to 1 m and a height of 0.6 to 0.8 m, covered and sealed with a PO film, and fermented at a temperature of 25 to 35° C. for 30 to 40 days to form organic fertilizer.

[0014] Preferably, the organic fertilizer is also evenly spread at 400-600 kg / mu; the rotary tillage depth is 20-25 cm.

[0015] Preferably, steps 1 to 4 are repeated to increase the organic carbon content and soil carbon sink of farmland soil.

[0016] (III) Beneficial effects: The present invention provides a method for rapidly improving soil carbon sinks in farmland in southern Xinjiang. Firstly, through the strategy of returning bio-organic fertilizers and straw alternately to the fields, the organic carbon content and soil carbon sink of farmland soil can be rapidly increased, the soil structure can be improved, and the formation of soil aggregates can be promoted; secondly, bio-organic fertilizers can be used to reduce the input of chemical fertilizers, increase crop yields, and enhance economic benefits; finally, bio-organic fertilizers can be formed through straw fermentation to reduce environmental pollution caused by straw burning and stacking. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 This is a flow chart of the steps of a method for promoting rapid improvement of soil carbon sequestration in farmland in southern Xinjiang according to the present invention; Figure 2 This is the schematic diagram of the farmland division area in step 2; Figure 3 is the soil organic carbon content at 0-20 cm in different implementation years; Figure 4 It is the soil organic carbon content at 20-40 cm in different implementation years; Figure 5 is the relationship between soil organic carbon content at 0-20 cm and implementation years; Figure 6 It is the relationship between the soil organic carbon content at 20-40cm and the implementation years. DETAILED DESCRIPTION

[0018] The present invention is further described in detail below in conjunction with preferred embodiments. More details are elaborated in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the protection scope of the present invention should not be limited by the content of this specific embodiment.

[0019] The accompanying drawings are schematic diagrams of embodiments of the present invention. It should be noted that the drawings are only examples and are not drawn to scale, and should not be used to limit the actual protection scope of the present invention.

[0020] A method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland is applicable to all areas with low soil organic carbon content, including but not limited to southern Xinjiang. Here, southern Xinjiang is used as an example for illustration. Figure 1 As shown, the specific steps include: Step 1. In the first winter: select a piece of land and spread bio-organic fertilizer, then till the land.

[0021] Step 2. In the spring of the second year: divide the area and plant crops and green manure separately.

[0022] Step 3. In the autumn of the second year: Crush crop straw and green manure, spray diluted EM bacteria solution, ferment to form organic fertilizer and spread it, and then till the land.

[0023] Step 4: Spring of the third year: Plant all crops and remove all straw from the fields after the crops are harvested.

[0024] Repeat steps 1 to 4 to achieve the effect of increasing the organic carbon content and soil carbon sink in farmland soil, thereby quickly increasing the organic carbon content and soil carbon sink in farmland soil; improving soil structure and promoting the formation of soil aggregates; reducing fertilizer input, increasing crop yields, and improving economic benefits; and reducing environmental pollution caused by straw burning and stacking.

[0025] More specifically, step 1 is to select soil with an organic carbon content of less than or equal to 20 g·C·kg -1 , spread bio-organic fertilizer on farmland with salt content less than or equal to 0.4%; after spreading, rotary till the land where bio-organic fertilizer is spread.

[0026] Farmland with low soil organic carbon content has a relatively small organic carbon pool in the soil, and therefore has a greater carbon sequestration potential. After the bio-organic fertilizer is applied to the farmland with low soil organic carbon content, the farmland with low soil organic carbon content can quickly fix a large amount of organic carbon, thereby significantly improving the soil carbon sink.

[0027] The application area of ​​the bio-organic fertilizer is 400-600 kg / mu; the bio-organic fertilizer is a bio-organic fertilizer containing Trichoderma and Bacillus subtilis agents that promote straw decomposition, and the bio-organic fertilizer should be a commercial bio-organic fertilizer that meets the requirements of the "Bio-Organic Fertilizer" (NY884-2012) standard.

[0028] The rotary tillage depth is 20 to 25 cm.

[0029] More specifically, step 2 is to prepare the land and divide it into planting areas and intercropping areas, wherein the planting areas are used for planting crops and the intercropping areas are used for planting green manure.

[0030] Land preparation is a general term for a series of soil cultivation measures before sowing or transplanting crops. The main operations of land preparation include shallow tillage, ploughing, deep loosening, harrowing, hoeing, pressing, leveling, harrowing, ridge formation, and furrowing. The purpose of land preparation is to create a good soil tillage layer structure and surface state, coordinate water, nutrients, air, heat and other factors, improve soil fertility, and provide good conditions for sowing, crop growth, and field management.

[0031] The division of the planting area and the intercropping area means that an intercropping area is set between the two planting areas to form a repeated unit and circulate, such as Figure 2 The width of the planting area is 1.5-2 m, and the width of the intercropping area is 0.4-0.6 m. The crops in the planting area are preferably cotton, wheat, corn, etc., and the green manure in the intercropping area is preferably alfalfa, sesbania, etc.

[0032] As long as step 1 is completed, the land can be demarcated and crops can be planted in the spring of the second year. The specific time is not limited. The time interval between step 1 and step 2 in this embodiment is generally 130 to 150 days in winter in southern Xinjiang.

[0033] More specifically, step 3 is to crush the crop straw and green manure left in the field after the autumn crops are harvested, mix the crushed straw and green manure manually, spray the EM bacterial solution, stack them on the spot, cover them with film, and ferment them to form organic fertilizer. After the fermentation is completed, the organic fertilizer is evenly spread on the field for rotary tillage.

[0034] The lengths of the crop straws and green manure after being crushed are both 2 to 3 cm.

[0035] The EM (Effective Microorganisms, beneficial microorganisms) bacterial liquid, the main components are lactic acid bacteria, Bacillus, nitrifying bacteria, actinomycetes, composite photosynthetic bacteria, active enzymes, photosynthetic catalysts, etc. Each type of microorganism plays an important role, with composite photosynthetic bacteria and lactic acid bacteria as the core. Their synthetic ability supports the activities of other microorganisms, and also uses the substances produced by other microorganisms to form a symbiotic relationship, ensuring that the EM bacterial liquid is stable and fully functional. In the present invention, a 100-300 times EM bacterial liquid dilution is selected.

[0036] The main function of the EM bacterial liquid is to create a benign ecology. It will quickly combine with the benign forces wherever it goes, produce antioxidants, remove oxidants, eliminate corruption, inhibit pathogens, and form a good environment suitable for the growth of animals and plants. At the same time, it also produces a large amount of beneficial substances that are easily absorbed by animals and plants, such as amino acids, organic acids, polysaccharides, various vitamins, various biochemical enzymes, growth-promoting factors, antibiotics and antiviral substances, etc., which improve the immune function of animals and plants and promote healthy growth.

[0037] The crop straw sprayed with EM bacteria solution and green manure are piled on site into a conical pile with a diameter of 0.8-1m and a height of 0.6-0.8m, covered and sealed with a PO film, and fermented at a temperature of 25-35°C for 30-40 days to form organic fertilizer.

[0038] The organic fertilizer is also spread evenly at 400-600 kg / mu.

[0039] The rotary tillage depth is 20 to 25 cm.

[0040] More specifically, the crop planted in step 4 is preferably cotton.

[0041] like Figure 3 , Figure 4 The results show that the soil organic carbon content at 0-20cm and 20-40cm at different implementation years, where BF means before planting; 1yr means one year after planting; 2yr means two years after planting; 3yr means three years after planting; 4yr means four years after planting; 5yr means five years after planting. The results show that the soil organic carbon content at 0-20cm and 20-40cm increased significantly with the implementation years. Among them, the soil organic carbon at 0-20cm before implementation was 8.6g·C·kg -1 After 1, 2, 3, 4, and 5 years, the organic carbon content of the soil increased to 11.6 g·C·kg -1 、18.0g·C·kg -1 , 21.2g·C·kg -1 , 23.7g·C·kg -1 、26.9g·C·kg -1 The a, b, c, ab, and bc in the figure represent the differences between different agricultural products, types of green manure, and years of planting. The results show that different agricultural products, types of green manure, and years of planting will lead to different effects. All differences are less than or equal to 0.05, that is, less than or equal to 5%. The 20-40cm soil organic carbon before implementation was 8.7g·C·kg -1After 1, 2, 3, 4, and 5 years, the organic carbon content of the soil increased to 8.8 g·C·kg -1 、10.0g·C·kg -1 , 13.2g·C·kg -1 、15.3g·C·kg -1 、15.5g·C·kg -1 .

[0042] According to the soil carbon content, linear fitting was performed, with soil carbon content as the Y-axis and implementation years as the X-axis, and the relationship between soil organic carbon content at 0-20 cm and 20-40 cm and implementation years was obtained, as shown in Figure 5 , Figure 6 The results show that the soil organic carbon content at 0-20 cm and the implementation period are expressed as: y=3.63x+5.51, R 2 =0.958; while the soil organic carbon content at 20-40 cm and the implementation period are expressed as: y=1.63x+6.20, R 2 =0.901. 2 The coefficient of determination is represented by 1. The closer the value of the coefficient of determination is to 1, the better the degree of linear fitting is. By adopting the method for promoting the rapid improvement of soil carbon sink in farmland in southern Xinjiang according to the present invention, the average annual increase rate of soil organic carbon in the range of 0 to 20 cm is 3.63 g·C·kg -1 , while the annual average increase rate of soil organic carbon in the 20-40 cm range was 1.63 g·C·kg -1 .

[0043] A method for rapidly improving soil carbon sinks in farmland in southern Xinjiang. First, by returning bio-organic fertilizers and straw to the fields alternately, the organic carbon content and soil carbon sinks in farmland soil can be rapidly increased, soil structure can be improved, and the formation of soil aggregates can be promoted. Secondly, bio-organic fertilizers can be used to reduce the input of chemical fertilizers, increase crop yields, and improve economic benefits. Finally, bio-organic fertilizers are formed by straw fermentation to reduce environmental pollution caused by straw burning and stacking.

[0044] The above content is an explanation of the preferred embodiments of the present invention, which can help those skilled in the art to more fully understand the technical solution of the present invention. However, these embodiments are merely illustrative, and it cannot be determined that the specific implementation methods of the present invention are limited to the description of these embodiments. For ordinary technicians in the technical field to which the present invention belongs, without departing from the concept of the present invention, several simple deductions and transformations can be made, which should be regarded as belonging to the protection scope of the present invention.

Claims

1. A method for promoting rapid improvement of soil carbon sink in farmland in southern Xinjiang, characterized in that: Specifically include: Step 1: Winter of the first year: Select a site and spread bio-organic fertilizer, then till the soil; Step 2: In the spring of the second year: divide the area and plant crops and green manure separately; Step 3, in the autumn of the second year: crush the crop straw and green manure, spray the diluted EM bacteria solution, ferment it to form organic fertilizer and spread it, and then till the soil; Step 4: Spring of the third year: Plant all crops and remove all straw from the fields after the crops are harvested.

2. A method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 1, characterized in that: The step 1 is to select soil with organic carbon content less than or equal to 20g·C·kg -1 , spread bio-organic fertilizer on farmland with salt content less than or equal to 0.4%; after spreading, rotary till the land where bio-organic fertilizer is spread.

3. A method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 2, characterized in that: The spreading area of ​​the bio-organic fertilizer is 400-600 kg / mu; the bio-organic fertilizer contains Trichoderma and Bacillus subtilis; and the rotary tillage depth is 20-25 cm.

4. The method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 1, characterized in that: The step 2 is to prepare the land and divide it into planting areas and intercropping areas, wherein the planting areas are used for planting crops and the intercropping areas are used for planting green manure.

5. A method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 4, characterized in that: The division into planting areas and intercropping areas means that an intercropping area is set between two planting areas to form a repeated unit and circulate; the width of the planting area is 1.5 to 2 m, and the width of the intercropping area is 0.4 to 0.6 m.

6. The method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 1, characterized in that: After the crops are harvested, the crop straw and green manure left in the field are crushed, the crushed straw and green manure are fully mixed, and after spraying EM bacterial solution, they are stacked on the spot, covered with film, and fermented to form organic fertilizer; after the fermentation is completed, the organic fertilizer is evenly spread on the field and rotary tilled.

7. A method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 6, characterized in that: The lengths of the crop straws and green manure after being crushed are both 2 to 3 cm; and the EM bacterial solution is a 100 to 300-fold diluted EM bacterial solution.

8. The method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 6, characterized in that: The crop straw sprayed with EM bacteria solution and green manure are piled on site into a conical pile with a diameter of 0.8-1m and a height of 0.6-0.8m, covered and sealed with a PO film, and fermented at a temperature of 25-35°C for 30-40 days to form organic fertilizer.

9. The method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 6, characterized in that: The organic fertilizer is evenly spread at 400-600 kg / mu; the rotary tillage depth is 20-25 cm.

10. The method for promoting rapid improvement of soil carbon sink in southern Xinjiang farmland according to claim 1, characterized in that: Repeat steps 1 to 4 to increase the organic carbon content and soil carbon sink in farmland soil.

Images