A device for detecting the organic carbon activation effect of straw returned to field soil

Abstract

This utility model belongs to the field of crop carbon conversion measurement technology, and specifically discloses a device for detecting the soil organic carbon activation effect of straw return to the field. It includes a planting unit, a first soil detection unit and a gas detection unit. Crops are planted in the planting unit, and then the liquid phase sample of the soil is detected in real time using the first soil unit. Then, the carbon content of the gas in the planting unit is detected using the gas detection unit, so as to obtain the dynamic changes of the organic carbon activation effect during the straw return process.

Description

Technical Field

[0001] This utility model relates to the field of crop carbon conversion measurement technology, and in particular to a device for detecting the activation effect of soil organic carbon when straw is returned to the field. Background Technology

[0002] Returning straw to the field is an effective way to utilize straw resources, which has a positive impact on ensuring grain productivity and promoting a virtuous cycle of soil.

[0003] Current research on organic carbon conversion from straw return to the field mainly relies on off-field detection methods. These methods require collecting soil / gas samples and bringing them back to the laboratory for subsequent testing and analysis. However, off-field detection typically only reflects the soil organic carbon conversion effect at the sampling time point. The metabolic activity of microorganisms under straw return can fluctuate significantly within a range of minutes to hours. Off-field detection cannot promptly capture and report on short-term soil carbon conversion and activation effects, potentially leading to data lag and inaccuracy, and failing to reflect dynamic changes in real time. Therefore, there is an urgent need for a device capable of real-time monitoring of the soil organic carbon conversion process under straw return to the field. Utility Model Content

[0004] The purpose of this invention is to provide a device for detecting the soil organic carbon activation effect of straw returning to the field, so as to solve one or more technical problems existing in the prior art, and at least provide a beneficial option or create conditions.

[0005] The solution to the technical problem of this utility model is: A device for detecting the soil organic carbon activation effect of straw returning to the field, comprising: A planting unit includes a soil column, wherein a growth section and a soil section are arranged sequentially from top to bottom within the soil column; The first soil testing unit includes a collection tube, an extraction component, a dilution component, and a testing component connected in sequence. The end of the collection tube away from the extraction component is connected to the soil portion. The extraction component can extract the accumulated liquid in the soil portion and transport it to the dilution component. The testing component includes a total organic carbon analyzer and an ultraviolet spectrometer. Both the total organic carbon analyzer and the ultraviolet spectrometer are connected to the output end of the dilution component. The gas detection unit includes a gas collection hood and a carbon emission monitoring and analysis instrument. The gas collection hood is installed on the soil column and connected to the growth section. The gas collection hood is connected to the carbon emission monitoring and analysis instrument through a ventilation pipe.

[0006] This technical solution has at least the following beneficial effects: First, it enables real-time monitoring of the entire process of organic carbon conversion in soil during straw return. Throughout the straw return process, by monitoring the dynamics of carbon dioxide and other carbon gas emissions from soil respiration, it allows for real-time analysis of soil organic carbon and dissolved organic carbon content and UV-Vis spectral characteristics from straw-derived carbon conversion. Combined with timely capture of real-time changes in environmental factors such as redox potential, pH, temperature, and oxygen, it allows for more accurate observation and study of the direction (positive / negative) and intensity of the straw return effect on soil organic carbon. This optimizes field management practices and contributes to achieving the dual goals of carbon sequestration and emission reduction. Second, in-situ sampling avoids the data distortion problems caused by continued microbial metabolism and gas emissions during sample transportation and processing in traditional off-field testing, ensuring that the test data accurately reflects the actual state of soil organic carbon conversion in the field.

[0007] As a further improvement to the above technical solution, the soil section is connected to a bacterial inlet channel, and the bacterial inlet channel is provided with inlet holes along the circumference.

[0008] By adopting the above technical solution, researchers can introduce putrefactive bacteria into the incubation channel to address the situation where the number of microorganisms is insufficient or their activity is low in the early stage of straw decomposition. This allows the straw to degrade rapidly, thereby accelerating the conversion of soil organic carbon, thus speeding up the overall experiment and reducing the required time.

[0009] As a further improvement to the above technical solution, multiple inoculation channels are provided, and the multiple inoculation channels are arranged along the length direction of the soil section.

[0010] By adopting the above technical solution, the introduced microbial strains or mixed microbial communities can be more evenly distributed in different areas of the soil. Compared with a single inoculation channel, this layout avoids the problem of microorganisms being concentrated in one area and insufficiently distributed in other areas, ensuring the consistency of the overall microbial community structure and activity in the soil, and making the environmental conditions for soil organic carbon transformation more stable during the experiment.

[0011] As a further improvement to the above technical solution, a second soil detection unit is also included, which includes a temperature and humidity sensor, a unit collector, and a data storage display. The sensing end of the temperature and humidity sensor is installed inside the soil section, the temperature and humidity sensor is electrically connected to the collector, and the collector is electrically connected to the data storage display.

[0012] By adopting the above technical solution, temperature and humidity sensors can be used to monitor the temperature and humidity data inside the soil in real time. The data acquisition device then collects and processes the real-time data obtained by the sensors and transmits it to the data storage display for storage and display. Compared with traditional manual timed measurement, this design can achieve high-frequency and continuous monitoring of soil temperature and humidity, timely capture changes in soil in a short period of time, and provide continuous and stable data support for research.

[0013] As a further improvement to the above technical solution, multiple temperature and humidity sensors are provided, and the multiple temperature and humidity sensors are arranged along the length direction of the soil section.

[0014] By adopting the above technical solution, the temperature and humidity of actual farmland soil exhibit spatial heterogeneity at different depths and horizontal positions. Multiple sensors are arranged along the length of the soil to monitor the temperature and humidity changes in different areas of the soil in real time and accurately capture the gradient differences in soil temperature and humidity in the horizontal direction.

[0015] As a further improvement to the above technical solution, a filter assembly is also provided between the extraction component and the soil column. The filter assembly includes a filter box and multiple filter screens arranged in the filter box along the direction from near to far from the soil column. One end of the filter box is connected to the liquid collection pipe and the other end is connected to the extraction component.

[0016] By adopting the above technical solution, it is possible that impurities such as silt and sand may be present in the soil slurry. These objects, once they enter the detection component, may clog the instrument tubing or interfere with the detection results. The multi-layered filter in the filtration component can filter the soil slurry step by step, effectively intercepting everything from large particles to fine suspended solids. This ensures that the samples entering the total organic carbon analyzer, ultraviolet spectrometer, and other detection equipment are pure, avoiding detection errors caused by impurities and significantly improving the accuracy and reliability of the data.

[0017] As a further improvement to the above technical solution, the gas collection hood includes a first hood and a second hood, the height of the first hood is greater than the height of the second hood, and both the first hood and the second hood can be detachably installed on the soil column.

[0018] During the experiment, carbon conversion experiments were conducted in both the absence of crops and the presence of crops. To accommodate the height of the crops, a first cover with a relatively large height was installed in advance during the carbon conversion experiment with crops, so that the crops had enough space to grow.

[0019] As a further improvement to the above technical solution, the planting unit also includes an inlet pipe and an outlet pipe, the inlet pipe being connected to the growth section and the outlet pipe being connected to the bottom of the soil column.

[0020] By employing the above technical solution, water can be precisely injected into the growth section through the inlet pipe to simulate soil moisture changes under different rainfall intensities or irrigation conditions, meeting the diverse soil moisture requirements of the experiment. Meanwhile, the outlet pipe can promptly drain excess water, preventing soil waterlogging and avoiding the negative impact of excessive humidity on microbial activity or the creation of an anaerobic environment. The combination of these two methods enables dynamic regulation and precise control of soil moisture, providing stable and controllable experimental conditions for studying the effects of soil moisture on straw decomposition and organic carbon conversion.

[0021] As a further improvement to the above technical solution, the gas collection hood is provided with an opening, and an air exchange fan is provided at the opening.

[0022] By adopting the above technical solution, the ventilation fan continuously introduces fresh air from the outside and exhausts high-concentration gases, which can prevent the gas concentration in the gas collection hood from becoming saturated, ensure the accuracy and effectiveness of the detection data, and enable the instrument to continuously and stably monitor the dynamics of soil carbon release.

[0023] As a further improvement to the above technical solution, the height of the soil column is 50 cm and the height of the soil section is 35 cm.

[0024] By adopting the above technical solution and pre-setting the height of the soil column, the actual landform can be simulated as much as possible, thereby improving the reliability of the experimental data. Attached Figure Description

[0025] To more clearly illustrate the technical solutions in the embodiments of this utility model, the accompanying drawings used in the description of the embodiments will be briefly explained below. Obviously, the described drawings are only a part of the embodiments of this utility model, and not all of them. Those skilled in the art can obtain other design schemes and drawings based on these drawings without creative effort.

[0026] Figure 1 This is a schematic diagram of the structure of a device for detecting the activating effect of straw returning to the field on soil organic carbon, according to this utility model. Attached image description: 1. Soil column; 11. Growth section; 12. Soil section; 13. Water inlet pipe; 14. Water outlet pipe; 2. First soil detection unit; 21. Liquid collection pipe; 22. Extraction assembly; 23. Dilution assembly; 24. Total organic carbon analyzer; 25. Ultraviolet spectrometer; 26. Filter assembly; 3. Gas detection unit; 31. Air inlet hood; 32. Carbon emission monitoring and analysis instrument; 33. Ventilation fan; 4. Second soil detection unit; 41. Temperature and humidity sensor; 42. Unit data logger; 43. Data storage display; 44. Soil oxygen sensor; 5. Inoculation channel. Detailed Implementation

[0028] The embodiments of this utility model are described in detail below. Examples of these embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain this utility model, and should not be construed as limiting this utility model.

[0029] In the description of this utility model, it should be understood that the directional descriptions, such as up, down, front, back, left, right, etc., indicate the directional or positional relationship based on the directional or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model.

[0030] In the description of this utility model, "several" means one or more, "multiple" means two or more, "greater than," "less than," and "exceeding" are understood to exclude the stated number, while "above," "below," and "within" are understood to include the stated number. If "first" or "second" is used in the description, it is only for the purpose of distinguishing technical features and should not be construed as indicating or implying relative importance, or implicitly indicating the number of indicated technical features, or implicitly indicating the order of the indicated technical features.

[0031] In the description of this utility model, unless otherwise explicitly defined, terms such as "setting," "installation," and "connection" should be interpreted broadly, and those skilled in the art can reasonably determine the specific meaning of the above terms in this utility model in conjunction with the specific content of the technical solution.

[0032] Existing studies on the organic carbon activation effect of straw returning to the field usually require collecting soil samples from the field and bringing them to the laboratory for testing and analysis. However, in this experimental method, the soil in the field may undergo significant changes in a short period of time. The laboratory can only obtain data at the time of collection and cannot obtain data after the soil changes in a timely manner. Furthermore, it is difficult to reflect the dynamic changes in the carbon activation effect in the soil. Therefore, this application provides a device for detecting the organic carbon activation effect of straw returning to the field.

[0033] Reference Figure 1 This application provides a real-time monitoring device for the soil organic carbon conversion process during straw return to the field, which includes a planting unit, a first soil detection unit 2 and a gas detection unit 3. Crops are planted in the planting unit, and then the liquid phase sample of the soil is detected in real time using the first soil unit. Then, the carbon content of the gas in the planting unit is detected using the gas detection unit 3, thereby obtaining the dynamic changes of the organic carbon activation effect during the straw return to the field.

[0034] Specifically, the planting unit includes a soil column 1, within which a growth section 11 and a soil section 12 are arranged sequentially from top to bottom. The first soil detection unit 2 includes a liquid collection pipe 21, an extraction component 22, a dilution component 23, and a detection component connected in sequence. The end of the liquid collection pipe 21 away from the extraction component 22 is connected to the soil section 12. The extraction component 22 can extract the accumulated liquid in the soil section 12 and transport it to the dilution component 23. The detection component includes a total organic carbon analyzer 24 and an ultraviolet spectrometer 25, both of which are connected to the output end of the dilution component 23. The gas detection unit 3 includes a gas collection hood 31 and a carbon emission monitoring and analysis instrument 32. The gas collection hood 31 covers the soil column 1 and is connected to the growth section 11. The gas collection hood 31 is connected to the carbon emission monitoring and analysis instrument 32 through a ventilation pipe. A collector is installed on the ventilation pipe, and the collector periodically delivers the gas to the carbon emission monitoring and analysis instrument 32 for detection and analysis.

[0035] As can be seen from the above, firstly, it enables real-time monitoring of the entire process of organic carbon conversion in soil after straw return to the field. The first soil detection unit 2 can obtain soil liquid phase samples in real time, and the gas detection unit 3 can detect the soil respiration rate. This changes the limitation of traditional off-field testing, which can only reflect static data at the time of sampling, and timely captures and provides feedback on soil carbon conversion and activation effects in a short period of time. Secondly, in-situ sampling avoids the data distortion problems caused by factors such as continued microbial metabolism and gas escape during sample transportation and processing in traditional off-field testing, ensuring that the test data truly reflects the actual state of organic carbon conversion in the field soil.

[0036] Specifically, in this embodiment, the extraction component 22 includes a vacuum pump and an extraction tank, and the dilution component 23 includes a dilution tank and an ultrapure water system. The vacuum pump is connected to the collection pipe 21 and is used to create a vacuum inside the collection pipe 21. One end of the extraction tank is connected to the collection pipe 21 and the other end is connected to the dilution tank. The end of the dilution tank away from the extraction tank has two branches, which are respectively connected to the total organic carbon analyzer 24 and the ultraviolet spectrometer 25. The ultrapure water system is connected to the dilution tank, and a stirrer is provided inside the dilution tank.

[0037] As a further embodiment, the soil section 12 is connected to a bacterial inlet channel 5. The end of the bacterial inlet channel 5 that penetrates into the soil column 1 has multiple bacterial inlet holes along the circumference. The end of the bacterial inlet channel 5 that exits from the soil column 1 has a bacterial inlet control valve. When it is necessary to transport the putrefactive bacterial solution into the soil column 1, simply open the bacterial inlet control valve and transport the bacterial solution into the soil section 12 through the hose and funnel.

[0038] This scheme addresses the issue of insufficient microbial numbers or low activity in the early stages of straw decomposition. Researchers can utilize the inoculation channel 5 to introduce putrefactive bacteria, enabling rapid straw degradation and accelerating soil organic carbon conversion. This, in turn, speeds up the overall experiment and reduces the required time. Furthermore, the inoculation channel 5 can be used to introduce microbial strains with different degradation capabilities into the soil portion 12 of different soil columns 1. The effects of these strains on straw organic carbon conversion efficiency, activating effect intensity, and carbon conversion pathways can be compared and analyzed. This provides data support for screening dominant microbial strains that promote efficient straw decomposition and enhance soil carbon sequestration capacity, and also improves the utilization rate of the experimental soil column 1.

[0039] In order to fully cultivate microbial communities in all parts of the soil section 12 of the soil column 1, in this embodiment, multiple microbial entry channels 5 are provided, which are arranged along the length of the soil section 12. By adopting this design, the introduced microbial species are more evenly distributed in different areas of the soil section 12. Compared with a single microbial entry channel 5, this layout avoids the problem of microorganisms being concentrated in some areas and insufficiently distributed in other areas, ensuring the consistency of the overall microbial community structure and activity of the soil section 12, and making the environmental conditions for soil organic carbon conversion more stable during the experiment.

[0040] Furthermore, each of the inlet channels 5 is equipped with a control valve.

[0041] Soil temperature and humidity are key environmental factors affecting soil microbial activity, straw decomposition rate, and organic carbon conversion process. To ensure that researchers can fully understand the physical state of the soil section 12 and make real-time adjustments to it, the straw return organic carbon activation effect detection device of this application also includes a second soil detection unit 4, which includes a temperature and humidity sensor 41, a unit collector 42, and a data storage display 43. The sensing end of the temperature and humidity sensor 41 is installed inside the soil section 12 and is electrically connected to the collector. The unit collector 42 is electrically connected to the data storage display 43. The temperature and humidity sensor 41 can monitor the temperature and humidity data inside the soil section 12 in real time. The collector then collects and processes the real-time data obtained by the sensor and transmits it to the data storage display 43 for storage and display. Compared with traditional manual timed measurement, this design can achieve high-frequency and continuous monitoring of soil temperature and humidity, timely capture changes in soil conditions in a short period of time, and provide continuous and stable data support for research.

[0042] Furthermore, the second soil detection unit 4 also includes a soil oxygen sensor 44. The sensing end of the soil oxygen sensor 44 is installed inside the soil section 12. The soil oxygen sensor 44 is electrically connected to the data acquisition unit and the data storage display 43, so that the data storage display 43 can simultaneously display the temperature, humidity and oxygen concentration at various locations in the soil, allowing the experimenters to fully understand the physical properties at various locations in the soil section 12 and improve the accuracy and reliability of the experiment.

[0043] Furthermore, multiple temperature and humidity sensors 41 are provided, arranged along the length of the soil section 12. The temperature and humidity of actual farmland soil exhibit spatial heterogeneity at different depths and horizontal positions. With multiple sensors arranged along the length of the soil section 12, the temperature and humidity changes in different areas of the soil can be monitored in real time, accurately capturing the gradient differences in soil temperature and humidity in the horizontal direction.

[0044] When the liquid in the soil section 12 is extracted to the detection component, the mud and sand in the soil section 12 may be extracted to the detection component at the same time, thereby clogging the pipeline or interfering with the detection results. Therefore, a filter component 26 is also provided between the extraction component 22 and the soil column 1. The filter component 26 includes a filter box and multiple filter screens arranged at intervals in the filter box along the direction from close to away from the soil column 1. One end of the filter box is connected to the liquid collection pipe 21 and the other end is connected to the extraction component 22. Filter holes are opened on the multiple filter screens. The diameter of the filter holes on the filter screens gradually decreases along the direction from close to away from the soil column 1. The multi-layer filter in the filter assembly 26 can filter the soil slurry step by step, effectively intercepting everything from large particles to fine suspended matter, ensuring the purity of the samples entering the total organic carbon analyzer 24, ultraviolet spectrometer 25 and other detection equipment, avoiding detection errors caused by impurities, and significantly improving the accuracy and reliability of the data.

[0045] Because the proportions of the growth section 11 and the soil section 12 in the soil column 1 are fixed, and the experiment requires experience in carbon conversion experiments without crop planting and carbon conversion experiments with crop planting, in order to adapt to the growth height after crop planting, in this embodiment, the gas collection hood 31 includes a first hood and a second hood. The height of the first hood is greater than the height of the second hood. Both the first hood and the second hood can be detachably installed on the soil column 1 and cover the production section. Specifically, either the first hood or the second hood can be detachably installed on the production section and seal the opening of the soil column 1, so that the gas generated in the soil column 1 can enter the carbon emission monitoring and analysis instrument 32 through the gas collection hood 31. When conducting carbon conversion experiments with crop planting, the first hood with a larger height is installed in advance so that the crops have enough space to grow.

[0046] Specifically, the bottom of the gas collection hood 31 is provided with an opening that engages with the top of the soil column 1. A rubber ring is vertically placed on the opening of the gas collection hood 31. The gas collection hood 31 is fixedly engaged with the top of the soil column 1 by a buckle. In this embodiment, the specific style of the buckle is not limited.

[0047] The gas collection hood 31 has an opening, and an air exchange fan 33 is installed at the opening. The air exchange fan 33 continuously introduces fresh air from the outside and exhausts high-concentration gas, which can prevent the gas concentration inside the gas collection hood 31 from becoming saturated, ensuring the accuracy and validity of the detection data, and enabling the instrument to continuously and stably monitor the dynamics of soil carbon release. During the collection process, the opening is closed to ensure uniform gas mixing at the top of the soil column 1, and the top is opened during non-collection processes to ensure air circulation at the top of the soil column 1.

[0048] In order to accurately control the moisture in the soil column 1, in this embodiment, the planting unit also includes an inlet pipe 13 and an outlet pipe 14. The inlet pipe 13 is connected to the side wall of the growth section 11, and the outlet pipe 14 is connected to the bottom side wall of the soil column 1. Both the inlet pipe 13 and the outlet pipe 14 are equipped with control valves and flow meters. When replenishing water in the soil column 1, the control valve on the outlet pipe 14 is closed first, and then the control valve on the inlet pipe 13 is opened, and water is injected into the inlet pipe 13. At the same time, the flow meter is observed until a predetermined volume of water is injected.

[0049] Water can be precisely injected into the growth section 11 through the inlet pipe 13 to simulate soil moisture changes under different rainfall intensities or irrigation conditions, meeting the diverse soil moisture requirements of the experiment. Meanwhile, the outlet pipe 14 can promptly drain excess water, preventing soil waterlogging and avoiding the negative impact of excessive humidity on microbial activity or the creation of an anaerobic environment. Together, these two systems achieve dynamic regulation and precise control of soil moisture, providing stable and controllable experimental conditions for studying the effects of soil moisture on straw decomposition and organic carbon conversion.

[0050] As a further embodiment of this application, the height of the soil column 1 is 50 cm, the height of the soil part 12 is 35 cm, and a filling part with a height of 5 cm is also provided below the soil part 12. The filling part is filled with perlite, and the drainage pipe is connected to the filling part.

[0051] Furthermore, the straw return to the field organic carbon activation effect detection device also includes an installation cabinet, which can house the carbon emission monitoring and analysis instrument 32, the total organic carbon analyzer 24, the ultraviolet spectrometer 25, the unit collector 42, and the data storage display 43. The installation cabinet is made of waterproof and rustproof materials to ensure that it is not affected by the environment, thereby reducing interference to the internal instruments and equipment.

[0052] The preferred embodiments of the present invention have been described in detail above, but the present invention is not limited to the described embodiments. Those skilled in the art can make various equivalent modifications or substitutions without departing from the spirit of the present invention, and these equivalent modifications or substitutions are all included within the scope defined by the claims of this application.

Claims

1. A device for detecting the soil organic carbon activation effect of straw returning to the field, characterized in that, include: The planting unit includes a soil column (1), in which a growth part (11) and a soil part (12) are arranged sequentially from top to bottom; The first soil testing unit (2) includes a collection pipe (21), an extraction component (22), a dilution component (23), and a testing component connected in sequence. The end of the collection pipe (21) away from the extraction component (22) is connected to the soil section (12). The extraction component (22) can extract the accumulated liquid in the soil section (12) and transport it to the dilution component (23). The testing component includes a total organic carbon analyzer (24) and an ultraviolet spectrometer (25). The total organic carbon analyzer (24) and the ultraviolet spectrometer (25) are both connected to the output end of the dilution component (23). The gas detection unit (3) includes a gas collection hood (31) and a carbon emission monitoring and analysis instrument (32). The gas collection hood (31) is placed on the soil column (1) and connected to the growth section (11). The gas collection hood (31) is connected to the carbon emission monitoring and analysis instrument (32) through a ventilation pipe.

2. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, The soil section (12) is connected to a fungus entry channel (5), and the fungus entry channel (5) has fungus entry holes along the circumference.

3. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 2, characterized in that, Multiple inoculum channels (5) are provided, and the multiple inoculum channels (5) are arranged along the length direction of the soil section (12).

4. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, It also includes a second soil detection unit (4), which includes a temperature and humidity sensor (41), a unit collector (42) and a data storage display (43). The sensing end of the temperature and humidity sensor (41) is installed inside the soil part (12). The temperature and humidity sensor (41) is electrically connected to the collector, and the collector is electrically connected to the data storage display (43).

5. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 4, characterized in that, Multiple temperature and humidity sensors (41) are provided, and the multiple temperature and humidity sensors (41) are arranged along the length direction of the soil part (12).

6. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, A filter assembly (26) is also provided between the extraction assembly (22) and the soil column (1). The filter assembly (26) includes a filter box and multiple filter screens arranged in the filter box along the direction from close to to far away from the soil column (1). One end of the filter box is connected to the liquid collection pipe (21), and the other end is connected to the extraction assembly (22).

7. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, The gas collection hood (31) includes a first hood and a second hood. The height of the first hood is greater than the height of the second hood. Both the first hood and the second hood can be detachably installed on the soil column (1).

8. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, The planting unit also includes an inlet pipe (13) and an outlet pipe (14), the inlet pipe (13) being connected to the growth section (11) and the outlet pipe (14) being connected to the bottom of the soil column (1).

9. The device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, An opening is provided on the gas collection hood (31), and an air exchange fan (33) is provided at the opening.

10. A device for detecting the soil organic carbon activation effect of straw return to the field according to claim 1, characterized in that, The height of the soil column (1) is 50 cm, and the height of the soil section (12) is 35 cm.

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