A soil carbon flux monitoring device and a whole-soil profile warming test device

Abstract

This invention discloses a soil carbon flux monitoring device, comprising a total respiration carbon flux monitoring device and a heterotrophic respiration carbon flux monitoring device. The total respiration carbon flux monitoring device includes a shallow respiration ring, within which at least two sets of gas well components at different depths are embedded. The heterotrophic respiration carbon flux monitoring device includes a deep respiration ring, within which are embedded gas well components identical to those in the shallow respiration ring. This invention also discloses a whole-soil profile warming test device. This invention, by combining the total respiration carbon flux monitoring device and the heterotrophic respiration carbon flux monitoring device with gas well components at different depths, achieves refined separation and collection of total respiration, heterotrophic respiration, and autotrophic respiration fluxes at different soil layers. This allows for precise quantification of the response characteristics of carbon dynamics in different soil layers to climate warming, providing crucial data support for constructing soil carbon cycle models with vertical stratification parameters and improving the accuracy of global carbon budget predictions.

Description

Technical Field

[0001] This invention relates to the field of global change and soil ecology technology, specifically to a soil carbon flux monitoring device and a whole-soil profile warming test device. Background Technology

[0002] Climate warming drives a positive feedback loop between soil and atmosphere carbon, creating a vicious cycle of "increased soil carbon release → declining carbon sink function → intensified warming," exacerbating the global climate crisis. Soil respiration, as a core biological process of releasing carbon from soil into the atmosphere, is a key flux link in the carbon cycle of terrestrial ecosystems. Essentially, it is the process of CO2 production through soil biological metabolism, including autotrophic respiration primarily driven by plant roots and heterotrophic respiration primarily driven by soil microorganisms decomposing organic matter. These two processes together constitute the total soil respiration flux. Studies show that the annual CO2 released by soil respiration can reach more than 10% of the total atmospheric carbon pool, far exceeding the annual emissions of fossil fuels from humans. Even small changes in soil respiration can significantly affect the climate system through the carbon cycle feedback mechanism, making it a core observational indicator for quantifying the carbon balance of terrestrial ecosystems.

[0003] However, current soil carbon flux measurements suffer from significant spatial limitations, with monitoring highly concentrated in the 0-10 cm soil surface layer. Due to technological constraints, systematic detection of soil carbon fluxes in deeper soil layers (10-100 cm) is lacking. Deep soil layers (10-100 cm) account for over 50% of global soil organic carbon storage. Because their physicochemical properties and biological community composition differ from the surface layer, their response to climate warming and the underlying mechanisms remain unclear. Traditional measurement methods lack the ability to systematically observe carbon fluxes in deep soil layers, resulting in a lack of vertical stratification parameters in soil carbon cycle models. This leads to a lack of understanding of the vertical stratification patterns of soil carbon pools, directly impacting the predictive accuracy of global carbon budget models and becoming a key bottleneck restricting research on climate warming responses.

[0004] The present invention addresses the above-mentioned technical problems. Summary of the Invention

[0005] To address the existing technical problems, this invention provides a soil carbon flux monitoring device and a whole-soil profile warming test device to solve the problems in the prior art.

[0006] To achieve the above-mentioned objectives, the present invention provides the following technical solution:

[0007] A soil carbon flux monitoring device includes a total respiration carbon flux monitoring device and a heterotrophic respiration carbon flux monitoring device;

[0008] The total respiratory carbon flux monitoring device includes a shallow breathing ring, in which at least two sets of gas well components at different depths are embedded, with the shallow breathing ring having a depth of 5-10 cm. The heterotrophic respiratory carbon flux monitoring device includes a deep breathing ring, in which the same gas well components as those in the shallow breathing ring are embedded, with a depth of 20-100 cm.

[0009] The above technical solution collects gases from soil at different depths using a total respiration carbon flux monitoring device, and then calculates the total respiration carbon flux corresponding to different soil depths. It also collects gases from soil at different depths using a heterotrophic respiration carbon flux monitoring device, and then calculates the heterotrophic respiration carbon flux corresponding to different soil depths. The difference between the two can be used to calculate the autotrophic respiration carbon flux corresponding to different soil depths. This achieves a three-dimensional analysis system for soil total respiration, heterotrophic respiration (microorganism-driven), and autotrophic respiration (root-dominated) at different soil depths through precise stratified design of differentiated depth gas well components, enabling refined separation and quantitative monitoring of carbon flux in the entire soil profile from 0 to 100 cm.

[0010] Preferably, the gas well assembly includes a base, the lower end of which is connected to a hollow pipe, the lower end of which is connected to a porous pipe, the porous pipe having through holes distributed on its wall, the lower end of which is connected to a drill bit, a gas extraction chamber inside the hollow pipe, the lower end of which is connected to the upper end of the porous pipe, and a gas guide pipe connected to the upper end of the gas extraction chamber, one end of which is connected to the gas extraction chamber, and the other end of which extends out of the hollow pipe and is connected to a triangular valve.

[0011] Preferably, the hollow tube has scale lines marked on its wall.

[0012] Preferably, the air extraction chamber has a hollow columnar structure.

[0013] Preferably, the shallow breathing ring is embedded with three sets of air well components at different depths, and the deep breathing ring is embedded with the same three sets of air well components as the shallow breathing ring. The first set of air well components has a depth of 0-10 cm, the second set has a depth of 10-30 cm, and the third set has a depth of 30-60 cm.

[0014] Preferably, the shallow breathing ring is embedded with four sets of air well components at different depths, and the deep breathing ring is embedded with the same four sets of air well components as the shallow breathing ring. The first set of air well components has a depth of 0-10cm, the second set has a depth of 10-30cm, the third set has a depth of 30-60cm, and the fourth set has a depth of 60-100cm.

[0015] A whole-soil profile warming test device includes a future climate simulation device and a current climate simulation device;

[0016] The current climate simulation device includes a current climate shell, and the future climate simulation device includes a future climate shell. Both the future climate shell and the current climate shell are equipped with a soil carbon flux monitoring device as described above. The future climate shell is equipped with a heating mechanism and a temperature sensor, which are electrically connected to a temperature controller.

[0017] This setup combines soil carbon flux monitoring devices with intelligent temperature control devices to warm the entire soil profile under natural conditions. It constructs an integrated system of "stratified monitoring - profile temperature control - dynamic response" for soil profile carbon flux assessment, explores the impact of future and current climate on the dynamic vertical stratification of soil profile carbon under natural conditions, and tracks the dynamic response characteristics of carbon flux at each soil depth to warming in real time.

[0018] Preferably, both the future climate shell and the current climate shell have a ring-shaped structure;

[0019] The heating mechanism includes an annular heating coil and multiple heating rods. The heating coil is disposed inside the future climate shell and is concentrically arranged with the future climate shell. The heating rods are evenly distributed along the outer periphery of the future climate shell and extend along the depth direction of the future climate shell.

[0020] Both the future climate housing and the current climate housing are equipped with humidity sensors.

[0021] Compared with existing technologies, the beneficial effects of this invention are as follows: This invention measures the total respiration carbon flux in shallow soil using a total respiration carbon flux monitoring device, and assesses the soil microbial respiration carbon flux using a heterotrophic respiration carbon flux monitoring device. The difference between the two data points can be used to obtain the plant root respiration carbon flux. By combining gas well components at different depths, it achieves refined separation and collection of total respiration, heterotrophic respiration (microorganism-dominated), and autotrophic respiration (root-dominated) carbon fluxes in different soil layers at different depths. This technology overcomes the monitoring blind spots and observation limitations of traditional methods, and can accurately quantify the response characteristics of various carbon flux components in different soil layers to climate warming. It provides key data support for constructing soil carbon cycle models with vertical stratification parameters and improving the accuracy of global carbon budget prediction. It also lays a technical and scientific foundation for revealing the feedback mechanism of soil ecosystem carbon cycle and optimizing soil health management strategies. Attached Figure Description

[0022] Figure 1 This is a schematic diagram of the structure of the gas well assembly of the present invention;

[0023] Figure 2This is a schematic diagram of the structure of a first embodiment of the soil carbon flux monitoring device of the present invention;

[0024] Figure 3 This is a schematic diagram of the structure of a second embodiment of the soil carbon flux monitoring device of the present invention;

[0025] Figure 4 This is a schematic diagram of the structure of Embodiment 3 of the soil carbon flux monitoring device of the present invention;

[0026] Figure 5 This is a schematic diagram of the structure of a first embodiment of the full-section heating test device of the present invention;

[0027] Figure 6 This is a schematic diagram of the structure of Embodiment 2 of the full-section heating test device of the present invention;

[0028] Figure 7 This is a schematic diagram of the structure of Embodiment 3 of the full-section heating test device of the present invention;

[0029] Figure 8 This is a top view of Embodiment 3 of the full-section heating test device of the present invention;

[0030] Figure 9 This is a graph showing the response of carbon flux in soil profiles at different depths to climate warming.

[0031] Figure label:

[0032] 1. Shallow breathing ring, 2. Deep breathing ring, 3. Gas well assembly, 31. Base, 32. Hollow tube, 33. Pumping chamber, 34. Porous tube, 35. Drill bit, 36. Gas guide tube, 37. Triangular valve, 38. Scale line, 4. Future climate shell, 5. Heating coil, 6. Heating rod, 7. Temperature controller, 8. Current climate shell, 91. Temperature sensor, 92. Humidity sensor. Detailed Implementation

[0033] The present invention will be further described in detail below with reference to embodiments and specific implementation methods. However, this should not be construed as limiting the scope of the above-described subject matter of the present invention to the following embodiments; all technologies implemented based on the content of the present invention fall within the scope of the present invention.

[0034] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this invention 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 invention.

[0035] Example 1 of a soil carbon flux monitoring device

[0036] As attached Figure 1 and attached Figure 2 As shown, a soil carbon flux monitoring device includes a total respiration carbon flux monitoring device and a heterotrophic respiration carbon flux monitoring device. The total respiration carbon flux monitoring device includes a shallow respiration ring 1, which has two sets of gas well components 3 embedded at different depths. The depth of the shallow respiration ring 1 is 5-10 cm. The heterotrophic respiration carbon flux monitoring device includes a deep respiration ring 2, which has two sets of gas well components 3 embedded within it, identical to those in the shallow respiration ring 1. The gas well components 3 in the deep respiration ring 2 are the same as those in the shallow respiration ring 1, and the depth of the deep respiration ring 2 is 20-100 cm. One set of gas well components 3 has a depth of 0-10 cm, and the other set has a depth of 10-30 cm. The depth of the shallow respiration ring 1 is not less than the depth of the shallower gas well component 3, and the depth of the deep respiration ring 2 is not less than the depth of the deeper gas well component 3.

[0037] refer to Figure 1 The gas well assembly 3 includes a base 31, which is composed of a cylinder with an upper diameter of 5 cm and a middle diameter of 2 cm. The bottom of the base 31 is composed of a hollow cylinder with an inner diameter of 2 cm and an outer diameter of 2.4 cm. The centers of the upper, middle, and bottom parts of the base 31 are located in a straight line and are tightly welded. The lower end of the base 31 is connected to a hollow tube 32, and the lower end of the hollow tube 32 is connected to a porous tube 34. The porous tube 34 has through holes distributed on its wall. The lower end of the porous tube 34 is connected to a drill bit 35. The hollow tube 32 has a suction chamber 33 inside. In this embodiment, the suction chamber 33 has a hollow cylindrical structure. The lower end of the suction chamber 33 is connected to the upper end of the porous tube 34. The upper end of the suction chamber 33 is connected to a gas guide pipe 36. One end of the gas guide pipe 36 is connected to the suction chamber 33, and the other end extends out of the hollow tube 32 and is connected to a triangular valve 37. The hollow tube 32 has graduation lines 38 marked on its wall, with each graduation line 38 marking every 10 cm. To collect gas, open the triangular valve 37 and use the suction syringe to collect the gas.

[0038] Specifically, the different depths of the gas well components 3 are mainly achieved by the different depths of the hollow tube 32, that is, the depth of the hollow tube 32 determines the depth of the gas well components 3. In this embodiment, the depth of one set of gas well components 3 is 10cm, and the depth of the other set of gas well components 3 is 30cm. The depth of the shallow breathing ring 1 is 10cm, and the depth of the deep breathing ring 2 is 30-100cm.

[0039] Example 2 of a soil carbon flux monitoring device

[0040] As attached Figure 3 and attached Figure 1The soil carbon flux monitoring device shown differs from the previous embodiment in that the shallow breathing ring 1 is embedded with three sets of gas well components 3 at different depths, and the deep breathing ring 2 is embedded with the same three sets of gas well components 3 as the shallow breathing ring 1. The depth of the first set of gas well components 3 is 0-10cm, the depth of the second set of gas well components 3 is 10-30cm, and the depth of the third set of gas well components 3 is 30-60cm.

[0041] In this embodiment, the depth of the first group of gas well components 3 is 10cm, the depth of the second group of gas well components 3 is 30cm, the depth of the third group of gas well components 3 is 60cm, the depth of the shallow breathing ring 1 is 10cm, and the depth of the deep breathing ring 2 is 60-100cm.

[0042] The specific structure of gas well component 3 is the same as that in Embodiment 1, and will not be described further.

[0043] Example 3 of a soil carbon flux monitoring device

[0044] As attached Figure 4 and attached Figure 1 The soil carbon flux monitoring device shown differs from the previous embodiment in that the shallow breathing ring 1 is embedded with four sets of gas well components 3 at different depths, and the deep breathing ring 2 is embedded with the same four sets of gas well components 3 as the shallow breathing ring 1. The depth of the first set of gas well components 3 is 0-10cm, the depth of the second set of gas well components 3 is 10-30cm, the depth of the third set of gas well components 3 is 30-60cm, and the depth of the fourth set of gas well components 3 is 60-100cm.

[0045] In this embodiment, the depth of the first group of gas well components 3 is 10cm, the depth of the second group of gas well components 3 is 30cm, the depth of the third group of gas well components 3 is 60cm, the depth of the fourth group of gas well components 3 is 100cm, the depth of the shallow breathing ring 1 is 10cm, and the depth of the deep breathing ring 2 is 100cm.

[0046] The specific structure of gas well component 3 is the same as that in Embodiment 1, and will not be described further.

[0047] Example 1 of the full-section heating test device

[0048] refer to Figure 5 , Figure 8 , Figure 1 and Figure 2 A whole-soil profile warming test device includes a future climate simulation device and a current climate simulation device; the current climate simulation device includes a current climate shell 8, and the future climate simulation device includes a future climate shell 4, both of which are annular structures; both the future climate shell 4 and the current climate shell 8 are equipped with attachments. Figure 2 The soil carbon flux monitoring device shown has a heating mechanism and a temperature sensor 91 inside the future climate shell 4. The heating mechanism and the temperature sensor 91 are electrically connected to the temperature controller 7, which is an intelligent temperature controller SDM-CVO4.

[0049] The heating mechanism includes an annular heating coil 5 and multiple heating rods 6. The heating coil 5 is located inside the future climate housing 4 and is concentrically arranged with the future climate housing 4. The heating rods 6 are evenly distributed along the outer periphery of the future climate housing 4 and extend along the depth direction of the future climate housing 4. Humidity sensors 92 are installed inside both the future climate housing 4 and the current climate housing 8. The heating rods 6 can be cable rods, and the heating coil 5 is an annular heating cable coil.

[0050] In this embodiment, Figure 2 The total respiratory carbon flux monitoring device and the heterotrophic respiratory carbon flux monitoring device are nested within the future climate shell 4 and the current climate shell 8 of the whole-soil profile warming test device. Both the future climate shell 4 and the current climate shell 8 are annular rings with a diameter of 350 cm and a height of 30-100 cm. The central area with a diameter of 300 cm is the warming zone, and the 25 cm wide annular area near the heating rods 6 is the buffer zone. Twenty heating rods 6 are vertically embedded at equal intervals on the future climate shell 4. The length of the heating rods 6 is the same as the height of the future climate shell 4 and the current climate shell 8 to achieve uniform heating of the soil layer. A heating ring 5 is laid at radii of 50 cm and 100 cm on the inner perimeter to compensate for heat loss caused by cold air from the surface. No heating mechanism is set inside the current climate shell 8 to eliminate the interference of the device itself on the experimental results. The temperature difference of 4°C between the future climate shell 4 and the current climate shell 8 is controlled by a temperature controller SDM-CVO47 to simulate the magnitude of global warming at the end of this century.

[0051] Driven at a distance equidistant from the center of the future climate simulation device or the current climate simulation device Figure 2 The total respiratory carbon flux monitoring device and the heterotrophic respiratory carbon flux monitoring device were used. The shallow respiratory ring 1 and the deep respiratory ring 2 were spaced 10 cm apart, with 5 cm of each ring remaining above ground and the rest vertically buried in the soil. After the triangular valve 37 was closed and stabilized for a period of time, gas from wells at different depths was extracted using a suction syringe and introduced into a headspace vial. The carbon dioxide concentration was measured, and the soil profile carbon dioxide flux F was calculated using the Fick diffusion method. s (mol / m² / s), the total soil respiration flux is calculated within the shallow respiration loop 1, while the carbon dioxide flux calculated within the deep respiration loop 2 is the heterotrophic respiration flux dominated by microorganisms. The difference between the two is the autotrophic respiration flux dominated by roots. The specific flux calculation process is as follows:

[0052] Calculate carbon dioxide flux at soil profiles at various depths using Fick's diffusion law:

[0053] ;

[0054] In the formula, Ds is the effective diffusion coefficient of CO2 in the soil. 2 / s; △C(z) represents the change in soil CO2 concentration at a vertical depth of z meters, in μmol / m 3 Δ(z) represents the depth change in m; Ds is calculated using the following formula:

[0055] ;

[0056] In the formula, ε is the relative gas diffusion coefficient; D a The free atmospheric CO2 diffusion coefficient is T = 20℃ or 293.15K, P = 1.013 × 10⁻⁶. 5 When Pa, Da =1.47×10 -5 m 2 s -1 ε is calculated using the following formula:

[0057] ;

[0058] θ represents the soil volumetric water content (cm³). 3 / cm 3 ); For soil porosity, =ρ b / ρ m , ρ b Soil bulk density (g / cm³) 3 ;ρ m ρ represents the specific gravity of the soil, specifically for mineral soils. m =2.65 g / cm 3 .

[0059] Soil bulk density ρ b The soil bulk density was determined using the ring sampler method. Soil samples were collected at depths of 10 cm and 30 cm using a ring sampler, with three samples taken at each depth as replicates. The samples were dried at 105℃ for 24 hours until constant weight, and the soil bulk density ρ was calculated using the following formula. b :

[0060] ;

[0061] Where m is the soil mass after drying to constant weight, and v is the soil volume per 100 cm³. 3 The average soil bulk density at depths of 10 cm and 30 cm was taken.

[0062] Example 2 of the full-section heating test device

[0063] refer to Figure 6 , Figure 1 and Figure 3 A whole-soil profile warming test device includes a future climate simulation device and a current climate simulation device; the current climate simulation device includes a current climate shell 8, and the future climate simulation device includes a future climate shell 4, both of which are annular structures; both the future climate shell 4 and the current climate shell 8 are equipped with attachments. Figure 3 The soil carbon flux monitoring device shown is otherwise identical to the previous embodiment.

[0064] In this embodiment, Figure 3 The total respiratory carbon flux monitoring device and the heterotrophic respiratory carbon flux monitoring device are nested within the future climate shell 4 and the current climate shell 8 of the whole-soil profile warming test device. This warming test device consists of an intelligent temperature controller SDM-CVO47, cable rods 6, and heating coils 5. Both the future climate shell 4 and the current climate shell 8 are annular rings with a diameter of 350 cm and a height of 60-100 cm. The central area with a diameter of 300 cm is the warming zone, and the 25 cm wide annular area near the heating rods 6 serves as a buffer zone. Twenty heating rods 6 are vertically embedded at equal intervals around the circumference of the future climate shell 4, with the length of the heating rods 6 being the same as the height of both the future and current climate shells 8, to achieve uniform heating of the soil layer. Heating coils 5 are laid at radii of 50 cm and 100 cm on the inner perimeter to compensate for heat loss caused by cold air from the surface. No heating mechanism is installed inside the current climate shell 8 to eliminate interference from the device itself on the experimental results. The temperature difference of 4°C between the future climate shell 4 and the current climate shell 8 was controlled by the SDM-CVO47 temperature controller to simulate the magnitude of global warming at the end of this century.

[0065] Driven at a distance equidistant from the center of the future climate simulation device and the current climate simulation device Figure 3 The total respiratory carbon flux monitoring device and the heterotrophic respiratory carbon flux monitoring device were used. The shallow respiratory ring 1 and the deep respiratory ring 2 were spaced 10 cm apart, with 5 cm of each ring above ground and the rest buried vertically in the soil. After the triangular valve 37 was closed and stabilized for a period of time, gas from wells at different depths was extracted using a suction syringe and introduced into a headspace vial to measure the carbon dioxide concentration. The soil profile carbon dioxide flux Fs (mol / m² / s) was calculated using the Fick diffusion method. The total respiratory flux was calculated within the shallow respiratory ring 1, while the carbon dioxide flux calculated within the deep respiratory ring 2 was the heterotrophic respiratory flux dominated by microorganisms. The difference between the two was the autotrophic respiratory flux dominated by roots. The specific flux calculation process is as follows:

[0066] The carbon dioxide flux F at each soil profile depth was calculated using Fick's diffusion law. s :

[0067] ;

[0068] In the formula, Ds is the diffusion coefficient of CO2 in the soil. 2 / s; △C(z) represents the soil CO2 concentration (μmol / m³) at a vertical depth of z meters. 3 Δ(z) represents the depth change m; Ds is calculated using the following formula:

[0069] ;

[0070] In the formula, ε is the relative gas diffusion coefficient; D a The free atmospheric CO2 diffusion coefficient is T = 20℃ or 293.15K, P = 1.013 × 10⁻⁶. 5 When Pa, Da =1.47×10 -5 m 2 s -1 ε is calculated using the following formula:

[0071] ;

[0072] θ represents the soil volumetric water content (cm³). 3 / cm 3 ); For soil porosity, =ρ b / ρ m , ρ b Soil bulk density (g / cm³) 3 ;ρ m ρ represents the specific gravity of the soil, specifically for mineral soils. m =2.65 g / cm 3 .

[0073] Soil bulk density ρ b The soil bulk density was determined using the ring sampler method. Soil samples were collected at depths of 10 cm, 30 cm, and 60 cm using a ring sampler, with three samples taken at each depth as replicates. The samples were dried at 105℃ for 24 hours until constant weight, and the soil bulk density ρ was calculated using the following formula. b :

[0074] ;

[0075] Where m is the soil mass after drying to constant weight, and v is the soil volume per 100 cm³. 3 The average soil bulk density at depths of 10 cm, 30 cm, and 60 cm was taken.

[0076] Example 3 of the full-section heating test device

[0077] refer to Figure 7 , Figure 8 and Figure 4 A whole-soil profile warming test device includes a future climate simulation device and a current climate simulation device; the current climate simulation device includes a current climate shell 8, and the future climate simulation device includes a future climate shell 4, both of which are annular structures; both the future climate shell 4 and the current climate shell 8 are equipped with attachments. Figure 4 The soil carbon flux monitoring device shown has a heating mechanism and a temperature sensor 91 inside the future climate housing 4. The heating mechanism and temperature sensor 91 are electrically connected to a temperature controller 7, which is an intelligent temperature controller SDM-CVO4. The rest of the structure is the same as that in Embodiment 1.

[0078] In this embodiment, Figure 4 The total respiratory carbon flux monitoring device and the heterotrophic respiratory carbon flux monitoring device are nested within the future climate shell 4 and the current climate shell 8 of the whole-soil profile warming test device. Both the future climate shell 4 and the current climate shell 8 are annular rings with a diameter of 350 cm and a height of 100 cm. The central area with a diameter of 300 cm is the warming zone, and the 25 cm wide annular area near the heating rods 6 serves as a buffer zone. Twenty heating rods 6 are vertically embedded at equal intervals along the circumference of the future climate shell 4. The length of the heating rods 6 is the same as the height of both the future climate shell 4 and the current climate shell 8, achieving uniform heating of the soil layer. Heating rings 5 ​​are laid at radii of 50 cm and 100 cm on the inner perimeter to compensate for heat loss caused by cold air from the surface. No heating mechanism is installed inside the current climate shell 8 to eliminate interference from the device itself on the experimental results. The temperature difference of 4°C between the future climate shell 4 and the current climate shell 8 is controlled by a temperature controller SDM-CVO47 to simulate the magnitude of global warming at the end of this century.

[0079] Driven at a distance equidistant from the center of the future climate simulation device and the current climate simulation device Figure 4The total respiratory carbon flux monitoring device and the heterotrophic respiratory carbon flux monitoring device were used. The shallow respiratory ring 1 and the deep respiratory ring 2 were spaced 10 cm apart. The top 5 cm of the shallow respiratory ring 1 and the deep respiratory ring 2 were left above ground, and the rest were vertically buried in the soil. After the triangular valve 37 was closed and stabilized for a period of time, gas from wells at different depths was extracted using a suction needle and introduced into the headspace vial. The carbon dioxide concentration was measured, and the soil profile carbon dioxide flux Fs (mol / m² / s) was calculated using the Fick diffusion method. The total respiratory flux of the soil was calculated from the shallow respiratory ring 1, while the carbon dioxide flux calculated from the deep respiratory ring 2 was the heterotrophic respiratory flux dominated by microorganisms. The difference between the two was the autotrophic respiratory flux dominated by roots. The specific flux calculation process is as follows:

[0080] Calculate carbon dioxide flux at soil profiles at various depths using Fick's diffusion law:

[0081] ;

[0082] In the formula, Ds is the diffusion coefficient of CO2 in the soil (m). 2 / s); △C(z) is the soil CO2 concentration (μmol / m²) at a vertical depth of z meters. 3 ); Δ(z) is the depth change m; Ds is calculated using the following formula:

[0083] ;

[0084] In the formula, ε is the relative gas diffusion coefficient; D a The free atmospheric CO2 diffusion coefficient (T = 20℃ or 293.15K, P = 1.013×10⁻⁶) 5 When Pa, Da =1.47×10 -5 m 2 s -1 ε is calculated using the following formula:

[0085] ;

[0086] θ represents the soil volumetric water content (cm³). 3 / cm 3 ); For soil porosity, ( =ρ b / ρ m , ρ b Soil bulk density (g / cm³) 3 ); ρ m ρ represents the specific gravity of the soil, specifically for mineral soils. m =2.65 g / cm 3 .

[0087] Soil bulk density (ρ) b The soil bulk density was determined using the ring sampler method. Soil samples were collected at depths of 10 cm, 30 cm, 60 cm, and 100 cm using a ring sampler. Three samples were taken at each depth as replicates. The samples were dried at 105℃ for 24 hours to constant weight. The soil bulk density was calculated using the following formula:

[0088] ;

[0089] Where m is the soil mass after drying to constant weight, and v is the soil volume (in 100 cm³). 3 The average soil bulk density at each depth (10 cm, 30 cm, 60 cm, 100 cm) is taken.

[0090] A multi-depth gas well assembly (10 cm, 30 cm, 60 cm, and 100 cm deep) was combined with shallow breathing ring 1 and deep breathing ring 2. Through the precise stratified design of shallow breathing ring 1 and deep breathing ring 2, a three-dimensional analysis system of total soil respiration, heterotrophic respiration (microorganism-dominated), and autotrophic respiration (root-dominated) was constructed for different soil layers (0-10 cm, 10-30 cm, 30-60 cm, and 60-100 cm). This system enables the refined separation and quantitative monitoring of carbon flux of each component in the 0-100 cm soil profile.

[0091] In addition, by combining multi-depth gas well combination devices with intelligent temperature control devices, soil profile warming is carried out under natural conditions. An integrated system of "stratified monitoring-profile temperature control-dynamic response" for soil profile carbon flux assessment is constructed to explore the impact of future and current climate on the vertical stratification of soil profile carbon flux under natural conditions and to track the dynamic response characteristics of each soil layer and different types of carbon flux to warming in real time.

[0092] This solution addresses global warming and achieves its goals through technological innovation:

[0093] Precise stratified monitoring: Utilizing 10cm / 100cm dual-ring and multi-depth gas wells, the total respiration, heterotrophic respiration (microorganism-dominated), and autotrophic respiration (root-dominated) fluxes of each soil layer (0-100cm) are calculated separately, breaking through the limitations of traditional methods that focus on surface carbon flux and single carbon flux components.

[0094] Uniform heating across the entire profile: By burying cable rods and adding heating coils to the soil surface, temperature control with a difference of ±0.5℃ is achieved in the 0-100cm soil layer, simulating a 4℃ temperature increase scenario, solving the problems of traditional technology that can only simulate surface heating and that deep soil temperature is difficult to be heated synchronously.

[0095] Scientific value: It provides stratified data of the entire soil profile, corrects errors in carbon budget models, and reveals the lag effect of deep soil carbon pools; it quantifies the response of respiration components in each soil layer to climate warming, and helps to elucidate carbon feedback mechanisms.

[0096] High efficiency and adaptability: Standardized processes improve data repeatability, and modular components are adaptable to various soil types and ecosystems, providing a feasible and efficient path for quantifying the carbon flux components in different soil layers.

[0097] Figure 9 This study demonstrates the response of carbon dioxide flux at different soil depths to warming. Based on the "Loess Plateau Whole-Soil Profile Warming Experiment Platform," this scheme was used to explore the response characteristics of carbon dioxide flux at different soil depths to climate warming. The study found that the carbon dioxide flux in the 60-100 cm soil layer was significantly lower than that in other soil layers by more than 50%. Figure 9 A). Climate warming has significantly increased soil carbon dioxide flux by nearly 50% ( Figure 9 B). Climate warming has a particularly significant effect on increasing soil carbon dioxide flux in the 10-30 cm and 30-60 cm soil layers. Figure 9 C).

[0098] The results of this experiment demonstrate the significant feasibility of this proposed scheme at the technical implementation level. Further research data reveals that soil carbon dioxide flux exhibits significant vertical differentiation characteristics at different soil depths, highlighting the scientific and applied value of studying the response characteristics of stratified soil carbon dioxide flux and its environmental driving mechanisms.

[0099] The preferred embodiments of the present invention have been described above. It should be understood that those skilled in the art can make numerous modifications and variations based on the concept of the present invention without creative effort. Therefore, all technical solutions that can be obtained by those skilled in the art based on the concept of the present invention through logical analysis, reasoning, or limited experimentation on the basis of existing technology should be within the scope of protection defined by the claims.

Claims

1. A soil carbon flux monitoring device, characterized by: Including total respiratory carbon flux monitoring devices and heterotrophic respiratory carbon flux monitoring devices; The total respiratory carbon flux monitoring device includes a shallow respiratory ring (1), which is embedded with at least two sets of gas well components (3) at different depths. The depth of the shallow respiratory ring (1) is 5-10 cm. The heterotrophic respiratory carbon flux monitoring device includes a deep respiratory ring (2), which is embedded with the same gas well components (3) as the shallow respiratory ring (1). The depth of the deep respiratory ring (2) is 20-100 cm.

2. The soil carbon flux monitoring device of claim 1, wherein: The gas well assembly (3) includes a base (31), the lower end of which is connected to a hollow tube (32). The lower end of the hollow tube (32) is connected to a porous tube (34). The porous tube (34) has through holes distributed on its wall. The lower end of the porous tube (34) is connected to a drill bit (35). The hollow tube (32) is provided with a suction chamber (33). The lower end of the suction chamber (33) is connected to the upper end of the porous tube (34). The upper end of the suction chamber (33) is connected to a gas guide pipe (36). One end of the gas guide pipe (36) is connected to the suction chamber (33), and the other end extends out of the hollow tube (32) and is connected to a triangular valve (37).

3. The soil carbon flux monitoring device of claim 2, wherein: The hollow tube (32) has scale lines (38) marked on its tube wall.

4. A soil carbon flux monitoring device according to claim 2, characterized in that: The air extraction chamber (33) has a hollow columnar structure.

5. The soil carbon flux monitoring device of claim 1, wherein: The shallow breathing ring (1) is embedded with three sets of gas well components (3) at different depths. The deep breathing ring (2) is embedded with the same three sets of gas well components (3) as the shallow breathing ring (1). The depth of the first set of gas well components (3) is 0-10cm, the depth of the second set of gas well components (3) is 10-30cm, and the depth of the third set of gas well components (3) is 30-60cm.

6. The soil carbon flux monitoring device of claim 1, wherein: The shallow breathing ring (1) is embedded with four sets of gas well components (3) at different depths. The deep breathing ring (2) is embedded with the same four sets of gas well components (3) as the shallow breathing ring (1). The depth of the first set of gas well components (3) is 0-10cm, the depth of the second set of gas well components (3) is 10-30cm, the depth of the third set of gas well components (3) is 30-60cm, and the depth of the fourth set of gas well components (3) is 60-100cm.

7. A full profile warming test apparatus, characterized by: Including future climate simulation devices and current climate simulation devices; The current climate simulation device includes a current climate shell (8), and the future climate simulation device includes a future climate shell (4). Both the future climate shell (4) and the current climate shell (8) are equipped with a soil carbon flux monitoring device according to any one of claims 1-6. The future climate shell (4) is equipped with a heating mechanism and a temperature sensor (91), which are electrically connected to a temperature controller (7).

8. A full profile temperature rise test device according to claim 7, characterised in that: Both the future climate shell (4) and the current climate shell (8) have a ring-shaped structure; The heating mechanism includes an annular heating ring (5) and multiple heating rods (6). The heating ring (5) is located inside the future climate shell (4) and is concentrically arranged with the future climate shell (4). The heating rods (6) are evenly distributed along the outer periphery of the future climate shell (4) and extend along the depth direction of the future climate shell (4).

9. A full profile temperature rise test device according to claim 8, characterised in that: Humidity sensors (92) are provided inside both the future climate shell (4) and the current climate shell (8).

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