A frozen soil microorganism carbon sequestration monitoring device and method

Abstract

The application discloses a frozen soil microorganism carbon fixation monitoring device and method in the field of microorganism detection, which comprises a sunken base, a tent cloth and a sample gas collection interface, the base is half-buried in the soil surface, the tent cloth is in the shape of a tent and is sealingly connected with the base to define a gas chamber, the tent cloth is composed of an airtight inner layer and a waterproof outer layer, a memory metal wire cage is arranged in the interlayer, the device automatically balances air pressure during multiple sampling by using the flexible deformation of the tent cloth, and a pressure balance pipe is not needed, the method comprises the following steps: rapidly embedding the base into frozen soil by hammering, eliminating the bottom gap by melting wax, automatically forming and building the chamber by using the memory metal, and sampling and calculating the flux. The application solves the problems of the traditional rigid box, such as difficult transportation and deployment in the frozen soil area and distorted data caused by negative pressure during sampling, and has the characteristics of portability and fast deployment.

Description

Technical Field

[0001] This invention relates to the field of microbial detection, and specifically to a device and method for monitoring carbon sequestration by microorganisms in permafrost. Background Technology

[0002] Currently, monitoring of microbial carbon sequestration and release fluxes in permafrost ecosystems mainly relies on the static box method or eddy covariance technique. Among these, the static box method has become a commonly used tool for measuring small-scale gas exchange at the soil-atmosphere interface due to its relatively low cost and flexible deployment. However, existing static box monitoring devices have significant technical problems, especially in the harsh environment of permafrost regions.

[0003] Traditional static monitoring systems are used in remote monitoring sites with poor transportation, such as those in the Arctic and high-altitude permafrost regions. Due to transportation efficiency limitations, the number and scope of monitoring sites are greatly restricted.

[0004] In addition, when existing rigid static chambers perform multiple gas samplings, the gas accumulated inside the chamber gradually forms a negative pressure when it is drawn out by the syringe. This negative pressure draws in external air through the tiny gaps at the connection between the chamber and the base, diluting the concentration of the target gas inside the chamber and causing the flux data to be underestimated or distorted.

[0005] To solve the negative pressure problem, traditional rigid static chambers must rely on additional pressure balancing pipes (such as thin pipes with liquid seals) to balance the air pressure inside and outside the chamber. However, these balancing pipes are prone to liquid freezing, blockage, or structural damage in cold environments, affecting the reliability and airtightness of the system. Summary of the Invention

[0006] The purpose of this invention is to provide a device and method for monitoring carbon sequestration by microorganisms in permafrost, in order to solve the problems of difficulty in transporting and deploying existing rigid static boxes in harsh permafrost environments and the data distortion caused by negative pressure during the sampling process.

[0007] To solve the above-mentioned technical problems, the present invention specifically provides the following technical solution:

[0008] A permafrost microbial carbon sequestration monitoring device includes:

[0009] The recessed base is configured to be partially buried below the soil surface, and through holes are formed on the recessed base to expose the soil surface.

[0010] The tarpaulin is tent-shaped. The bottom of the tarpaulin is sealed to the part of the embedded base that protrudes above the soil surface. The tarpaulin and the embedded base together define a gas chamber above the soil surface.

[0011] The sample gas collection interface is located on the tarpaulin;

[0012] The tarpaulin is composed of an airtight inner layer and a waterproof outer layer. The airtight inner layer is used to ensure the airtightness of the gas chamber.

[0013] A memory metal wire cage frame is installed in the interlayer between the airtight inner layer and the waterproof outer layer to keep the tarpaulin in the shape of a tent;

[0014] The tarpaulin can balance the pressure changes through its flexible deformation while the gas chamber is being sampled multiple times.

[0015] Furthermore, the bottom edge of the tarpaulin is detachably connected to the upper wall of the through hole via a first zipper. The male strap of the first zipper is fixedly arranged in a ring on the inner wall of the through hole, and the female strap of the first zipper is fixedly connected in a ring to the bottom edge of the tarpaulin.

[0016] A plastic sealant is provided on the outside of the first zipper to seal its seams.

[0017] Furthermore, a ring of eaves tape is fixed to the outer side of the lower edge of the waterproof outer layer of the tarpaulin. The eaves tape is detachably connected to the outer wall of the recessed base by a second zipper. The male strap of the second zipper is fixedly set in a ring on the outer wall of the recessed base, and the female strap of the second zipper is fixedly connected in a ring to the bottom edge of the eaves tape.

[0018] The first zipper, the second zipper, the recessed base, and the tarpaulin together define an annular sealing groove for containing sealing mud. The annular sealing groove is located on the outside of the joint of the first zipper.

[0019] Furthermore, the recessed base is a pre-embedded base, and the through hole is located at the center of the pre-embedded base.

[0020] Furthermore, the recessed base is circular in shape, and its inner hole forms a through hole, and the annular bottom edge of the recessed base forms a ring of downward-facing serrations.

[0021] Several hammering parts are fixedly connected to the outer cylindrical wall of the recessed base, which are evenly distributed along its circumference. The hammering parts are nail-shaped, with the sharp lower end of the hammering part lower than the lower edge of the recessed base, and the upper end of the hammering part higher than the upper edge of the recessed base. The upper end of the hammering part forms a planar force-bearing part for bearing the hammering force.

[0022] When the planar force-bearing part is subjected to external force, it causes the corresponding part of the sinking base that is fixed to it to sink downward into the soil surface.

[0023] Furthermore, the memory metal wire cage frame includes several sets of warp support wires and several weft constraint wires. The warp support wires extend from the top to the bottom edge along the height direction of the tarpaulin. All the warp support wires are evenly arranged around the circumference of the tarpaulin. The weft constraint wires are arranged in a circumferential ring and are distributed at intervals along the height direction of the tarpaulin. Each weft constraint is fixedly connected to the warp support wire.

[0024] Furthermore, the sample gas collection interface consists of a rigid mounting base and a self-sealing sampling plug;

[0025] The rigid mounting base is airtightly fixed to the tarpaulin and has a fitting hole formed in its center;

[0026] The self-sealing sampling plug is embedded in the fitting hole, and the outer periphery of the self-sealing sampling plug is airtightly connected to the inner wall of the fitting hole.

[0027] A temperature sensor is installed on the rigid mounting base to detect the temperature inside the gas chamber.

[0028] Furthermore, an aluminized polyester film with high gas barrier properties is formed on the inner wall of the airtight inner layer.

[0029] Furthermore, the recessed base is coated with a ring of sealing wax at the junction of its inner and outer walls and the soil surface.

[0030] A method for monitoring microbial carbon sequestration in permafrost, comprising the following steps:

[0031] S1. On-site deployment of the equipment:

[0032] S1.1 Utilize the flat force-bearing part on the sinking base to withstand the hammering force, thereby driving the sawtooth-shaped annular bottom edge of the sinking base to be embedded downward into the soil surface to a predetermined depth.

[0033] S1.2 Eliminate the gap at the junction of the base and the soil surface by cladding with sealing wax;

[0034] S2. Chamber construction and sealing:

[0035] S2.1 Unfold the tarpaulin from its folded state, allowing its built-in memory metal wire cage frame to automatically form and support the tarpaulin in the predetermined tent shape;

[0036] S2.2 The bottom edge of the tarpaulin is detachably connected to the recessed base via the first zipper;

[0037] S2.3. A plastic sealant is applied to the outside of the first zipper to achieve an airtight seal of the gas chamber.

[0038] S3. Gas flux acquisition and balance:

[0039] Within a predetermined time interval, gas samples are repeatedly extracted from the gas chamber using a needle through the sample gas collection interface, and the time and temperature of each extraction are recorded. The tarpaulin balances the pressure changes inside and outside the chamber in real time during the multiple sampling processes through its own flexible deformation.

[0040] S4. Flux Calculation and Monitoring:

[0041] The collected gas samples were subjected to chromatographic analysis to obtain the concentration change rate of carbon dioxide (CO2) and methane (CH4) in the gas samples. Based on the concentration change rate and structural parameters such as the perforation area of ​​the embedded base and the height of the tarpaulin, the net carbon gas exchange flux of the frozen soil was calculated to evaluate the carbon fixation / release rate of frozen soil microorganisms.

[0042] The beneficial effects of this invention are:

[0043] This invention constructs a gas chamber using a flexible tarpaulin composed of an airtight inner layer and a waterproof outer layer, combined with a memory metal wire cage frame. The memory metal wire cage frame provides support, allowing the flexible tarpaulin to overcome its own weight and maintain a predetermined tent shape. This helps to balance the pressure difference between the inside and outside of the chamber after the sample gas is extracted, while also ensuring the device's foldability and portability. This solves the technical problem of transporting and deploying rigid containers in remote permafrost areas. Attached Figure Description

[0044] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are merely exemplary, and those skilled in the art can derive other embodiments based on the provided drawings without creative effort.

[0045] Figure 1 This is a schematic diagram of the planar structure of an embodiment of the present invention;

[0046] Figure 2 This is a front view of a memory metal wire cage frame according to an embodiment of the present invention;

[0047] Figure 3 This is a top view of the memory metal wire cage frame according to an embodiment of the present invention;

[0048] Figure 4 This is a schematic diagram showing the connection state between the lower edge of the tarpaulin and the recessed base in an embodiment of the present invention.

[0049] Figure 5 This is a planar structural cross-sectional view of the sample gas collection mechanism according to an embodiment of the present invention;

[0050] The labels in the diagram represent the following:

[0051] 1-Embedded base; 1a-Through hole; 1b-Serpentine; 1c-Hammering part; 1d-Plane stress-bearing part; 2-Tannel; 2a-Airtight inner layer; 2b-Waterproof outer layer; 2c-Eaves tape; 2d-Annular sealing groove; 2e-Memory metal wire cage frame; 2f-Warp support wire; 2g-Weft constraint wire; 3-Sample gas collection interface; 3a-Rigid mounting base; 3b-Matching hole; 3c-Self-sealing sampling plug; 3d-Sealing ring; 4-First zipper; 5-Plastic sealant; 6-Second zipper; 7-Sealing wax; 8-Temperature sensor. Detailed Implementation

[0052] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0053] This embodiment provides a permafrost microbial carbon sequestration monitoring device, aiming to solve the problems of existing rigid static boxes being difficult to deploy and transport in harsh permafrost environments, and data distortion caused by negative pressure during sampling. Specifically, refer to... Figures 1 to 5 The permafrost microbial carbon fixation monitoring device includes an embedded base 1, a tarpaulin 2, and a sample gas collection interface 3.

[0054] The embedded base 1 is configured to be partially buried below the soil surface, and the embedded base 1 has through holes 1a formed on it to expose the soil surface so that the soil can exchange gases with the space above.

[0055] The tarpaulin 2 is shaped like a tent. The bottom of the tarpaulin 2 is sealed to the part of the embedded base 1 that is exposed on the soil surface. The tarpaulin 2 and the embedded base 1 together define a gas chamber on the soil surface. The gas sampling interface 3 is set on the tarpaulin 2 for extracting gas samples.

[0056] To balance portability and airtightness, the tarpaulin 2 is composed of an airtight inner layer 2a and a waterproof outer layer 2b. The airtight inner layer 2a is used to ensure the airtightness of the gas chamber and prevent external air from penetrating. In the interlayer between the airtight inner layer 2a and the waterproof outer layer 2b, a memory metal wire cage frame 2e is provided to keep the tarpaulin 2 in the shape of a tent.

[0057] The core advantage of the above-mentioned basic scheme is that, compared with the traditional rigid box, this device utilizes the flexible characteristics of the tarpaulin 2. When multiple samplings are performed through the sample gas collection interface 3, resulting in a reduction of gas in the gas chamber, the tarpaulin 2 can balance the gas pressure change by its own flexible deformation (e.g., slightly shrinking inward) while the gas chamber is being sampled multiple times.

[0058] This adaptive volume adjustment mechanism eliminates the pressure difference between the inside and outside of the chamber, thus eliminating the need to rely on traditional pressure balancing tubes. This avoids the risk of the balancing fluid freezing or the pipeline becoming blocked in cold environments, ensuring that external air is not drawn in due to negative pressure during multiple sampling processes, and guaranteeing the accuracy of the monitoring data.

[0059] Regarding the specific form of the embedded base 1, in some long-term fixed monitoring scenarios, the embedded base 1 can be designed as a pre-embedded base, with the through hole 1a located at the center of the pre-embedded base. This structure is suitable for situations where excavation and installation can be carried out in advance during the non-freezing period. However, in hard surfaces such as the Arctic or high-altitude permafrost where excavation is difficult, or in scenarios requiring rapid deployment, the installation of traditional pre-embedded bases is extremely time-consuming and damages the soil structure.

[0060] To solve this problem, this embodiment improves the embedding base 1. The improved embedding base 1 is annular in shape, and its inner hole forms a through hole 1a. The annular bottom edge of the embedding base 1 forms a ring of downward-facing serrations 1b. At the same time, several hammering parts 1c are fixedly connected to the outer cylindrical wall of the embedding base 1 and are evenly distributed around its circumference. The hammering parts 1c are nail-shaped and are fixedly welded to the outer wall of the embedding base 1 by a welding piece. The sharp lower end of the hammering part 1c is lower than the lower edge of the embedding base 1, and the upper end of the hammering part 1c is higher than the upper edge of the embedding base 1. Furthermore, a planar force-bearing part 1d for bearing the hammering force is formed at the upper end of the hammering part 1c.

[0061] During installation, to ensure that the embedded base 1 can be vertically and stably embedded into the soil surface, and to avoid the base tilting or the opposite side lifting due to excessive force on one side, a diagonal alternating hammering method must be adopted. Specifically, the operator hammers the two oppositely arranged hammering parts 1c in the diagonal direction of the embedded base 1 in turn, and repeats this process to complete the hammering operation of all hammering parts 1c in one revolution.

[0062] During the alternating external force impact on the planar force-bearing part 1d, the embedded base 1, which is fixed to it, moves downwards evenly until the bottom edge of the serrated 1b is embedded into the soil surface to a predetermined depth. The serrated 1b structure can effectively cut into hard frozen soil or plant roots. The aforementioned diagonal alternating force application method ensures the stability of the base during the soil breaking process, realizing rapid and rigid deployment under harsh geological conditions.

[0063] Although the sawtooth 1b and hammering structure enable rapid embedding, tiny gaps that are difficult to detect with the naked eye may still exist at the contact surface between the base wall and the uneven soil surface, which can affect air tightness. To further improve the sealing effect, a ring of sealing wax 7 is melted and coated at the junction of the inner and outer walls of the embedded base 1 with the soil surface. The sealing wax 7 has excellent fluidity in the molten state, which can fill all the micro-gaps between the base and the soil. After solidification, it forms a reliable physical barrier, completely eliminating the hidden danger of air leakage at the bottom.

[0064] After solving the base deployment problem, another key point is how to quickly and airtightly connect the flexible tarpaulin 2 to the rigid recessed base 1. Direct physical buckles or bindings are difficult to guarantee airtightness. Therefore, this embodiment adopts a layered connection and sealing structure. The bottom edge of the tarpaulin 2 and the upper wall of the through hole 1a are detachably connected by a first zipper 4. The male strap of the first zipper 4 is fixedly set in a ring (preferably glued) to the inner wall of the through hole 1a, and the female strap of the first zipper 4 is fixedly connected to the bottom edge of the tarpaulin 2 in a ring.

[0065] The main function of the first zipper 4 is to achieve rapid mechanical positioning and initial connection between the tarpaulin 2 and the base. Considering that there are gaps between the zipper teeth, it is impossible to achieve the airtightness of the gas analysis level. Therefore, a plastic sealant 5 (such as sealing mud) is provided on the outside of the first zipper 4 to seal its seam.

[0066] Furthermore, simply applying sealant can easily cause it to peel off or deform under external pressure in outdoor environments, leading to seal failure. To provide a stable adhesion and protective space for the sealant, this embodiment constructs a second connecting structure on the outside of the first zipper 4. A ring of eaves tape 2c is fixed to the outer side of the lower edge of the waterproof outer layer 2b of the tarpaulin 2. The eaves tape 2c is detachably connected to the outer wall of the recessed base 1 via a second zipper 6.

[0067] Specifically, the male strap of the second zipper 6 is fixedly arranged in a ring (preferably glued) on the outer wall of the recessed base 1, and the female strap of the second zipper 6 is fixedly connected in a ring to the bottom edge of the eaves fabric 2c. Through this design, the first zipper 4, the second zipper 6, the recessed base 1 and the tarpaulin 2 together define an annular sealing groove 2d for accommodating sealing mud, and the annular sealing groove 2d is located on the outside of the joint of the first zipper 4.

[0068] The annular sealing groove 2d can tightly wrap the plastic sealant 5, which not only prevents the sealant from leaking out, but also forces the sealant to fill the gap of the first zipper 4 through the binding force of the second zipper 6, thus achieving a double-protection sealing effect.

[0069] Regarding the support structure of the tarpaulin 2, in order to ensure that the tarpaulin 2 can maintain a relatively stable geometric shape under the interference of external factors such as wind, so as to ensure the accuracy of the sampling volume estimation, the memory metal wire cage 2e includes several sets of warp support wires 2f and several weft constraint wires 2g. The warp support wires 2f extend from the top to the bottom edge along the height direction of the tarpaulin 2. All the warp support wires 2f are evenly arranged around the tarpaulin 2 in the circumference, mainly used to provide support force in the height direction. The weft constraint wires 2g are arranged in a circumferential ring and are distributed at intervals along the height direction of the tarpaulin 2. Each weft constraint is fixedly connected to the warp support wire 2f.

[0070] This interwoven cage structure ensures that the tarpaulin 2 has the ability to deform flexibly to balance the air pressure, while limiting its excessive collapse or twisting, thus ensuring the stability of the gas chamber shape.

[0071] Regarding the material selection for the airtight inner layer 2a, ordinary polymer films may not be able to completely block small molecule gases such as carbon dioxide or methane. Therefore, in this embodiment, an aluminized polyester film with high gas barrier properties is formed on the inner wall of the airtight inner layer 2a. The aluminized polyester film has extremely low gas permeability, which ensures that during long-term monitoring periods, changes in the target gas concentration in the chamber are caused only by soil biological activity, rather than by errors caused by material permeation.

[0072] For the sample gas collection interface 3, since the tarpaulin 2 itself is a flexible fabric, it cannot directly withstand repeated punctures from the syringe needle, and the puncture holes are difficult to heal themselves. Therefore, the sample gas collection interface 3 consists of a rigid mounting base 3a and a self-sealing sampling plug 3c. The rigid mounting base 3a is airtightly fixed to the tarpaulin 2 by a sealing ring 3d, and a fitting hole 3b is formed in its center, providing stable mechanical support for the sampling operation.

[0073] The self-sealing sampling plug 3c (e.g., a sample septum, which is a standard part and has the characteristic of automatically closing the hole by elastic retraction after being punctured) is embedded in the fitting hole 3b, and the outer periphery of the self-sealing sampling plug 3c is airtightly connected to the inner wall of the fitting hole 3b.

[0074] In addition, considering the high sensitivity of gas flux calculation to temperature parameters, a temperature sensor 8 is also provided on the rigid mounting base 3a to detect the temperature inside the gas chamber, so as to obtain environmental parameters in real time during sampling.

[0075] Based on the above-described device, this embodiment also provides a method for monitoring microbial carbon fixation in permafrost using the device. This method fully utilizes the structural features of the device and includes the following steps:

[0076] S1. On-site deployment of the equipment:

[0077] S1.1. The planar force-bearing part 1d on the sinking base 1 bears the hammering force, which drives the sawtooth 1b-shaped annular bottom edge of the sinking base 1 to be embedded downward into the soil surface to a predetermined depth. This step uses the hammering part 1c and the sawtooth 1b to achieve rapid soil breaking and stable installation on hard frozen soil.

[0078] S1.2. The gap at the junction of the base and the soil surface is eliminated by cladding with sealing wax 7. This step ensures the absolute airtightness of the contact surface between the base and the ground surface.

[0079] S2. Chamber construction and sealing:

[0080] S2.1 Unfold the tarpaulin 2 from its folded state, so that its built-in memory metal wire cage 2e automatically forms and supports the tarpaulin 2 in the predetermined tent shape. This step utilizes the characteristics of memory metal to achieve tool-free rapid forming.

[0081] S2.2. The bottom edge of the tarpaulin 2 is detachably connected to the recessed base 1 via the first zipper 4 to achieve initial positioning;

[0082] S2.3. A plastic sealant 5 is placed on the outside of the first zipper 4 (i.e., inside the annular sealing groove 2d), and the second zipper 6 is pulled up to complete the airtight seal of the gas chamber.

[0083] S3. Gas flux collection and balancing: Within a predetermined time interval, gas samples are repeatedly drawn from the gas chamber through the sample gas collection interface 3 using a needle, and the time and temperature of each extraction are recorded. During this process, the tarpaulin 2 balances the gas pressure changes inside and outside the chamber in real time through its own flexible deformation during multiple sampling, and negative pressure can be avoided without manual intervention.

[0084] S4. Flux Calculation and Monitoring: The collected gas samples are subjected to chromatographic analysis to obtain the concentration change rate (dc / dt) of carbon dioxide (CO2) and methane (CH4) in the gas samples. Based on the concentration change rate and structural parameters such as the area of ​​the through hole 1a of the embedded base 1 and the height of the tarpaulin 2, the net carbon gas exchange flux of the frozen soil is calculated.

[0085] Specifically, although the tent has an irregular shape, its effective coverage area (A) is determined by the area of ​​the through-hole 1a of the recessed base 1, which is constant. The formula for calculating the gas flux (F) is usually expressed as: F = (dc / dt) x (M / V) m ) x (V / A). Where M is the molar mass of the gas, V mLet V be the gas molar volume (affected by temperature and corrected by sensor data), V be the chamber volume, and A be the covering area. In this method, although the tarpaulin 2 has slight deformation, an effective volume (V) can be estimated using a geometric formula based on the geometric height (H) of the tarpaulin 2 and the base area (A), or it can be calculated directly using the effective height (Heff = V / A). The final obtained net carbon gas exchange flux is used to evaluate the carbon fixation / release rate of permafrost microorganisms.

[0086] The above embodiments are merely exemplary embodiments of the present invention and are not intended to limit the present invention. The scope of protection of the present invention is defined by the claims. Those skilled in the art can make various modifications or equivalent substitutions to the present invention within its spirit and scope of protection, and such modifications or equivalent substitutions should also be considered as falling within the scope of protection of the embodiments of the present invention.

Claims

1. A permafrost microbial carbon sequestration monitoring device, characterized in that, include: A recessed base (1) is configured to be partially buried below the soil surface, and a through hole (1a) is formed on the recessed base (1) for exposing the soil surface. The tarpaulin (2) is in the shape of a tent. The bottom of the tarpaulin (2) is sealed to the part of the embedded base (1) that is exposed on the soil surface. The tarpaulin (2) and the embedded base (1) together define a gas chamber on the soil surface. The sample gas collection interface (3) is set on the tarpaulin (2); The tarpaulin (2) is composed of an airtight inner layer (2a) and a waterproof outer layer (2b), wherein the airtight inner layer (2a) is used to ensure the airtightness of the gas chamber; A memory metal wire cage frame (2e) is provided in the interlayer between the airtight inner layer (2a) and the waterproof outer layer (2b) to maintain the tarpaulin (2) in the shape of a tent. The tarpaulin (2) can balance the gas pressure change through its own flexible deformation while the gas chamber is sampled multiple times; the bottom edge of the tarpaulin (2) and the upper wall of the through hole (1a) are detachably connected by a first zipper (4), the male strap of the first zipper (4) is fixedly set in a ring on the inner wall of the through hole (1a), and the female strap of the first zipper (4) is fixedly connected in a ring to the bottom edge of the tarpaulin (2); A plastic sealant (5) for sealing the seam is provided on the outside of the first zipper (4); a ring of eaves tape (2c) is fixedly connected to the lower edge of the waterproof outer layer (2b) of the tarpaulin (2), and the eaves tape (2c) is detachably connected to the outer wall of the recessed base (1) by a second zipper (6). The male strap of the second zipper (6) is fixedly set in a ring on the outer wall of the recessed base (1), and the female strap of the second zipper (6) is fixedly connected in a ring to the bottom edge of the eaves tape (2c). The first zipper (4), the second zipper (6), the recessed base (1), and the tarpaulin (2) together define an annular sealing groove (2d) for accommodating sealing mud. The annular sealing groove (2d) is located on the outside of the seam of the first zipper (4). The recessed base (1) is annular, and its inner hole forms the through hole (1a). The annular bottom edge of the recessed base (1) has a ring of downward-facing serrations (1b). A plurality of hammering parts (1c) are fixedly connected to the outer cylindrical wall of the recessed base (1) and are evenly distributed along its circumference. The hammering parts (1c) are nail-shaped. The sharp lower end of the hammering part (1c) is lower than the lower edge of the recessed base (1), and the upper end of the hammering part (1c) is higher than the upper edge of the recessed base (1). Furthermore, a planar force-bearing part (1d) for bearing the hammering force is formed at the upper end of the hammering part (1c). During the process of being struck by external force, the planar force-bearing part (1d) drives the corresponding part of the sinking base (1) fixed to it to be embedded downward into the soil surface; the memory metal wire cage frame (2e) includes several sets of warp support wires (2f) and several weft constraint wires (2g). The warp support wires (2f) extend from the top to the bottom edge along the height direction of the tarpaulin (2). All the warp support wires (2f) are evenly arranged around the circumference of the tarpaulin (2). The weft constraint wires (2g) are arranged in a circumferential ring and are distributed at intervals along the height direction of the tarpaulin (2). Each weft constraint wire (2g) is fixedly connected to the warp support wire (2f).

2. The permafrost microbial carbon sequestration monitoring device according to claim 1, characterized in that, The recessed base (1) is a pre-embedded base, and the through hole (1a) is located at the center of the pre-embedded base.

3. The permafrost microbial carbon sequestration monitoring device according to claim 1, characterized in that, The sample gas collection interface (3) consists of a rigid mounting base (3a) and a self-sealing sampling plug (3c); The rigid mounting base (3a) is airtightly fixed to the tarpaulin (2) and has a fitting hole (3b) formed in its center. The self-sealing sampling plug (3c) is embedded in the fitting hole (3b), and the outer periphery of the self-sealing sampling plug (3c) is airtightly connected to the inner wall of the fitting hole (3b). A temperature sensor (8) for detecting the temperature inside the gas chamber is provided on the rigid mounting base (3a).

4. The permafrost microbial carbon sequestration monitoring device according to claim 1, characterized in that, An aluminized polyester film with high gas barrier properties is formed on the inner wall of the airtight inner layer (2a).

5. The permafrost microbial carbon sequestration monitoring device according to claim 1, characterized in that, The embedded base (1) has a ring of sealing wax (7) melted on its inner and outer walls at the junction with the soil surface.

6. A method for monitoring microbial carbon sequestration in permafrost based on the device described in claim 1, characterized in that, The method includes the following steps: S1. On-site deployment of the equipment: S1.

1. The planar force-bearing part (1d) on the sinking base (1) bears the hammering force, causing the sawtooth (1b) annular bottom edge of the sinking base (1) to be driven downward into the soil surface to a predetermined depth. S1.2, Eliminate the gap at the junction of the embedded base (1) and the soil surface by cladding with sealing wax (7); S2. Chamber construction and sealing: S2.1 Unfold the tarpaulin (2) from its folded state so that its built-in memory metal wire cage frame (2e) automatically forms and supports the tarpaulin (2) in a predetermined tent shape; S2.2, The bottom edge of the tarpaulin (2) is detachably connected to the recessed base (1) via the first zipper (4); S2.

3. A plastic sealant (5) is provided on the outside of the first zipper (4) to complete the airtight seal of the gas chamber; S3. Gas flux acquisition and balance: Within a predetermined time interval, the gas sample in the gas chamber is extracted multiple times using a needle through the sample gas collection interface (3), and the time and temperature of each extraction are recorded. The tarpaulin (2) balances the gas pressure changes inside and outside the chamber in real time during multiple sampling processes through its own flexible deformation. S4. Flux Calculation and Monitoring: The collected gas samples were subjected to chromatographic analysis to obtain the concentration change rate of carbon dioxide (CO2) and methane (CH4) in the gas samples. Based on the concentration change rate and the area of ​​the through hole (1a) of the embedded base (1) and the height of the tarpaulin (2), the net carbon gas exchange flux of the frozen soil was calculated to evaluate the carbon fixation / release rate of frozen soil microorganisms.

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