Measuring device suitable for depth of bumblebee hive in permafrost region of Qinghai-Tibet Plateau

Abstract

The invention relates to a device suitable for measuring the depth of a bumblebee honeycomb in a permafrost region of the Qinghai-Tibet Plateau. The device comprises a hollow cylindrical sensing carrier, a micro sensor array, a microcontroller and a micro-SD card, wherein the microcontroller and the micro-SD card are arranged in a ground surface IP67 protection box. The surface of the sensing carrier is provided with a diamond-like coating, the bottom is provided with an annular elastic supporting belt, and the top is provided with a quick-release lacing system along the circumferential direction; the annular elastic supporting belt is provided with a titanium alloy sawtooth ring. A micro sensor array consisting of a plurality of acoustic sensors and a plurality of temperature sensors is arranged on the surface of the diamond-like carbon coating; the surface of each acoustic sensor and the surface of each temperature sensor are provided with silicon nitride cover stickers. And the microcontroller is electrically connected with the micro-SD card, the plurality of acoustic sensors and the plurality of temperature sensors respectively. The method is efficient, the interference to the ecological environment is extremely small, and the obtained honeycomb depth data is a direct index for selecting the adaptability of the bee colony to the frozen soil environment.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of permafrost and ecological environment monitoring in the Qinghai-Tibet Plateau, and particularly relates to a measuring device for nest depth of bumblebees in the Qinghai-Tibet Plateau permafrost region. BACKGROUND

[0002] Wild bees are essential pollinators in terrestrial ecosystems, providing pollination services for over 75% of food crops and nearly 80% of wild flowering plants. The mutualistic relationship between plants and bees is not only a key link in plant sexual reproduction, but also a key to maintaining the diversity of natural ecosystems. However, the current global wild bee population and diversity is facing severe challenges, with the main driving factors including global climate warming, habitat loss, and overuse of pesticides. This declining trend will disrupt plant-pollinator networks, affect plant reproductive success and the long-term survival of their populations, and ultimately may trigger a cascade effect of biodiversity loss. Therefore, it is necessary to monitor bee habitat preferences (mainly nest depth) and responses to environmental changes from the source, in order to develop effective protection strategies and management measures.

[0003] The Qinghai-Tibet Plateau is a sensitive area and amplifier of global climate change, and its unique permafrost ecosystem plays an irreplaceable role in maintaining local regional and even larger-scale biodiversity. The species of wild bees in this region are relatively few, but their pollination services are closely related to the structure and function of fragile ecosystems such as alpine meadows and shrubs. Most flowering plants on the plateau are highly dependent on limited bees for pollination, and their reproductive success is often limited by the effectiveness of bee activity. It is worth noting that most bees in this region prefer to nest in loose soil 10-30 cm below the surface, which skillfully avoids the difficult-to-dig permafrost layer (perennial frozen layer), while taking advantage of the relatively stable buffer zone of temperature and humidity formed above the seasonal freezing layer. Therefore, the actual depth of the nest becomes a key indicator of the adaptability of the bee colony to the local microenvironment, and its changes can sensitively reflect the impact of permafrost degradation (such as the deepening of the active layer and the rise of ground temperature) on the living environment of bees.

[0004] However, the extreme environment of the plateau (low temperature, strong wind, lack of oxygen) and the heterogeneity of the permafrost layer make it difficult to overcome the serious challenges faced by traditional nest exploration methods that rely on physical excavation: low efficiency, easy measurement failure or serious distortion of nest depth data, difficulty in accurately reflecting the true position of the nest, and destructive and disruptive. Therefore, it is urgent to develop a non-invasive nest depth measuring device that is efficient, minimally disruptive to the ecological environment, and can adapt to the harsh environment of the plateau and the complexity of the permafrost. SUMMARY

[0005] The technical problem to be solved by the present application is to provide a measuring device for the depth of a bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau, which is efficient and has little disturbance to the ecological environment.

[0006] To solve the above problems, the measuring device for the depth of a bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau comprises a hollow cylindrical sensing carrier, a micro-sensor array, and a microcontroller and a micro-SD card in an IP67 protection box on the ground surface; the surface of the sensing carrier is provided with a diamond-like coating, the bottom is provided with an annular elastic support belt, and the top is provided with a quick-release lacing system in the circumferential direction; the annular elastic support belt is provided with a titanium alloy serrated ring; the surface of the diamond-like coating is provided with the micro-sensor array composed of a plurality of acoustic sensors and a plurality of temperature sensors; the surface of each acoustic sensor and each temperature sensor is provided with a silicon nitride envelope sticker; the microcontroller is electrically connected with the micro-SD card, the plurality of acoustic sensors, and the plurality of temperature sensors.

[0007] The outer diameter of the sensing carrier is 20 cm, the inner diameter is 18.8 cm, and the height is 40 cm.

[0008] The material of the quick-release lacing system is aramid fiber bundle, and the breaking strength is more than 3.5 kN.

[0009] The inner wall of the annular elastic support belt is embedded with a micro strain gauge made of metal foil or semiconductor material.

[0010] The serrated ring is made of titanium alloy, the tooth depth is 15 mm±0.2 mm, the tooth inclination angle is 45°±1°, and the tooth tip curvature radius R is 0.1 mm.

[0011] The plurality of acoustic sensors and the plurality of temperature sensors are unevenly arranged according to different layers and different intervals, and each layer is provided with the acoustic sensor and the temperature sensor.

[0012] The plurality of acoustic sensors and the plurality of temperature sensors are arranged according to layers of 0-10 cm, 10-30 cm, and 30-40 cm, and the interval between adjacent two sensors in the layer of 0-10 cm is 4.7 cm, the interval between adjacent two sensors in the layer of 10-30 cm is 3.1 cm, and the interval between adjacent two sensors in the layer of 30-40 cm is 9.4 cm.

[0013] The frequency range of the acoustic sensor is 0.022-22 kHz, and the gain is set to 40 dB.

[0014] The temperature resolution of the temperature sensor is 0.02℃.

[0015] A method for preparing a measuring device as described above, comprising the following steps: S1: a hollow cylinder with an outer diameter of 20 cm, an inner diameter of 18.8 cm, and a height of 40 cm is made of polyether ether ketone material as a sensing carrier, and the surface thereof is treated by plasma-enhanced chemical vapor deposition to form a diamond-like coating; S2: a ring-shaped elastic support belt and a laser-cut titanium alloy sawtooth ring are provided at the bottom of the sensing carrier, the sawtooth ring has a tooth depth of 15 mm±0.2 mm, a tooth inclination angle of 45°±1°, and a tooth tip curvature radius R=0.1 mm, and a fast-release lacing system made of aramid fiber bundle material with a breaking strength exceeding 3.5 kN is assembled at the top of the sensing carrier, and the fast-release lacing system is rigidly connected with the sensing carrier; S3: a micro-sensor array composed of a plurality of acoustic sensors and a plurality of temperature sensors is precisely arranged on the sensing carrier after surface treatment by a photolithography process, and is arranged according to layer positions of 0~10 cm, 10~30 cm, and 30~40 cm, and the interval between adjacent two sensors in the layer position of 0~10 cm is 4.7 cm, the interval between adjacent two sensors in the layer position of 10~30 cm is 3.1 cm, and the interval between adjacent two sensors in the layer position of 30~40 cm is 9.4 cm; S4: the surface of each acoustic sensor and each temperature sensor is subjected to silicon nitride encapsulation treatment by plasma-enhanced chemical vapor deposition technology to form a silicon nitride envelope patch; S5: a microcontroller and a micro-SD card are fixed on an acrylic partition plate, and are placed in an IP67 protection box on the ground; S6: the microcontroller is electrically connected with the micro-SD card, the plurality of acoustic sensors, and the plurality of temperature sensors respectively, and all analog signal paths use double-layer twisted shielding cables, and digital signals are transmitted after photoelectric isolation.

[0016] A method for measuring the depth of a bumblebee nest using a measuring device prepared by the method as described above, comprising the following steps: (1) selecting a preselected point according to the distribution of ground bumblebee nest holes, using a closed-loop control hydraulic servo geological drilling machine to vertically press into the preselected point at a constant rate of ≤5 cm / min, and monitoring the pressure and displacement curves in real time, and automatically reducing the penetration rate when the pressure increases by ≥5 kN / s; (2) when the titanium alloy sawtooth ring contacts the frozen soil layer, the spatial posture of the titanium alloy sawtooth ring is dynamically corrected by the ring-shaped elastic support belt embedded with a micro-strain gauge above, to ensure that the axis angle of the sensing carrier is <0.5°; (3) connecting the acoustic channel: connecting the output ends of the plurality of acoustic sensors with the 24-bit Σ-Δ analog-to-digital converter in the microcontroller; (4) Connect temperature channel: connect several temperature sensors with their digital interfaces to the 24-bit sigma-delta analog-to-digital converter in the microcontroller; (5) Start the microcontroller, which has a built-in analog-to-digital converter to convert the corresponding signals monitored by the acoustic sensor and temperature sensor into equivalent voltages, and enable the RTC module with a timing accuracy of ±2ppm to monitor the fluctuations of the acoustic wave and temperature signal over time; finally, all the collected raw signals are stored in real time on the Micro-SD card; (6) Use sound temperature data to generate a probability model to evaluate the depth of the nest: (1) When processing Micro-SD card data on a portable rugged computer, first process the acoustic signal and temperature signal respectively: use a 50kHz sampling rate for the acoustic signal and implement an anti-aliasing filter, and at the same time, apply a sinc filter to the temperature signal, finally output an effective value of 1Hz; (2) After completing the signal processing, execute the subsequent fusion algorithm: based on the layout parameters of the non-uniform array, use the generalized cross-correlation algorithm to calculate the depth of the sound source, with a spatial resolution of ±5mm; and combined with the real-time acquired temperature gradient data, construct a frozen soil temperature gradient model; correct the drift of sound velocity caused by temperature change; (3) Generate a probability distribution graph of the depth of the nest through maximum likelihood estimation, and then output the positioning result, which needs to meet the requirement of uncertainty <1cm under 95% confidence interval.

[0017] Compared with the prior art, the present application has the following advantages: 1. In the present application, a miniature sensor array composed of several acoustic sensors and several temperature sensors is provided, which can detect using sound and temperature signals, causing less physical damage to the frozen soil layer, and to the greatest extent protecting the fragile highland permafrost structure, surface vegetation and the nest itself, avoiding irreversible damage and interference to the underground living environment of the bee colony caused by traditional excavation methods, and meeting the core needs of highland ecological environment protection.

[0018] 2. In the present application, acoustic sensors and temperature sensors are laid out according to different horizons and different intervals, and by analyzing the vertical gradient change characteristics of the soil temperature under the position of the nest activity sound source, the vertical depth range of the nest can be more accurately evaluated. This dual signal fusion method effectively utilizes the inherent correlation between the depth of the nest and the local microenvironment, has higher target directivity and depth measurement reliability than single signal detection or blind excavation, and can overcome the interference caused by the heterogeneity of frozen soil.

[0019] 3、The application synchronously collects the acoustic physical field characteristics (including reflection / scattering characteristics of actively emitted sound waves, environmental sound signals) and temperature gradient distribution information of the target point underground soil through integrated sensors, and through fusion processing and intelligent analysis of the collected composite signals, the actual depth of the bumblebee nest built underground and other information can be accurately and efficiently determined without damage.

[0020] 4、The bumblebee nest depth data obtained by the application is a direct indicator of the adaptability of the bee colony to the permafrost environment. By long-term and large-scale monitoring of the bumblebee nest depth distribution and its changes, the influence of Qinghai-Tibet Plateau permafrost degradation on the survival environment of key pollinators, i.e., plateau bumblebees, can be clearly reflected, which provides a non-invasive and effective monitoring method for evaluating the changes of permafrost ecosystems and their ecological effects under climate change, and has important scientific research value. BRIEF DESCRIPTION OF DRAWINGS

[0021] The specific embodiments of the application will be further described in detail below with reference to the accompanying drawings.

[0022] Figure 1 The figure is a structural schematic diagram of the application.

[0023] Figure 2 The figure is the layout array of the acoustic and temperature sensors attached to the surface of the cylinder wall and the envelope in the application.

[0024] In the figure: 1-fast release lanyard system; 2-sensor carrier; 3-silicon nitride envelope patch; 4-annular elastic support belt; 5-titanium alloy sawtooth ring; 6-acoustic sensor; 7-temperature sensor. DETAILED DESCRIPTION

[0025] As shown in Figures 1-2 A measuring device for the depth of bumblebee nests in the permafrost region of the Qinghai-Tibet Plateau, the device includes a hollow cylindrical sensor carrier 2, a micro-sensor array, and a microcontroller and micro-SD card placed in an IP67 protective box on the ground surface. The microcontroller (Arduino Uno, Ivrea, Italy) and micro-SD card are signal receiving and storage devices.

[0026] The surface of the sensing carrier 2 is provided with a diamond-like carbon (DLC) coating, the bottom is provided with an annular elastic support belt 4, and the top is provided with a quick-release lacing system 1 in the circumferential direction; the annular elastic support belt 4 is installed with a titanium alloy serrated ring 5; the surface of the diamond-like carbon (DLC) coating is provided with the micro sensor array composed of a plurality of acoustic sensors 6 and a plurality of temperature sensors 7; the surface of each acoustic sensor 6 and each temperature sensor 7 is provided with a silicon nitride envelope sticker 3; a microcontroller is electrically connected with a micro-SD card, a plurality of acoustic sensors 6 and a plurality of temperature sensors 7 respectively. The acoustic sensors 6 and the temperature sensors 7 are connected to the ATmega328P microcontroller by wires and store the collected signals on the Micro-SD card.

[0027] The outer diameter of the sensing carrier 2 is 20 cm, the inner diameter is 18.8 cm, and the height is 40 cm.

[0028] The quick-release lacing system 1 is made of aramid fiber bundles, and its breaking strength exceeds 3.5 kN.

[0029] The inner wall of the annular elastic support belt 4 is embedded with a micro strain gauge made of metal foil or semiconductor material.

[0030] The serrated ring 5 of the titanium alloy has a tooth depth of 15 mm ± 0.2 mm, a tooth inclination angle of 45° ± 1°, and a tooth tip curvature radius R = 0.1 mm.

[0031] The plurality of acoustic sensors 6 and the plurality of temperature sensors 7 are unevenly arranged according to different layer positions and different spacings, and each layer position is provided with an acoustic sensor 6 and a temperature sensor 7.

[0032] The plurality of acoustic sensors 6 and the plurality of temperature sensors 7 are arranged according to layer positions of 0~10 cm, 10~30 cm and 30~40 cm, and the spacing between adjacent two sensors in the layer position of 0~10 cm is 4.7 cm, the spacing between adjacent two sensors in the layer position of 10~30 cm is 3.1 cm, and the spacing between adjacent two sensors in the layer position of 30~40 cm is 9.4 cm.

[0033] The frequency range of the acoustic sensor 6 (MAX9814, San Jose, California) is 0.022~22 kHz, and the gain is set to 40 dB. MAX9814 is a high-performance MEMS capacitive microphone preamplifier chip launched by Maxim Integrated (now Analog Devices).

[0034] The temperature resolution of the temperature sensor 7 (MLX90614, Ieper, Belgium) is 0.02℃.

[0035] The preparation method of the measuring device comprises the following steps: S1, a hollow cylinder with an outer diameter of 20 cm, an inner diameter of 18.8 cm, and a height of 40 cm is made of polyether ether ketone (PEEK) material as a sensing carrier 2. The sensing carrier 2 has excellent mechanical properties, and the tensile strength is not less than 100 MPa, and the impact toughness at -60°C is more than 30 kJ / m². The surface of the sensing carrier 2 is treated by plasma enhanced chemical vapor deposition (PECVD) to form a diamond-like carbon (DLC) coating, so that the hardness HV is not less than 800, and the frost abrasion can be effectively resisted.

[0036] S2, a ring-shaped elastic support belt 4 is arranged at the bottom of the sensing carrier 2, and a laser-cut titanium alloy (Ti-6Al-4V) serrated ring 5 is integrated, the tooth depth is 15 mm±0.2 mm, the tooth inclination angle is 45°±1°, and the tooth tip curvature radius R=0.1 mm; the top is equipped with a fast-release lacing system 1 made of aramid fiber bundle material with a breaking strength of more than 3.5 kN, and the fast-release lacing system 1 is rigidly connected with the sensing carrier 2. The fast-release lacing system 1 supports micro-damage disassembly and assembly cycle operation.

[0037] S3, on the sensing carrier 2 after surface treatment, a micro sensor array composed of a plurality of acoustic sensors 6 and a plurality of temperature sensors 7 is precisely arranged by a photoetching process, and is arranged according to the layer position of 0~10 cm, 10~30 cm, and 30~40 cm, and the interval between the adjacent two sensors in the layer position of 0~10 cm is 4.7 cm, the interval between the adjacent two sensors in the layer position of 10~30 cm is 3.1 cm, and the interval between the adjacent two sensors in the layer position of 30~40 cm is 9.4 cm.

[0038] As shown in Figure 2 , the micro sensor array is 36 micro sensors (24 acoustic sensors 6 and 12 temperature sensors 7), which are arranged in a non-uniform topology in the vertical direction. Nine acoustic sensors 6 and three temperature sensors 7 are arranged in the layer position of 0~10 cm below the ground surface, with an interval of 4.7 cm; twelve acoustic sensors 6 and six temperature sensors 7 are arranged in the layer position of 10~30 cm, with an interval of 3.1 cm; three acoustic sensors 6 and three temperature sensors 7 are arranged in the layer position of 30~40 cm, with an interval of 9.4 cm.

[0039] S4, the surface of each acoustic sensor 6 and each temperature sensor 7 is treated by plasma enhanced chemical vapor deposition (PECVD) technology for silicon nitride packaging, to form a silicon nitride envelope sticker 3. The thickness of the silicon nitride envelope sticker 3 is 3 μm, and the dielectric strength is more than 10 MV / m, which can realize signal fidelity and soil electrolyte isolation.

[0040] S5 Fix microcontroller and micro-SD card on the acrylic partition (40cm x 20cm) and put them into the IP67 protection box (size 30 x 20 x 15cm) on the ground.

[0041] S6 Electrically connect microcontroller with micro-SD card, several acoustic sensors 6 and several temperature sensors 7 respectively, ensure that all analog signal paths use double-layer twisted shielded cable (EMI shielding, transfer impedance <20 mΩ / m), and that digital signals are transmitted after photoelectric isolation.

[0042] A method for measuring the depth of a bumblebee nest using the measuring device, comprising the following steps: (1) Select pre-selected points according to the distribution of ground bumblebee nest holes, and use a closed-loop control hydraulic servo geological drilling machine (axial positioning accuracy ±2mm, inclination error ≤0.1°) to vertically press at a constant rate ≤5cm / min at the pre-selected points, and monitor the pressure (range 0-50kN, resolution ±0.1kN) and displacement curve in real time, and automatically slow down when the pressure increases by ≥5kN / s; (2) When the titanium alloy sawtooth ring 5 contacts the frozen soil layer, the spatial posture of the titanium alloy sawtooth ring 5 is dynamically corrected by the ring-shaped elastic support belt 4 embedded with micro strain gauges above, to ensure that the axis angle of the sensing carrier 2 is <0.5°; (3) Connect the acoustic channel: connect the output (analog voltage signal) of the several acoustic sensors 6 to the 24-bit Σ-Δ analog-to-digital converter in the microcontroller; (4) Connect the temperature channel: connect the several temperature sensors 7 through their digital interfaces (such as I 2 C) to the 24-bit Σ-Δ analog-to-digital converter in the microcontroller; (5) Start the microcontroller, its built-in analog-to-digital converter converts the corresponding signals monitored by the acoustic sensors 6 and temperature sensors 7 into equivalent voltages, and enables the RTC module with a timing accuracy of ±2ppm to monitor the fluctuations of sound waves and temperature signals over time; finally, all collected raw signals are stored in real time on the Micro-SD card; (6) Use sound temperature data to generate a probability model to evaluate the depth of the nest: ① When processing Micro-SD card data on a portable rugged computer (such as a ThinkPad X-240 equipped with a 2.4GHz i5 processor and 8GB RAM), first process the acoustic signals and temperature signals separately: use a 50kHz sampling rate for acoustic signals and implement anti-aliasing filtering, and use a sinc filter for temperature signals (including ambient temperature and circuit board temperature), and finally output 1Hz effective value (based on 10 samples per second per channel after sinc filtering); ②After signal processing, the subsequent fusion algorithm is executed: based on the layout parameters of the non-uniform array, the generalized cross-correlation algorithm (GCC-PHAT algorithm) is used to calculate the depth of the sound source, and the spatial resolution reaches ±5 mm; combined with the real-time acquired temperature gradient data, a frozen soil temperature gradient model (accuracy 0.01℃) is constructed; the drift of sound velocity caused by temperature change is corrected (frozen soil sound velocity temperature coefficient is about-0.3m / s / ℃); ③The probability distribution map of the honeycomb depth is generated through the maximum likelihood estimation (MLE), and then the positioning result is output, and the result needs to meet the requirement that the uncertainty is less than 1cm under the 95% confidence interval.

Claims

1. A measuring device for measuring the depth of a bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau, characterized in that: The device comprises a hollow cylindrical sensing carrier (2), a micro-sensor array, and a microcontroller and a micro-SD card placed in an IP67 protection box on the ground surface; the surface of the sensing carrier (2) is provided with a diamond-like coating, the bottom is provided with a ring-shaped elastic support belt (4), and the top is provided with a quick-release lacing system (1) in the circumferential direction; the ring-shaped elastic support belt (4) is installed with a titanium alloy serrated ring (5); the surface of the diamond-like coating is provided with the micro-sensor array composed of a plurality of acoustic sensors (6) and a plurality of temperature sensors (7); the surface of each acoustic sensor (6) and each temperature sensor (7) is provided with a silicon nitride envelope patch (3); the microcontroller is electrically connected with the micro-SD card, the plurality of acoustic sensors (6) and the plurality of temperature sensors (7) respectively.

2. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The outer diameter of the sensing carrier (2) is 20 cm, the inner diameter is 18.8 cm, and the height is 40 cm.

3. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The quick-release lacing system (1) is made of aramid fiber bundle, and the breaking strength is more than 3.5 kN.

4. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The inner wall of the ring-shaped elastic support belt (4) is embedded with a micro strain gauge made of metal foil or semiconductor material.

5. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The serrated ring (5) has a tooth depth of 15 mm±0.2 mm, a tooth inclination angle of 45°±1°, and a tooth tip curvature radius R=0.1 mm.

6. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The plurality of acoustic sensors (6) and the plurality of temperature sensors (7) are unevenly arranged according to different layers and different intervals, and each layer is provided with the acoustic sensor (6) and the temperature sensor (7).

7. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The plurality of acoustic sensors (6) and the plurality of temperature sensors (7) are arranged according to the layers of 0~10 cm, 10~30 cm and 30~40 cm, and the interval between the adjacent two sensors in the layer of 0~10 cm is 4.7 cm, the interval between the adjacent two sensors in the layer of 10~30 cm is 3.1 cm, and the interval between the adjacent two sensors in the layer of 30~40 cm is 9.4 cm.

8. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The frequency range of the acoustic sensor (6) is 0.022~22 kHz, and the gain is set to 40 dB.

9. The device for measuring the depth of the bumblebee nest in the permafrost region of the Qinghai-Tibet Plateau according to claim 1, characterized in that: The temperature resolution of the temperature sensor (7) is 0.02℃.

10. A preparation method of the measuring device according to any one of claims 1~9, comprising the following steps: S1: a hollow cylindrical sensing carrier (2) with an outer diameter of 20 cm, an inner diameter of 18.8 cm, and a height of 40 cm is made of polyether ether ketone material, and the surface thereof is treated by plasma enhanced chemical vapor deposition to form a diamond-like coating; S2: a ring-shaped elastic support belt (4) is arranged at the bottom of the sensing carrier (2) and integrated with a laser-cut titanium alloy serrated ring (5) with a tooth depth of 15 mm±0.2 mm, a tooth inclination angle of 45°±1°, and a tooth tip curvature radius R=0.1 mm; a quick-release lacing system (1) made of aramid fiber bundle with a breaking strength of more than 3.5 kN is assembled at the top and rigidly connected with the sensing carrier (2). S3 precisely arranging a micro-sensor array composed of a plurality of acoustic sensors (6) and a plurality of temperature sensors (7) on the surface-treated sensing carrier (2) by a photolithography process, and arranging according to the layer position of 0-10 cm, 10-30 cm, 30-40 cm, and the interval between the adjacent two sensors in the layer position of 0-10 cm is 4.7 cm, the interval between the adjacent two sensors in the layer position of 10-30 cm is 3.1 cm, and the interval between the adjacent two sensors in the layer position of 30-40 cm is 9.4 cm; S4 the surface of each acoustic sensor (6) and each temperature sensor (7) is subjected to silicon nitride packaging treatment by plasma-enhanced chemical vapor deposition technology to form a silicon nitride envelope sticker (3); S5 fixing the microcontroller and micro-SD card on the acrylic partition and placing them in the IP67 protection box placed on the ground; S6 electrically connecting the microcontroller with the micro-SD card, a plurality of acoustic sensors (6) and a plurality of temperature sensors (7), respectively, and ensuring that all analog signal paths use double-stranded twisted shielded cables, and digital signals are transmitted after photoelectric isolation.

11. A method for measuring the depth of a bumblebee nest using a measuring device prepared by the method of claim 10, comprising the following steps: (1) selecting a preselected point according to the distribution of ground bumblebee nest holes, using a closed-loop control hydraulic servo geological drilling machine to vertically press at a constant rate of ≤5 cm / min at the preselected point, and monitoring the pressure and displacement curve in real time, and automatically reducing the penetration rate when the pressure increases by ≥5 kN / s; (2) when the titanium alloy sawtooth ring (5) contacts the frozen soil layer, the spatial posture of the titanium alloy sawtooth ring (5) is dynamically corrected by the ring-shaped elastic support belt (4) embedded with a micro-strain gauge above, to ensure that the axis angle of the sensing carrier (2) is <0.5°; (3) connecting the acoustic channel: connecting the output end of a plurality of acoustic sensors (6) with a 24-bit Σ-Δ analog-to-digital converter in the microcontroller; (4) connecting the temperature channel: connecting a plurality of temperature sensors (7) through their digital interfaces with a 24-bit Σ-Δ analog-to-digital converter in the microcontroller; (5) starting the microcontroller, the built-in analog-to-digital converter converts the corresponding signals monitored by the acoustic sensor (6) and the temperature sensor (7) into equivalent voltages, and the RTC module with a timing accuracy of ±2ppm is enabled to monitor the fluctuations of the acoustic and temperature signals over time; finally, all collected raw signals are stored in real time on the Micro-SD card; (6) generating a probability model using the acoustic and temperature data to evaluate the depth of the nest: ① when processing the Micro-SD card data on a portable rugged computer, the acoustic signal and the temperature signal are processed respectively: the acoustic signal is sampled at a rate of 50 kHz and anti-aliasing filtering is performed, and the temperature signal is subjected to a sinc filter, and finally an effective value of 1 Hz is output. ②After the signal processing, the subsequent fusion algorithm is executed: based on the layout parameters of the non-uniform array, the generalized cross-correlation algorithm is used to calculate the depth of the sound source, and the spatial resolution reaches ±5 mm; combined with the real-time acquired temperature gradient data, a frozen soil temperature gradient model is constructed; the drift of sound velocity caused by temperature change is corrected; ③The probability distribution map of the honeycomb depth is generated through maximum likelihood estimation, and then the positioning result is output, and the result needs to meet the requirement that the uncertainty is less than 1 cm under 95% confidence interval.

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