Gas sampling device applicable to soil at different depths in perennially frozen soil zone

Abstract

The invention discloses a soil gas sampling device suitable for different depths in permafrost regions. Its structural feature is that the hollow gas collection cavity is a double-layer cylindrical cylinder, and the inner and outer walls of the cylinder are evenly opened with ventilation holes. The bottom of the cylinder and the The top is sealed; the semi-permeable membrane is located in the middle of the double-layer cylindrical cylinder, and the hollow gas collection cavity is closely connected with the suction pipe. Valve connection; the left and right ends of the four-way valve are respectively connected to an air bag, and the remaining port of the four-way valve is connected to the straight-through valve. The port of the straight-through valve is provided with a silicone plug, and the syringe is inserted into the silicone plug. The device is easy to install, has low manufacturing cost and reasonable design, and can be widely used in the collection and monitoring research of greenhouse gas emissions from farmland, garbage landfills, grasslands and frozen soil regions.

Description

technical field [0001] The invention relates to an auxiliary equipment for soil environment research and monitoring, in particular to a soil gas sampling device suitable for cold regions, especially permafrost regions. Background technique [0002] In recent years, carbon-containing greenhouse gases (CO 2 、CH 4 ) emissions have become a hot spot in international carbon cycle research. For cold regions, especially permafrost regions, global warming and changes in the freeze-thaw pattern will lead to fundamental changes in the carbon emission process of the soil, releasing a large amount of CO into the atmosphere. 2 and CH 4 Such as greenhouse gases, enhance the trend of climate warming, and form a positive feedback effect on climate change. Therefore, during the freeze-thaw process of soil in permafrost regions, accurate collection of soil gas samples is a prerequisite for studying the impact and mechanism of global warming and freeze-thaw pattern changes on soil carbon e...

AI Technical Summary

Problems solved by technology

During the excavation of the soil profile, the soil is strongly disturbed; and when the gas collection pipe is inserted horizontally into the soil, the micropores on the collection pipe are easily blocked

Furthermore, when the soil water level is high or the soil moisture infiltrates, it is easy to accumulate water in the collection pipe, making it difficult to collect soil gas.

Therefore, the device is used for the collection of soil gas. It is troublesome to install and arrange, and it disturbs the soil greatly, which leads to the distortion of the gas sample collection results. Moreover, due to the influence of the groundwater level and the infiltration of soil moisture, water is easy to accumulate in the collection pipe, making it difficult to collect. to soil gas

Therefore, this device is more suitable for unsaturated sandy soil areas, so it is difficult for this device to collect soil gas samples in cold regions

[0006] For another example, the invention patent with the application number 201110159118.5 discloses "a buffer soil gas sampling device", which is essentially used to measure CO 2 、CH 4 and N 2 The static box of greenhouse gas flux such as O is improved after adding an air bag. Although this device better solves the problem that the existing soil gas sampling device is easy to cause forward or reverse air leakage and soil gas leakage due to the lack of buffer pressure structure. Release defects that are easily suppressed by the internal air pressure of the box, but this device can only be used to measure the total emission flux of soil gas on the surface, and cannot collect soil gas at different levels inside the soil

Therefore, for the collection and analysis of soil gas at different depths in cold regions, the device cannot meet the requirements

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