Observation device for farmland soil solute transport

Abstract

The invention discloses an observation device for farmland soil solute transport, which comprises an observation pipe which is perpendicular to the ground, the upper part of the observation pipe is higher than the ground, the lower part of the observation pipe is buried in soil, the upper port of the observation pipe is provided with a single-hole cover or cap, and the upper pipe wall of the observation pipe is provided with a breather pipe; the water collecting bottle is positioned at the bottom end of the observation pipe and is communicated with the observation pipe; the water suction pipe is buried in a soil layer with a specific depth, one end of the water suction pipe is horizontally connected to the side wall of the lower part of the observation pipe, the other end of the water suction pipe is plugged by a solid rubber plug, and water-permeable holes are formed in the water-permeable pipe; the sampling device consists of an air extractor, an air suction pipe, a water guide pipe, a double-hole cover and a sampling bottle, the air suction pipe and the water guide pipe are fixed on the bottle plug and extend out of the lower surface of the bottle plug, the other end of the air suction pipe is connected with air extractor, and the water guide pipe extends into the water collection bottle through the observation pipe. The horizontal permeable water absorption pipe can increase the infiltration contact area of a research target soil layer, the sampling range is expanded, and the representativeness of a sample is improved.

Description

technical field [0001] The invention belongs to a device in the technical field of soil environment monitoring, and is specifically mainly applied to dynamic monitoring of solute transport in farmland soil and related experimental research in the fields of agriculture, water conservancy and ecological environment. Background technique [0002] The movement of soil water is not only an important link in the hydrological "four-water transformation", but also an important carrier and driving force for soil solute transport. With the effects of rainfall and irrigation infiltration, crop absorption, surface evaporation, soil capillary and pore adsorption, and groundwater recharge, the water and salt in soil layers at different depths change dynamically. Soils in nature are mostly staggered and complex layered structures, with great differences in physical and chemical properties between different depths, and their water infiltration capacity and solute transport characteristics a...

AI Technical Summary

Problems solved by technology

Traditional research methods mainly rely on farmland observation tubes for soil solute transport experiments. This research method has the following problems: If the flower tube (permeable hole) of the observation tube is long, the soil solution at different depths enters the tube and mixes, making it difficult to distinguish soil infiltration. The soil layer depth of liquid cannot achieve the purpose of stratified sampling; if the opening position of the observation tube flower tube (permeable hole) is only limited to the designed target test depth, although stratified sampling can be satisfied, the length of the permeable hole is short and effective The water absorption area is small, the sampling representativeness is poor, and the amount of water entering the tube is small, which cannot meet the requirements of test accuracy and sampling test

In order to solve this problem, a large number of researchers carried out simulation experiments based on indoor soil columns, test pits, and measuring cylinders, and set sampling pipes horizontally in the soil layer at a specific depth. Although the purpose of layered sampling can be achieved in this way, the indoor simulation experiments The environment is quite different from the actual farmland soil environment outdoors, and the conclusions obtained are difficult to reflect the migration law of water and salt solutes in farmland soil in the natural state

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