Device for improving farmland soil of coastal mud flat reclamation areas by combining short-term rapid drainage desalination with long-term control accumulation of salt, and drainage method thereof

Abstract

The invention provides a double-layer composite underground drainage device for improving farmland soil of coastal mud flat reclamation areas by combining short-term rapid drainage desalination with long-term control accumulation of salt. The device comprises a short-term shallow straw gap underground drainage system salt leaching channel, a stream collecting and fixing water absorption subdrain and an open drain on the coastal mud flat saline-alkali soils, wherein the salt leaching channel is positioned above the stream collecting and fixing water absorption subdrain and is arranged with the stream collecting and fixing water absorption subdrain in parallel; the open drain is arranged at the water outlet end of the subdrain and the salt leaching channel; the water head difference is formed between the open drain and the coastal mud flat ground surface. The drainage method method comprises the steps of leaching the salt in the coastal mud flat soil by using the percolation generated by irrigation or rainfall, enabling the salt to enter into the shallow straw underground drainage system salt leaching channel and the stream collecting and fixing water absorption subdrain along the stream, discharging the salt in the soil along the water, and leading to the open drain. After the underground drainage system salt leaching channel formed by shallow straw gaps is deformed caused by pressure, the channel can still keep excellent drainage and salt elimination performance, so that the technical problems that the plastic corrugated subdrain is easy to deform and not suitable for shallow burying after being subjected with burying and operation agricultural implements dynamic load pressure can be solved.

Description

technical field [0001] The invention relates to a double-layer combined underground drainage device and a drainage method for improving farmland soil in coastal tidal flat reclamation areas by combining short-term rapid drainage desalination and long-term control of salt return. Background technique [0002] my country's coastline is long and the proportion of plain coast is large, while the coastal soil contains more saline-alkali components, and its poor physical and chemical properties cause the growth of most plants to be inhibited to varying degrees, or even unable to survive. Efficient and reasonable improvement and utilization of a large area of ​​coastal coastal saline-alkali soil can alleviate the contradictions between the dwindling cultivated land, the shortage of fresh water resources and the increasing population. [0003] So far, there are basically two ways to control and utilize saline soil in my country: one is non-biotechnological measures including tillage...

AI Technical Summary

Problems solved by technology

[0005] In saline-alkali land, the method of setting fixed water collection concealed pipes underground is usually used to achieve salt drainage. The material of the concealed pipes is usually plastic corrugated pipes, but the plastic corrugated concealed pipes are volatile after being subjected to the dynamic load pressure of buried soil and operating agricultural machinery, and are not suitable for shallow burial. Most of the previous methods are to lay a large number of shallow and dense open ditches in the field to accelerate soil desalination. This method wastes a lot of land, is easy to silt shallow, requires a large amount of engineering, high investment, and poor effect

Images