Research On The Influence Factors Of The Transfer Of Water And Salt Of The Low Plain In Western Jilin Province

The western Jilin porvence is one of the most salinization area in china. Because of the excess utilization and affection of nature condition, the salinization of soil accelerate these years, which represent as the expands of square and aggravation of salinization extent. The prevention and improvement of solization is the center of this problem. In order to solve this problem we need to comprehend the transfer of water and salt and the influence factors. It is one of the basic theory to solve the salinization and groundwater pollution.The salinization in western Jilin province has certain space-time characteristic. According to the space-time characteristic, the servere salinization area is mainly around the low lake marsh. The moderate salinization area is mainly in the transition area between oblique plain and low lake marsh of high plain. the light salinization area is mainly in the east and west of the low plain and the valley of high plain. the studying area is in the semiarid zone of our country. The salinization characteristic is obviously rhythmicity. In winter the salt in the soil is the lowest, and the movement of water and salt is slow, variation of salinity is small. In spring and autumn the salt in the soil is very high. So it is the period of uprise of salt, especially in spring. Summer (rainy period) is the desalt period.according to analyse of lots of data,the main influencing factors on shaping of salinization of soil in the western Jilin province are following:(1) meteorologic factors: It is wet, warm and rainy in summer and autumn in the research area. It is mainly of leaching process, and the concerntration of salt decreases. In dry season, with the icrease of envaporation, a large amount of salt is enriched in soil. Soil salinization is accelerated by frequent alternant desalination and enrichment of salt.(2) geologic factors: The research area is the an area with high enrichment of salt transfer, and it is propitious to the enrichment of salt. The properties of soil directly influence the movement of water and salt in soil.(3) The influence on soil salinization by hydrogeochemical environment: Whether caplillary water of soil reaches surface, the enrichment of salt occurs or not and how much salt can be enriched in soil depends on the depth to phreatic water table. When runoff is weak, the movment of groundwater is mainly of vertical direction, in favor of the enrichment of salt. The types of salinization are influenced by hydrochemical types. When the depth to phreatic water is lower than critical depth of uprise of salt, the higher content of TDS is, the more severe level of soil salinization will be, and less severe under the opposite condition. The content of salt in soil regulates with dissolved ions. When it is much high, plants can not survive, and salinization will be caused.(4) Surface water factors: The surface water system is not well developed in the research area. The groundwater runoff is weak, and is maily of vertical movement. The salt in water accumulates, causing soil salinization. The surface water indirectly influences soil salinization. Analyzes based on water quality and soil data in many years,from the character of soil's water and salt space-time,the connection between soil's water and salt and the character of groundwater,As a specific soli under certain condition, the mechanic of water-salt movement in salinized soil is a process of water and salt moving upward and accumulation of salt. Generally, salt ions in soil move with soil moisture, and change with variation of meteorologic and groundwater dynamic condition. When water and soil move upward and evaporate, salt is highly accumulated and uprised. When water and soil move downward, salt desalination occurs as a result of leaching process.Analyzes the cause of salinization in western Jilin province from the point of ecological and geological environment. The author thinks the formation process of salinazation in western Jilin province is the combination of the fragile ecological and geological environment and human's irrational activities. the fragile ecological offer impersonality basic for the happen of salinization;in somany factors of ecological and geological environment,the most important are climate,geology,hydrologic geology and human's activities. geological environment offer matter source for salinization and lick into shape developed space;climatic conditions decide inevitability for the happen of salinization, especially freeze-thaw action can't be ignored; hydrology and hydrogeologic condition bring direct influence; human's irrational economic activities spring and prick up the happen of soil salinization.The research indicates that the problem of salinization was more and more serious and complex influencing factor in research region. improved radically for the problem of salinization,we must discussed the mechanism of salinization,the character of soil's water and salt space-time,the influencing factor and the process of water and salt moved,adjust measures to local conditions,fathered radically the problem of salinization,protected entironment。...