The Research On Sea Water Invasion And Soil Salinization

The sea water invasion is the phenomenon that in coastal area excessively mining ground water causes the subsoil water level drop on the large scale. Hydrodynamic force balance between the sea water and the fresh water is destroyed, leading to the salty-freshwater contacting surface motion to the landward side ". Its primary factor is the artificially and excessively mining ground water and creates destruction of hydrodynamic force balance . In domestic, Dalian was discoveried first sea water invasion in 1964. Sea water invasion geology disaster is very universal ,especially in Huang sea and Bo Sea's coastal area. Along the sea coast from north to south, the Laizhou bay area in Shandong Peninsula, Dalian and so on was discovered sea water invasion. The text elaborates the sea water invasion's influence factor , origin analysis, the invasion way and the harm. Taking the Muchengyi area in Dalian as example, uses the experimental sampling and physics and chemistry analysis method to analyze chloride ion and other chemical compositions in ground water .As chloride ion density 250mg/l is standard, showing the sea water invasion degree and its influence, determining this area in the sea water invasion influence obviously.Under the research of sea water invasion geology disaster background, the text studies the sea water invasion geology disaster for the first time to the farmland soil influence. On the sea water invasion influence, after ground water irrigate the farmland and massive soil moisture evaporate or discharge, the salinity stores on the soil surface or in the soil, causing the soil salinization. Selecting representative's farmland soil as sampling to mainly analyze its physical property to appraise whether the soil has salinization and its degree. The salinization's essence is the process that the salinity stores in the soil .Improper irrigation method or bad irrigation water quality can cause the soil salinization. Muchengyi area in Dalian induces the soil salinization the factor as follows : Irrigation water has high salinity content , high hardness index ; The non-periodical water-using, frequently irrigating, excessive water volume, thus intensified the sea water invasion influence, the further pollution ground water, indirectly caused the fresh water resources on short. The soil salinization causes the ecological environment worsen, and harm agricultural production and so on.To the prevent the local soil salinization and restore farmland soil ecology function, needing to regulate the ground water and reduce harm of the sea water invasion . The seawater invasion preventing and controlling measure includes: controlling and adjusting ground water mining, increasing ground water supplies, reducing water used, divide the water supply, taking non-local water and desalinating sea water and so on.