Study On Soil Salinization Spatial Distribution And Its Influencing Factors In Wu Liang Suhai Basin

Hetao Irrigation District in Inner Mongolia is one of the most serious soil salinization area in our country. Due to the influence of natural conditions and human excessive use, soil salinization region expands year by year, and the trend of the development of the salinization degree is accelerated. Wu Liang Suhai valley is one part of the hetao irrigation district, also is one of the most serious regions of soil salinization. The ecological environment has noticeable salinization characteristics, namely, volatility, transitional and instability. So if you want to reasonably prevent and govern Wu Liang Suhai basin soil salinization, you must study soil salinity spatial distribution pattern and distribution rule of Wu Liang Suhai watershed.In this essay, the research is upon the detailed investigation of Wu Liang Suhai basin environment background. field sampling was taken in August 2012. Soil salt and pH were tested in the laboratory, and then the experimental results were analyzed. On the basis of soil salinity theory and study method, soil salinization contour map and pH contour map of wu Liang Suhai basin was drawed by using Surfer interpolation software. The results mainly reveal the spatial distribution pattern and vertical distribution structure of soil salinity in Wu Liang Suhai watershed. Finally on the basis of above research, citing the research achievements of predecessors, Qualitative analysis of the soil salinity formation reasons and its influencing factors was done. The aim is to provide a scientific basis for soil salinization prevention and governance.The main research conclusions are as follows:(1) Soil salinization degree in Wu Liang Suhai watershed contains five levels, including normal soils, mild salinization, moderate salinization, serious salinization, salinization respectively. There is more normal soil and slight saline soil in the whole basin. So there is few moderately saline soil and heavy saline soil. The study area has moderate alkaline soil, alkaline soil and strong alkaline soil, and mainly is alkaline soil in Wu Liang Suhai watershed.(2) The average soil salt content is different because of the different ways of land use. In this study the cultivated soil salinization has strong variability. The semi-fixed sand has medium variability. The consequences indicated that the two different land types affected by various factors have a great degree of variation.(3) In the alike land-use way, the significant difference among the soil salt content and pH in different layers is not obvious. Overall, the degree of salinity and pH decrease along with the deepening of the soil.(4) From the spatial scale, the soil salinization in Wu Liang Suhai basin is not particularly serious, and mainly has normal soil and slight saline soil. The salt content is much high in some area. The salinization is fearful in center district, and has a trend of gradual reduce from the center to all around. The soil alkalization is serious, mainly is alkaline soil. From the vertical distribution, along with the deepening of soil, soil total salt content and pH value has a decreasing trend, and the area in which the upper regions with high soil salinity has relatively high soil salinity and pH in the under.(5) The soil salinization in Wu Liang Suhai basin is closely related to climate, groundwater, soil texture and human activities. Weather determines the trend of the spatial pattern of soil salinity, and groundwater decides the definite distribution of salt. Usually soil texture and human activities first affect groundwater condition and then indirectly influence the spatial distribution of soil salinization.The study results of this paper chiefly has two worth, one is the broad theoretical significance; the second is providing theoretical basis for prevention and control of land salinization.