| Soil salinization is an important environmental problem which curbs the agricultural productivity and ecological environment in arid and semi-arid region, affects social prosperity and limits the economic development of northwest China. In the factors which influence the formation and development of soil salinization, surface evaporation, as a comprehensive climate index which impacts the distribution of soil salt, is the main method to analyze the influence of climate change on temporal distribution of soil salt.Through to the simulation of soil salt content and surface evaporation, analysis of basin spatial and temporal variation characteristics of soil salt and surface evaporation in manas river basin from 1990 to 1990. Analysis the correlation of both the change of climate change on soil salt basin, the influence of time and space distribution. This study used field sampling data and remote sensing image construction of manas river basin surface salt quantitative inversion formula, get the manas river basin from 1990 to 2015, the surface soil salt content distribution; Using SEBS model site and meteorological data from 1990 to 2015 in the study area is calculated surface evaporation quantity distribution, the inversion precision can satisfy the requirements of research; Through both within the basin and the different land use types on the correlation of change, analyze the effect of climate change on time and space distribution of soil salt. The main conclusions are as follows:(1)Soil salinization is mainly distributed in the central and northern region of Manas River. The salinization in the central part is in zonal distribution, and it’s mainly located in Kuitun, Manas, and some areas in No. 8 agriculture production division, like 141, 142 and 144 regiments. However, in the northern part, it mainly distributed around Manas River and stretches to Gurbantunggut Desert. There are two sharp declines in the total area of soil salinization. The first one is from 1995 to 2000, during which the area declined 17.42%. The changes are mainly in severe salinization areas. The second one is from 2010 to 2015. The changes are mainly in moderate salinization areas, and there is a decline in slight salinization areas.(2) The change of monthly total evaporation in Manas River is in the shape of inverted U. By comparing the mean of surface evaporation in different months, it can be concluded that the evaporation in April and June is greater than that in August and October. In temporal distribution, the surface evaporation in irrigation areas changes with the quantity that crops need. The greatest evaporation is in August, the mean of which is 25.12 mm. There is great change in evaporation in northern desert areas. From 1995 to 2015, the mean of evaporation increased by 3.3 mm, the growth of which is 1.5%.(3) From 1995 to 2005, surface evaporation bears the greatest significance with non-saline land’s turning into other types, in which non-saline land’s turning into severe salinization is the highest with the correlation reaching 0.67. There is a negative correlation between surface evaporation and severe salinization’s turning into other types, in which severe salinization’s turning into non-saline land has the highest correlation,-0.757. The evaporation capacity determines the rate of soil salt accumulation to some extent. The increase in evaporation bears a positive correlation with the deepening of soil salinization. Water supply in irrigation areas is relatively abundant. Evaporation and transpiration take away water from soil and plants. Soluble salt in water stays on the surface of soil, leading to the accumulation of salt on the surface. |
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