| In arid areas, the production and living space for residents are mainly concentrated in oases. Therefore, the oasis land resource has become the material foundation for the survival of the local people. However, in recent years, with the improvement of living standards, and the increase of production strength, the coupling relationship between man and nature is more and more inharmonious, which made the fragile ecological environment worsen. And frequent natural disasters, ecological degradation of the environment; especially the aggravation of soil salinization brings the serious influence to residents. Based on this, the article from the soil salt content and its influencing factors of space and time differentiation, taking Keriya oasis as the study area, using classical statistical analysis, geostatistical analysis and spatial analysis method to analyze the spot sampling data, instrument detection data, laboratory test data, social survey data and statistical data, and then looking for soil salinity and its affecting factors differentiation rule. At the same time, through the geographical weighted regression analysis and linear regression analysis methods study the natural environment and social cultural influence factors respectively, and calculate the contribution rate of each influence factor on the soil salt content. Finally, by using the coupling degree model, calculate the correlation degree among the soil salinity and its impact factors, to illustrate the credibility of factor selection. The main results are as follows:Ⅰ In the study of the space and time differentiation of deep soil,its change trend are evident. In time, the soil salinity of each layers fluctuation in the spring and summer is larger, in the autumn and winter is smaller, and it reaches a maximum of the year from April to June, from November to January the following year to achieve the minimum value of the year. The surface soil salt content changes with the seasons are most volatile. With the increase of soil depth, the salinity fluctuations with time trend become slower. In space, the content of soil salt overall distribution basically shows the trend of West is high and low in the East, the North is high and the South is low. From 0 ~ 20 cm, the salt in northwest is heavy and its distribution is complicated; the salt distribution in southeast is balance, and its value is bigger, variable rate is higher. In 20~40cm, west of salt distribution is not uniform, no regularity, while the East is more uniform, especially in the northeast part of the oasis area salt decreased gradually from north to south, and its value decreased rapidly from the surface. In 40 ~ 60 cm, the salt distribution is regular, and it is higher in the West than that in the East, the North is higher than the South, the salinity values from the upper layer to the layer variable rate decreases gradually. In 60-80 cm, salt transition from northwest to southeast, west of transition zone soil salinity distribution is relatively complex, and in the east of border salt distribution is balance. In 80 ~ 100 cm, the spatial distribution of soil salt from west to east and from north to south are decreasing gradually, more regularity; the value of the northwest is higher than the southeast.Ⅱ In nine of the natural environment factors influencing soil salt content in Keriya oasis, the groundwater depth in the West is higher than the East, the North is higher than the South, it is negatively correlated with the value of soil salinity, and its contribution to soil salinity is maximum. Secondly, the overall terrain shows that the South part is higher than the North, and the West is higher than the East, which is in contrast with the distribution trend of soil salinity. From east to west, the sampling points farther from the river, which is against with the soil salt distribution trend of decreasing from the west to the east, and the influence degree is high. The overall presentation of groundwater salinity is the South is higher than the North, the West is higher than the East, which is broadly consistent with the spatial distribution of soil salt content. Both showed a positive correlation, but its contribution to soil salinity is minimum. Spatial variation of soil water content on the whole present west is high and middle is low, its distribution is regular. It shows a positive correlation with salinity, but also has little influence on the salinity. Groundwater temperature decreases gradually from northwest to Southeast, its distribution is regular. Soil salt content and its distribution in space roughly the same, and its contribution is smaller to the soil salt.Ⅲ In ten of the social and humanistic factors affecting soil salt content in Kaerke, the distance between the sampling point and the village, and the distance between the sampling point and the main road, household per capita net income have large influence on the soil salinity. But crop yields, irrigation water and fertilizer usage force is small. In Yingbage, power consumption, distance between the sampling point and the village, and family average annual income have big contribution to the soil salt content. But the influence of the crop area, family population, and water consumption is small.Ⅳ Using the coupling model calculate the coupling degree of natural environmental factors and social humanities factors. The results show that in the natural factors, in addition to terrain factors, the coupling degree of the rest of the factor and the soil salt content was above 0.99, belongs to the polar coordinate coupling stage, and terrain belongs to low coordination separation stage. In the social factors of Kaerke, in addition to irrigation water consumption, the coupling in 0.79, is the high coordination running-in stage, its coupling with each factor all above 0.9, belong to the polar coordinate coupling phase. In Yingbage, in addition to the family per capita net income of the coupling is 0.49, belong to the coordination of antagonism stage, its coupling with each factor all above 0.8, belong to the polar coordinate coupling phase. |
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