Study On Soil Moisture Factors And Storage Model Of Xunyang Dam In Southern

Qinling is our country north-south important geographical boundaries. It plays an important role in the maintenance of natural ecological system.Since the implementation of natural forest protection project in1988, the forest coverage is increasing in Qinling region, yet the forest soil pondage, thus improving the soil environment of Qinling. Based on this, the soil moisture research for soil moisture in qinling rational utilization and sustainable development has important significance.In this paper, Qinling mountains as the research object. Through literature collection, design of experiment and the field investigation and soil samples, with the aid of SPSS, GS+, SAS analysis softwares, the methods of mathematical statistics, the multiple regression analysis to deal with the sample data, analyzes the research in different land types of soil moisture, organic matter, bulk density and grain size of the soil physical and chemical properties. Discuss spatial distribution, influence factors, the main control factors of soil moisture.Soil water storage capacity prediction models are established.To provide theoretical and practical basis for the space of soil moisture in Qinling Mountains Xunyang dam area utilization.In this paper, the main contents and conclusions are as follows:(1) Under different land types,The soil organic matters are discriminately in sunny slope and shady slope. The variation range was between39.6g/kg and59.78g/kg. he average soil bulk density value of sunny slope and shady slope was no difference, and variation range was between1.14g/cm and1.32g/cm. The degree of variation of soil organic matters and bulk density is a weak or moderate in each type of land use. The soil is silt-based,and average content of coarse silt come to40.32%.The median size of soil particles change from11.75μm to11.75μm, and mean grain size is from16.26μn to181.31μm.(2) The average soil moisture was ranging from17.10%to21.87%in the studied area.Under different land types, the average soil moisture have the same changing in sunny slope and shady slope. But, the differentia between sunny and shady slope is different in the same land use type. Soil moisture of each layer are mostly medium variation degree in sunny slope, and hady slope is a weak variation. (3) Soil moisture content in the study area has no obvious effect in north-south direction. They are both ends slightly lower than middle, smooth transition characteristic.In west-east direction is also increased gradually first, and then decreased slowly in the trend line,present the inverted U shape.This is to say upper and bottom are lower than middle slope. The layers of soil moisture in the study area belongs to the strong or moderate spatial autocorrelation, and a weak spatial dependence in the entire section. Experiment of different soil moisture variation function model of the optimal choice is:0to10cm for the gaussian model,10-20cm and20to30cm for index model,0to30cm soil layer for the linear model. The section has a higher percentage of random variation, and a weak spatial correlation.(4) In the part of soil layers, the soil moisture and slop,organic matte soil have a significant correlation, soil bulk density and moisture is extremely significant correlation.And the particle size, slope direction and soil water has no relevance. Application of RDA comprehensive analysis on the influencing factors of soil moisture, found associated with soil moisture level of high and low sorting for slope, organic matter, silt, sand, clay, slope position, slope direction, soil bulk density, soil utilization types.Slope and organic matter are main controlling factors of soil moisture content in differentiation of the slope surface.(5) According to multiple regression analysis, the various types of land use of the optimal model are establishing. These models of soil water storage capacity are through the accuracy test, and the prediction accuracy of95.74%or more.so, they can better predict the area of soil water content.With the increase of depth, showed a trend of increase of the relative error, and the corresponding precision is reduced.