Ecological Characteristics Of Soil Water In Fencing Sandy Land

In arid environment condition, soil water is an very important environmental factor. Especially, soil water is a key factor that affects vegetable survival, growth and environmental upholding for vegetation in arid desert area. It directly affects restoration and rebuild of degradation ecosystem. Fencing sandy rearing forest and grass is one of important measure in restoration and rebuild of degradation ecosystem in current desert area.Based on field experiment and measure data, ecological characteristics of soil water in different fencing sandy land in arid desert area and vegetation restoration effect of soil water variation in fencing sandy land were analyzed. In representation of Artemisa arenaria DC population, observing and researching vegetable restoration effect of soil water variation in fencing sandy land. The results indicate as follow:(1)With the vegetation development constantly in fencing sandy land, soil water utilization of vegetation increased. It made soil water content and soil water storage reduced with the increase of fencing time in sandy land. In descending order, soil water content in different fencing sandy land is:mobile sandy land>fencing two years sandy land>fencing five years sandy land>natural restoration sandy land>natural+ artificial restoration sandy land>artificial restoration sandy land. The order of soil water storage in different types fencing sandy land is: mobile sandy land>fencing two years sandy land>fencing five years sandy land>natural restoration sandy land>natural+ artificial restoration sandy land>artificial restoration sandy land.(2)Soil water content remarkably varied and below 60cm soil layer decreased with the increase of fencing time, the soil water content decreased from 25.62~29.84 g.kg-1 to 18.02~22.82 g.kg-1 with the coefficients of variation ranging from 37.17% to 59.18% in 60cm~100cm soil layer, and the deep layer soil water has tendency to stabilize with the increase of fencing time.(3)In the same site condition, soil water of each layer with fencing five years sandy land was less than distinctly fencing two years sandy land. Especially in 60～80cm layer, soil water content is very distinct.In all fencing time, soil water of each layer with fencing five years sandy land was always lower than mobile sandy land.(4)In natural restoration, natural+ artificial restoration and artificial restoration three different restoration pattern, the soil water is different, natural restoration >natural+artificial restoration>artificial restoration.(5)Sandy land soil water content decreases with the increase of biomass, the more biomass of above-ground vegetation, the less soil water content. The soil water contents are distinct in different vegetation types. Thermopsis lanceolateR.Rr herb> Artemisia arenaria krasch half bush> Caragana korshinkiiKom bush.(6)Soil water content of Artemisa arenaria DC root system firstly increased then declined with the soil depth increased on different sand lands. The descend order is mobile sandy land>fencing sandy land>semi-fixed sandy land. The soil water content of mobile sandy land is 1.02%~5.93% from surface to deep layer, the soil water content below 30cm soil layer is higher remarkably the surface. The soil water content of semi-fixed sandy land is 0.65%~1.91% from surface to deep layer, the soil water content increased mildly with the soil depth increased. The soil water content of fencing sandy land is 0.74%~2.45%, amplitude and the soil water variation from surface to deep layer are moderate.(7)Total root biomass of Artemisa arenaria DC was changed in different sand land types. The root biomass order is mobile sands land(122.43g)>fencing sands land(106.35g)>semi-fixed sands land(90.15g).(8)In 0~40cm soil layer, in different type sandy land 75% roots biomass of Artemisa arenaria DC were existed. The proportion of taproot biomass of Artemisa arenaria DC in 0~20cm to total root biomass is the best, taproot biomass of mobile sandy land is maximum(80.56g,the percentage 65.80%); taproot biomass of fencing sands land is minimum(63.62g,the percentage 58.88%). But lateral roots biomass of fencing sand land is maximum(43.73g,the percentage 41.12%), lateral roots biomass of semi-fixed sandy land is minimum(23.26g,the percentage 29.10%),however, lateral roots biomass of mobile sandy land is 41.87g,the percentage lateral roots biomass of mobile sandy land to total root biomass is 34.20%, less fencing sandy land.(9)The correlation analysis shows that: soil water content, roots biomass of Artemisa arenaria DC and roots water become positive relativity in different types sandy land. The sandy land soil water content and roots biomass of Artemisa arenaria DC relativity order are mobile sandy land(0.990)>fencing sandy land(0.973)>semi-fixed sandy land(0.961); The sandy land soil water content and roots water of Artemisa arenaria DC relativity order are mobile sandy land(0.977)>fencing sandy land(0.938)>semi-fixed sandy land(0.929).