The Study Of Soil Moisture Bearing Capacity Of Stand On Slope Of West Of Shanxi Province

As the core of the ongoing "Mountain greening and water clearing" project on whole loess plateau, recovery and reconstruction of vegetation, its way of plantation, pattern, and consequent interest of ecology and economy to vegetation is largely depending on the water resources bearing capacity of the region. In this paper, we have used field experimental data, field surveyed data and in the lught of other research results of analysis behavior from rainwater to soil moisture in extent, directions and influential factors involved in this matter firstly. The author had also put forward the formation of soil moisture resources and its distribution patterns in the whole region. From the point of view in system ecology and quantity ecology, and the author also analyse the spatial characters of soil moisture quantity and the yearly changed volume of the loess plateau, and hence to analysis the suitable vegetation distribution arrangement, to calculate the net primary productivity of vegetation, to answer the bearing capacity of soil moisture resources etc. Therefore the vegetation recovery can be based on sound scientific basement. Through two years studying, the paper had made progress in many aspects.In the paper, we analysis the character of precipitation of experimental watershed. We first use wavelet analysis to research the law of precipitation of experimental watershed, and get some conclusions which the change of precipitation display the periodic return on 16 yearly, 8 yearly, 4 yearly scale, and the rainfall is decreasing.We use the advanced instruments to research the soil moisture. Through imitating the feature curve of soil moisture of different stand, we know the character of soil moisture of different stand, and through classifing to soil moisture, we calculate the effective value of soil moisture of different stand. The Robinia psedoaeacio is the mostly preventing drought tree.Through studying the relation between the growth of tree and soil moisture, we get that the water resources and heat resources are the dominant factors of restricting the growth of tree, especially the water resources. Growth of trees of suitable mixed forest is better than those of pure forest in the same condition. Biomass of different slope is different. Biomass of northward slope is apparently more than that southwardslope. The water use efficiency of stand is low in experimental watershed.Through studying the water-balance of root of different stand and comparing the quantity of impertation and expertation of water, we know that the variety of tree, slope situation, slope, and density are the dominant factors to the water-balance. We research the distribution of soil moisture on slope with geo-statistics. The vertical distribution of soil moisture can be classified three-layers in different stand. The change of season of soil moisture can be classified three-phase. At last, we provide the table of density of planting different variety of tree, and provide scientific basic for constructing the protective-forest on slope on Loess Plateau.