Study On Spatial Variability Of Soil Moisture And Revegetation On Rare Earth Tailing Slopelands In South Of China

Southern Jiangx、northern Guangdong and western Fujian in southern China have rich rare earth resources, especially ion adsorption-type rare earth mines which are China’s unique. Since the1980s, China’s rare earth mines have been started large-scale development, but mining waste land management has not yet been given sufficient attention, where a large number of rare earth mines discarded cause serious soil and waste loss, which urgent need to strengthen governance. As the extreme degradation of land, the research of the ecological status and ecological restoration in mining wasteland should be strengthened.Rare earth backfilling materials are extremely barren, and of little clay content, and of weak fertilizer and water conservation capacity, so they have bad plant-growth conditions. In such venues, planting cultivation, the selected plants should have the characteristic of fast growth and resistance to drought and barren.Soil moisture of the slope is characteristic of spatial variability. The low moisture content is one of the limiting factors of vegetation recovery of mining abandoned tailing sites. Researching the spatial variability of water in the slope of rare earth tailings can play an important role in guiding the ecological recovery of such abandoned tailing sites. This research takes the rare earth tailings in Xiazhuang village as research object, In which the influence that aspect and slope position of the tailings make to moisture state is analyzed, and observational studies of vegetation recovery is conducted, thus the correlation between moisture and vegetation recovery is proved.1、Soil moisture of the slope is characteristic of spatial variability(1) The law of water content of slopes of rare earth backfilling materials along the direction of the slope length generally is:base of slope> middle slope> top of slope. The analysis shows that moisture content in the three slopes of the rare earth backfilling materials is of significant difference.(p＜0.01)(2) The law of water content of different aspects of the slopes of rare earth backfilling materials is:in original case, east slope＞south slope＞west slope; in slope treatment case:east slope＞western slope＞south slope. The analysis shows that moisture content in the different slopes of the rare earth backfilling materials is of significant difference.(p＜0.01)(3) Moisture of slopes in the rare earth backfilling materials is not only different in each position and aspect, but the difference between the different position and aspect, is also significant.2、Eragrostis curvula of the slope is characteristic of spatial variability.(1) In this study, the method of combining the field of cell cultivation and indoor potted is put to use, and the growth force, drought resistance, and barren degree of several plants are compared in the cultivation of Rare earth backfilling materials. Result shows that, the Eragrostis curvula for this study is the most appropriate.(2) Trends of the Eragrostis curvula biomass along the long direction of the slope shows:middle slope＞base of slope＞top of hill.(3) Change characteristics of the Eragrostis curvula in different slope are west-slope＞este-slope＞south-slopeIn this study, the spatial difference between water conditions and vegetation recovery of abandoned land is discussed, which will supply reference for further explore for the relation between the natural and geographical conditions and vegetation recovery of abandoned land, especially for the recovery of the wasteland in the rare earth backfilling materials.