Study On Herbs And Their Utilization Mould In Different Regions In Loess Plateau

Loess Plateau (LP) has degraded into a barren and fragile Plateau with crisscross network of gullies and serious soil erosion. The starting of the engineering of Returning Farmland on Hills into Forest and Grassland (RFHFG) is bringing new chances and new challenges to Rehabilitation of Ecological Environment (REE) in LP.If the soil erosion and other ecological crisises is effectively brought under control, it will be of great immediate and permanent significance to the sustainable development of economy and society in Lp and in the areas of the lower reaches of Yellow River.The thesis summarized the main problem in REE, the law of vegetation's evolution and grassland resources as well as their district characteristics in LP. Also dividing LP into different Climate-terrain-geomorphy (CTG) regions and Topography Position Types (TPT) for grass growing. Based above, selecting the major of suitable grass species and putting forward to their utilization patterns in different areas.The main conclusions of the study are as follows:There are such problems in REE in LP as single plant varieties, overlooking to develop and use .native trees and herbs, simple and similar community structures, more proportion of economic forest and lawn as well as neglecting ecological benefits, also devoting too much attention to artificial restoration and rehabilition measure but too little by itself, and undetermined matching model of trees and grasses for RFHFG.Native vegetation in LP distributes in zone and nonzone, but with less and less rainfall, it becomes more and more xeric. Grassland resources in Lp fall into pratum steppe (PS), typical steppe (TS) and desert steppe (DS). Mid-xeric grass and sage dominate in PS, xeric grass and composite herbs in TS and xeric grass with some sage, thorny undershrub and semi.-frutex in DS.According to the division of the climate zone and geomorphy together with their features, LP are cut into eleven CTG regions such as LP Gullied Aera (LPGA) in Jinshaan in Warm Temperate Zone (WTZ) and Subhumid Climate Zone, and so on.LP shows itself as all kinds of TPT in the light of the position of terrain and the slope situation: Top of Liang Mao, Northern (Sourthern) slope of Liang Mao, Northern (Southern) slope of Gully, cover of Mesa, Northern (Southern) slope of Mesa and bottom of Gully etc.After studying thoroughly both the natural and artificial communities of plants, here are 9 types for arranging herbs concluded like timber forest mixed grass pattern and so on.On the basis of adptability of herbs and divisions of TPT, this paper established and conformed 34 grass utilization moulds in LP, here several were taken for example: eco-economy mould on cover of mesa, orchard-grass mould on level terrace on south slope of mesa, intercropping or rotating between grass and crops on north slope of mesa, farmland protective belt mould in hilly and gully, and so on.