Planning method of ecological restoration based on enlarging terrace and de-farming in the loess hilly-gully region:A case study of Yangou Catchment
黄土丘陵区"梯田退耕"生态重建规划方法--以燕沟流域为例

A core idea of enlarging terrace and de-farming (RTD) is "to carry out development itself by a definite external support",and its key contents are to rebuild terrace,to enlarge garden plots and to restore vegetation in the loess hilly-gully region.Based on the previous research results of the successful cases of small catchments,this paper discussed the planning principles of RTD ecological restoration,and put forward the planning method and its techno-flow by means of GIS spatial analysis.And then,the planning method was applied to Yangou catchment, and the result showed that it is practicable. The above discussed planning principles of RTD eco-environment restoration should include the actualization of the planning should be in a catchment or a village,the land use structure should be regulated by terrain gradient,the distance of rebuilt terraces and enlarged garden plots from a residential area should be less than 2km.The techno-flow of the planning method includes the following steps:(1)to digitize maps of terrain,land use,village boundary and residential area;(2)to match and attach those maps;(3)to pick up spatial data and confirm planning data;(4)to make sure the planning and distribution schemes;and (5)to analyze the planning results. The study results applied to Yangou catchment showed that the area of enlarged terraces is at least 295.06hm2,with 359.23hm2 of total basic farmland area,the area of enlarged garden plot is at least 4.61hm2,with 622.69hm2 of total area,and de-farmed slope farmland at least 410.35 hm2.After the land use structure being regulated,the forest cover rate is 48.87% and the permanent vegetation cover rate is about 75% in Yangou catchment.And in the agricultural development,the Yangou catchment can yield 1 645 tons of food supplies,9 340 tons of apples,and can feed 7 500 sheep every year.