Research In Vegetation Restoration And Soil Remediation Of Grain For Green

Since a long time, large areas of land reclamation, overgrazing and deforestation have been causing a severe damage of the earth's surface and vegetation. Those phenomenons such as soil erosion, desertification and hostile climate are becoming serious day by day, and have caused a great harm to the national economy and social development. Thus the Party Central Committee and the State Council have made a historic decision from the overall interests of society sustainable development and the interests of state and the nation to return farmland to forest and grass.With the implementation of Grain for Green Project, the vegetation has been established and restored; the soil have been restored; the soil erosion have been under controlled and the ecological environment have been improved. This thesis take the Qingyang municipality Gansu Province as an example, through the on-the-spot investigation and the laboratory experiment, fitting various kinds of empirical datum and the satellite remote sensing data, contrasting and analyzing functions and effects of different patterns of plant to restore the vegetation, to improve the structure of soil and to enhance the aspect of soil fertility ability, this thesis provides a scientific basis for the effect evaluation of the return farmland to forest and grass project. The findings are as follows:1. The vegetation has been restored and the ecological environment has been improvedWith the implementation of the Grain for Green Project, within 7 years, 2406km~2 woodland area has increased, the forest coverage has increased 8.8%, and the farmland asylum rate has achieved 40.1% of the whole Qingyang City. Since substantial farmland on steep slopes and the desertification soil return to green, the situation of East Gansu's soil erosion has been prevented effectively, and the tendency of sandstorm spread of East Longdong has been controlled, thus the ecological environment has been improved noticeably. The erosion module of the soil erosion area, by the former 5000-6000t/a · km~2 , now reduced to the 2000-4000t/a · km~2 ; and the annual frequency of disastrous climates, has markedly decreased.2 The physical nature of soil has been improved...