【摘 要】
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The construction of the Three Gorges Reservoir and the resettlement project have caused increasing contradictions between human and land,and led to the deterioration of the ecological environment.In order to ameliorate ecological environment of the Three
【机 构】
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School of Geographical Sciences,Southwest University,Chongqing 400715,China
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The construction of the Three Gorges Reservoir and the resettlement project have caused increasing contradictions between human and land,and led to the deterioration of the ecological environment.In order to ameliorate ecological environment of the Three Gorges Area,the government carried out several ecological restoration projects to improve the vegetation coverage from 1990s.This paper aims to quantitatively analyze the impact of ecological projects on the vegetation in the Three Gorges Area of Chongqing,China.Landsat and MODIS data from 1992 to 2015 were used to estimate vegetation coverage.In addition,the land cover data of the European Space Agency (ESA) was used to explore the impact of ecological projects on land cover change.The cropland accounted for about 62％ and the forestland accounted for about 34％ of the total area.There was more than 90％ of the study area covered with high or very high vegetation coverage.From 1992 to 2015,a total of 272.7 km2 croplands were converted into forestland in the Ecological Migration Project (EMP),795.6 km2 in the Grain for Green Project (GGP),and 13.77 km2 in the Ecological Restoration Zone Project (ERZP).Among the three projects,the GGP was the most powerful measure,with a contribution rate of 1.6％.The implementation of the ecological projects improved vegetation coverage,which indicated that the ecological projects measures were effective in ecological restoration.
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