The Analysis On Ecological Effect Of Land Use Change In Poverty Regions Surrounding Beijing And Tianjin Based On Converting Cultivated Land Back To Forest Or Grassland

The Region surrounding Beijing and Tianjin, with the important location, are the ecological defense of Beijing and Tianjin. But as the center of Regions surrounding Beijing and Tianjin, the two metropolises, Beijing and Tianjin, can not do as what Shanghai and Guangzhou have done to lead their surrounding area to the prosperity, on the contrary, there is a poverty belt existing in this region. The existence of the poverty belt influences the urban image of Beijing and Tianjin, but what is more important is to damage the ecological maintenance of the two cities. In 2002 the project of converting cultivated land back to forest and grassland was fully developed in Hebei Province, and the Region surrounding Beijing and Tianjin is the key area. The conversion of cultivated land leads to the area decrease of cropland and the area increase of forest or grassland directly, and the area change can result in the change of ecosystem service value consequentially. This dissertation takes the poverty region around Beijing and Tianjin as study area and tries to analysis quantificationally the relationship between land use/cover change and the change of ecological service value, discuss the construction of ecological compensation mechanism, and then proposes some countermeasures to promote the coordinated development of Beijing, Tianjin and their surrounding area. It is of great importance to strengthen the achievement of conversion of cultivated land and alleviate poverty situation of Region surrounding Beijing and Tianjin, and to construct the double-win regional relationship.Based on the introduction of background of topic selection and the study significance, this dissertation firstly identifies the study region, 31 poverty-stricken counties of 4 cites around Beijing and Tianjin, and the study time interval, from 2001 to 2007; then introduces the situation of cultivated land conversion back to forest or grassland and its ecological effect. The main body of this dissertation consists of three parts described as follows.The first part analyses the extent and rate of land use change during the period of cultivated land conversion, and then canonical correlation analysis is conducted between the conversion area of cultivated land and land use change in study area. The result shows significant correlations.The second part studies the ecological service value change of study region with the background of the conversion of cultivated land. The study result indicates the increase of about 54×108 Yuan RMB in ecological service value is achieved during the study interval. There are significantly positive correlations between this service value increase and the increase of forest land and reduction of unused land, and significantly negative correlations between this service value increase and the area decrease of cropland/grassland.The third part studies the ecological compensation. In this part the relationship between compensation subjects is identified and the compensation pattern is determined. And then this part discusses the standard of based on the project of cultivated land conversion, reasonable land use, and the distributive justice of environmental right and obligation.The dissertation finally proposes suggestions on the achievement maintenance of plowland's conversion, the regional relationship of environmental right and obligation, and the construction of ecological compensation mechanism.