A Research On The Ecological Environment Quality Evaluation In Bashang Area Based On RS&GIS

Located in north Hebei Province and the southern margin of Mongolia Plateau,Bashang area is a state key ecological function conservation area–Otindag EcologicalFunction Conservation Area of Desertification Prevention and Control, and also anecologically vulnerable area. However, due to a combined factor of both nature and humanactivities, the eco-environment there is negatively influenced by grassland desertification,swamp degradation and overexploitation.Based on remote sensing (RS) and geographical information system (GIS) as well asthe relevant theories and technologies, the present thesis took the remote sensing image ofLandSat-5TM and environmental statistical data as the primary data source and referredto Technical Criterion for Eco-environmental Status Evaluation for the evaluationstandards with combinations of the interpretation signs in the research area. Thehigh-accuracy land-use-and-cover map of Bashang area was obtained through combiningautomatic computer interpretation and manual field verification. And it worked out theoverall ecological index through method of weighted mean to make a quantitativeevaluation of the eco-environmental quality in Bashang area nearly10years. And in thelight of the evaluation results, the contributing factors influencing environment changeswere discussed, and some countermeasures and suggestions were proposed to improveeco-environmental quality.The primary conclusions of the thesis are as follows:1) By combining RS and GIS for the first time, the research offered an evaluation andanalysis of the eco-environmental quality in Bashang area, which would contribute ascientific basis and support in regional economy development and environmentconservation in this area.2) Through analyzing and summarizing the regional features in the research area andrelevant theories in eco-environmental quality evaluation, the research selected someinfluencing factors in eco-environmental quality including biological abundance,vegetation coverage, water system density, soil erosion, pollutant emission intensity, andother relevant indexes, so that an eco-environmental quality evaluation index systemsuitable for the research area was established.3) According to the changes in land use and cover in Bashang, there has been a continuous decrease in area of forest land, grassland and water, while a slight increase infarmland area and a significant increase in urban construction land area there. All theabove changes indicate that changes of the eco-environmental pattern in the research areawill be increasingly notable due to the human intervention in living and manufacturing.4) The evaluation results of eco-environmental quality showed that Weichang andFengning, which were evaluated as good in eco-environmental quality, own acomparatively high vegetation coverage rate and rich biological diversity, and thatZhangbei, Guyuan, Kangbao and Shangyi, which were evaluated as average ineco-environmental quality, have a medium vegetation coverage rate and biologicaldiversity.5) According to the driving influence analysis made from aspects of nature, humanityand biology, the leading driving factors of eco-environmental changes in the research areaare humanity ones, especially population growth, agricultural production, unreasonableexploitation and so forth.