甘肃省生态环境质量评价指标体系及十年变化趋势研究

发布时间：2018-06-08 08:30

本文选题：生态环境质量评价指标 + 十年变化　；参考：《兰州大学》2015年硕士论文

【摘要】：生态环境与人类活动息息相关,是人类赖以生存的基础,它不仅为人类提供了生存环境,也为人类社会提供了各种物质需求。因此,生态环境的好坏直接决定了人类的福祉。本研究基于RS和GIS技术,对甘肃省2000-2010年的生态环境质量评价指标体系和10年间生态质量变化趋势进行了研究,得出如下结果。1)甘肃省各市州行政区域内土地利用类型的空间分布特征与时空变化特征均具有不均衡性。随着经济的发展和人民生活水平的提高,城镇居民用地和农村居民用地在不断的增加,而这两者的主要演变途径来自于草地和和耕地。因为国家政策方面的因素,甘肃省许多地区开始采取退耕还林还草工程,因而使得甘肃省的草地、农村居民用地、城镇居民用地以及未利用地等土地利用类型之间呈现出趋于一个动态平衡的状况。2)甘肃省2000-2010年植被变化,各个等级之间转换互有正负,但整体正向变化略大于负向变化：植被覆盖由差变好,一级和二级植被的转入均大于转出,说明研究区优等植被面积得到了提高。三级植被面积有所减少,主要转出为二级植被,认为该区植被得到较好治理。四级和五级之间互有转换,劣等覆盖植被转好后又变坏,但总体四级植被的破坏大于治理。总体上,十年期间甘肃省植被覆盖呈现向优良和低等植被覆盖两极变化的趋势。3)甘肃省土壤侵蚀状况很严重,2000、2005和2010年甘肃省土壤侵蚀(不含无明显侵蚀)面积分别为24872.9 km2、27503.6 km2和28000.8 km2,主要侵蚀强度为轻度和中度侵蚀；不同地区土壤侵蚀空间差异性大,主要侵蚀地区分布在甘肃省南部地区,降水量的分布不均、土地利用类型和地貌类型的变化是造成这种差异的主要原因。林地的土壤侵蚀面积最大,草地次之,均为甘肃省主要侵蚀地带。陇南山地、甘南高原和陇中黄土高原是土壤侵蚀的主要侵蚀地貌类型；除了降水量分布不均、土地利用类型和地貌类型的变化外,人类对生态环境的不合理利用也是造成土壤侵蚀的另一重要原因。4)2000年至2010年全省市域生态环境质量状况指数变化幅度在-0.61—-2.23之间,兰州市生态环境略微变差,定西市、天水市生态环境略微变好,其余市州均属于无明显变化。
[Abstract]:Ecological environment is closely related to human activities and is the basis of human survival. It not only provides the living environment for human beings, but also provides various material needs for human society. Therefore, the quality of the ecological environment directly determines the well-being of human beings. Based on RS and GIS technology, the evaluation index system of ecological environment quality in Gansu Province from 2000 to 2010 and the change trend of ecological quality in 10 years were studied. The results are as follows: (1) the spatial distribution and spatiotemporal variation of land use types in the administrative regions of cities and states in Gansu Province are unbalanced. With the development of economy and the improvement of people's living standard, the land used by urban residents and rural residents is increasing, and the main ways of their evolution come from grassland and cultivated land. As a result of national policy factors, many areas in Gansu Province began to take the project of returning farmland to forests and grassland, thus making grasslands and land for rural residents in Gansu Province. Urban residents' land use and unused land use types showed a dynamic balance. 2) the vegetation changes in Gansu Province from 2000 to 2010, the conversion between different grades has positive or negative. But the overall positive change is a little larger than the negative change: the vegetation cover is changed from difference to better, and the first and second grade vegetation is larger than the transition out, which indicates that the superior vegetation area has been improved in the study area. The area of the third grade vegetation has been reduced, which is mainly transferred to the second grade vegetation, and it is considered that the vegetation in this area is well managed. There is mutual conversion between grade four and grade five, and the damage of the vegetation of grade four is greater than that of management, but the damage of the vegetation of grade four is bigger than that of the control. In general, The soil erosion in Gansu Province is very serious in 2000.2005 and 2010, the area of soil erosion in Gansu Province is 24872.9 km ~ 2 ~ (2 +) 27503.6, respectively. Km2 and 28000.8 km ~ 2, the main erosion intensity was mild and moderate erosion; The spatial difference of soil erosion in different areas is great. The main erosion areas are distributed in the southern part of Gansu Province. The distribution of precipitation is uneven. The change of land use type and geomorphology type is the main reason for this difference. The soil erosion area was the largest in woodland, followed by grassland, which was the main erosion zone in Gansu province. The main erosion geomorphological types of soil erosion are Longnan Mountain, Gannan Plateau and Longzhong Loess Plateau, except for the uneven distribution of precipitation, the change of land use type and geomorphologic type. The irrational use of ecological environment is another important cause of soil erosion. 4) from 2000 to 2010, the change range of ecological environment quality index of the whole province is between -0.61-2.23, the ecological environment of Lanzhou City is slightly worse, Dingxi City, Tianshui city ecological environment improved slightly, the rest of the city state belong to no obvious change.
【学位授予单位】：兰州大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：X821

【参考文献】