太湖流域土地利用生态安全评价研究

发布时间：2018-01-17 22:06

本文关键词：太湖流域土地利用生态安全评价研究　出处：《华中师范大学》2015年硕士论文　论文类型：学位论文

【摘要】：太湖流域地处长江三角洲,地理位置优越,气候宜人,自然资源丰富,同全国其他地区相比经济更发达、人口更密集、城市化程度更高。但由于受到日益加剧的人类活动影响,太湖流域面临着水质污染、环境恶化、生态系统退化等一系列生态环境问题,生态安全受到威胁。社会经济活动与环境条件变化对土地利用履被景观格局有直接影响,也近一步影响到区域生态安全,故研究土地利用/覆被格局空间演变规律,并定量评价区域生态安全态势,对于促进区域土地资源可持续利用和生态、社会协调发展有重要理论和现实意义。因此本文以太湖流域为研究对象,在地理信息系统技术支持下,借助景观生态学理论和生态安全评价有关研究方法,系统分析研究区土地利用现状和景观格局空间演变规律,在建立不同尺度下太湖流域生态安全评价指标的基础上定量评价了太湖流域生态安全状况及聚集特征,主要研究结论如下：(1)太湖流域土地利用中以耕地所占比例最大,为35.38%,建设用地次之,为23.55%,未利用土地(包括荒地、裸地)最少,仅为1.8%。流域内耕地总体呈现东部多西部少的空间分布形态；林地主要集中于西南部,以湖州市、杭州市和无锡市等为主要集中城市；水域分布则以太湖为中心,呈现由东北向西南逐渐减少的空间分布形态；建设用地分布分散,大部分集中于太湖流域东部,且与耕地的分布呈一定交叠性,反映出流域内人类活动的空间特性和强度。草地、未利用地面积比例仅为4.42%,且零散分布。(2)从景观类型指数来看,太湖流域西南部和东部耕地景观斑块破碎度较大,形状不规则,而西北部和东南部耕地景观破碎度相对较小、斑块形状较规则；流域西南部林地景观斑块破碎度较大,且形状不规则,东部林地景观破碎度相对较小、形状较规则；太湖流域西北部水域景观斑块破碎度较大,斑块形状不规则；太湖流域东南部和北部建设用地景观破碎度较大,形状不规则,其余区域建设用地破碎度相对较小；草地、未利用土地斑块零星分布,破碎度较大,且密集区域形状不规则。(3)从景观总体水平指数来看,太湖流域景观类型丰富,各类景观呈均衡化分布趋势的区域主要包括西北部、湖州市的德清等区域；太湖流域边缘如杭州市的临安县、上海市东南部靠近黄浦江地区、以及太湖湖体区,景观类型呈现单一化趋势,少数优势景观类型的支配作用较大,景观破碎度较小,不同斑块类型的邻接概率较小。(4)以土地利用、景观格局及统计数据为基础,构建太湖流域市域和网格两个尺度下的生态安全评价指标体系,然后计算获取了太湖流域多尺度下的生态安全指数和生态安全等级。市域尺度上的生态安全情况以安全和较安全为主,另有少量—般安全和较不安全的市级行政区；生态安全状况最好的为湖州市,生态安全指数为0.7299,杭州市、镇江市为较安全状态,生态安全指数分别为0.6483、0.6157。而上海市、嘉兴市、南京市生态安全综合情况相对较差,均未超过0.45,生态安全等级为4级,为较不安全状态。总体看来,流域生态安全指数自西南向东逐渐降低。网格尺度上,生态安全指数最大值为0.7111,最小值为0.2807,结果数据基本符合正态分布；生态安全等级以较安全状态为主,状态较好的区域主要集中在流域北部,且基本相连；处于较不安全状态的主要是太湖湖体区。生态安全指数高值区与低值区的分布基本与市域尺度的评价结果趋同,且网格生态安全指数呈现空间集聚特性。
[Abstract]:Taihu basin is located in the Yangtze River Delta, geographical location, pleasant climate, abundant natural resources, compared with other areas in more developed economies, more densely populated city, higher degree. But due to the impact of human activities increasing, Taihu basin faces water pollution, deterioration of the environment, a series of ecological environment problems degraded ecosystem, ecological security is threatened. The changes of social economic activities and the environmental conditions of land use cover has a direct impact on the landscape pattern, also further affect the regional ecological security, so the study of land use / cover spatial pattern evolution, evaluation of regional ecological security situation and quantitative, for promoting regional sustainable utilization land resources and ecology, has important theoretical and practical significance to social harmonious development. Therefore this paper takes Taihu basin as the research object, in the geographic information system technology support, with the help of The research on the evaluation methods of landscape ecology and ecological security system, analysis of current situation and landscape evolution of the spatial pattern of land use in the study area, based on a different scale of ecological security of Taihu basin on the evaluation index of quantitative evaluation and accumulation characteristics of ecological security of Taihu basin, the main conclusions are as follows: (1) the land use in Taihu the cultivated land is the largest proportion, 35.38%, construction land of 23.55%, unused land (including land, bare land) at least, only 1.8%. of arable land basin shows the distribution of less space in East West; woodland mainly concentrated in the southwest, in Huzhou City, Hangzhou city and Wuxi city etc. as the main focus city; water distribution in Taihu as the center, decreasing gradually from the northeast to the southwest of the spatial distribution of construction land; distribution of concentrated in Taihu The eastern basin, and the distribution of cultivated land and forms a certain overlap, reflect the spatial characteristics and intensity of human activities in the river basin. Grassland, unused area proportion is only 4.42%, and scattered distribution. (2) from the landscape index of Taihu basin, southwest and east of farmland landscape patch fragmentation, shape the irregular, and the northwest and southeast of farmland landscape patch shape is relatively small, the southwest basin rules; forest landscape fragmentation is large, and the shape is irregular, the eastern woodland landscape fragmentation is relatively small, with regular shape; Taihu basin northwest water landscape fragmentation is larger, irregular patch shape; the construction of the southeast and north of the Taihu basin land landscape fragmentation, irregular shape, the area of construction land fragmentation is relatively small; grassland, unused land patches scattered distribution, fragmentation , and the dense regions of irregular shape. (3) from the overall level of landscape index, Taihu basin landscape types, landscape distribution equalization trend mainly distributed in Northwest Huzhou City Deqing area; Taihu basin edge such as Hangzhou City, Ling'an County, Southeast of Shanghai, near the Huangpu River area, and Taihu Lake area, the landscape types showed a single trend, a few dominant landscape types dominate the landscape fragmentation is larger, smaller, adjacent smaller probability of different patch types. (4) the land use and landscape pattern based on the statistical data, construct the evaluation index system of ecology security domain and grid in Taihu basin in two scale then, the calculation of ecological security index and ecological security level for Taihu basin scale. The ecological security situation on city scale in a safe and relatively safe, while a small amount of- The municipal administrative region as safe and less safe; the status of ecological security in Huzhou was the best city, the ecological security index of 0.7299, Hangzhou City, Zhenjiang City, is a relatively safe state, the ecological security index are 0.6483,0.6157. and Shanghai City, Jiaxing City, the comprehensive situation of ecological security in Nanjing city is relatively poor, no more than 0.45, the ecological the level of security for the 4, less safe state. Overall, ecological security index of river basin from the southwest to the east gradually decreased. The grid scale, the ecological security index of the maximum value is 0.7111, the minimum value is 0.2807, the data accord with normal distribution; ecological security level to a safe state, regional state better mainly concentrated in the northern basin, and connected; in relatively unsafe state is mainly the Taihu Lake area. The ecological security index of high value area and low value area distribution and city scale evaluation results The convergence of the grid ecological security index shows the characteristics of spatial agglomeration.

【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：F301.2;X826

【参考文献】