【作者】 傅丽华；

【导师】 谢炳庚；

【作者基本信息】 湖南师范大学 ， 自然地理学， 2012， 博士

【摘要】 在快速城市化进程中,针对区域土地利用结构与功能的变化,如何有效调控土地利用生态风险,实现生态、经济、社会可持续发展是一个亟需解决的难题。本研究以长株潭核心区为研究对象,运用地理学、景观生态学、管理学、数学与计算机科学等多学科的方法与技术,依据研究区近20年来区域土地利用变化的尺度特征及生态风险作用驱动因子的分析,以景观结构及功能变化为切入点,对不合理的土地利用方式导致的土地利用结构变化及功能退化等引起的生态风险进行识别,构建基于景观生态学的风险评价指标体系和评价模型,开展不同尺度的土地利用生态风险评价,并以评价结果为依据,从调控目标、调控重点、调控尺度选择、调控行为决策与调控策略等方面提出如何有效实施土地利用生态风险调控。主要内容及结论如下：1.土地利用变化特征尺度分析根据长株潭核心区1989～2008年4期遥感影像数据资料,提取区域土地利用变化数据,以湘江样带为典型研究区,运用小波分析方法进行特征尺度检测。结果表明：长株潭核心区不同部位的特征尺度选择不是唯一的,长株潭城市群核心区土地利用变化具有多尺度敏感性,不同研究区域或研究部位的土地利用及景观格局变化对特征尺度选择有一定影响。不同土地利用及景观类型具有不同的尺度特征,城市边缘区的特征尺度值最小但景观敏感性最强,宜选择1980m左右的分析粒径；城市建成区特征尺度值最大,宜选择3300m左右的分析粒径,其景观敏感性最差。2.土地利用生态风险驱动因子及作用机理分析土地利用结构及功能变化是导致长株潭核心区土地利用生态风险的主要原因。在分析土地利用变化社会驱动因子作用的基础上,研究景观结构特征及格局变化的生态学特征,开展景观敏感性分析及生态系统服务价值评估,以更好的把握生态风险驱动因子作用的方式及过程。研究表明,社会经济因子是长株潭核心区土地利用生态风险作用的主导驱动因子,建设用地变化与GDP变化具有一致性；耕地与草地的景观敏感性最强,其次是林地和水域,建设用地及未利用地的景观敏感性最差。3.土地利用生态风险评价及特征分析根据对研究区土地利用变化及生态风险驱动因子作用的分析,结合景观生态系统服务功能价值,建立基于“源”与“汇”景观结构的土地利用生态风险评价指标体系及评价模型。结果表明,城市建成区土地利用生态风险高于其他区域,长沙市区整体风险值最高,较高风险及高风险区分布最广,湘潭次之,株洲市区整体土地利用生态风险最低。长株潭核心区土地利用生态风险均表现出即由一般风险区向中风险区,或者是由一般风险区向较高风险区发展的过渡性特点,低风险分布区域呈现零散分布,区域土地利用生态风险调控的压力较大。评价单元大小对评价结果的准确性有一定的影响,比较10km×10km及2km×2km粒径两种评价单元的分析结果,后者是更适合的城市群土地利用生态风险评价单元。4.土地利用生态风险调控结合对土地利用生态风险因子作用分析,以生态风险评价结果及风险指数变化规律为依据,确定不同变化情景的风险调控目标与调控重点,探讨土地利用生态风险的最佳时间、空间及功能调控尺度选择,并根据调控行为主体系统的特点,从微观层面开展了基于多智能体模拟(ABM)方法的土地利用风险调控行为模拟与决策,并提出了不同土地利用生态风险水平下的多种调控手段与调控策略。更多还原

【Abstract】 It is an urgent task to explore a good way to efficiently regulate land-use ecological risk in rapid urbanization within the concern of regional landuse structure and function changes to achieve ecological, economic and social sustainable development. With the aid of the research methods and technologies in such fields as geography, landscape ecology, management, mathematics&computer science, the dissertation, selecting Changsha-Zhuzhou-Xiangtan (abbr. C-Z-T) core area as the case, analyses its20-odd-year scale characteristics in landuse changes and factors of driving forces on ecological risks from the perspective of landscape structure and function changes to mark the signs and hints of such risks as landuse structure changes and function deterioration caused by improper landuse, attempts to establish a landscape-ecology-based risk evaluation index system and model to make assessment of landuse ecological risks at different scales and finally, based on the assessment results, puts forward how to efficiently regulate landuse ecological risks from such aspects as regulation objectives, focuses, scale selection, decision-making and strategies.The major results are listed as follows.1. Scale analysis of characteristics land-use changeThe scale analysis of land-use change characteristics from a wavelet analysis on typical transect line of the belt along the Xiangjiang River as the typical land-use region on the basis of the data of land-use change extracted from the remote sensing image data in four periods from1989to2008shows ⅰ) that the different degrees of sensitivity of each quarter of the C-Z-T core area to scale change determine their selection in land-use characteristic scale, ⅱ) that the characteristics scale selection varies as the land-use and landscape structure in different parts change, ⅲ) different land-use and landscape patterns have different scale characteristics, and ⅳ) that the value of scale characteristics is inversely proportional to the landscape sensitivity, which is supported by the results ⅰ) the quarter around the city centre has the highest value but the weakest sensitivity to scale change, thus about3,300m parcel analysis being the most appropriate and ii) the urban fringe quarter has the lowest value but the strongest sensitivity to scale change, thus about1,980m parcel analysis being the most appropriate.2. Analysis of driving factors and mechanism of land-use ecological riskIts changes of land-use structure and function are the major reason for the area’s land-use ecological risk. On the basis of the analysis of the driving factors of land-use change, the ecological characteristics of landscape structure and pattern change have been explored and an assessment has been made on the service value in ecosystem to better comprehend the factors’ driving process. The research shows ⅰ) that the socio-economic factor is the dominant driving factor of land-use ecological risk in the area, ⅱ) that the area of construction land increases with the GDP, and ⅲ) that arable land and grassland have the strongest sensitivity, woodland and water the weaker, and construction land and idle land the weakest.3. LUER assessment and characteristics analysisOn the basis of the combination of the analysis of the area’s land-use change and its ecological risk driving factors, an assessment indicator and its model have been established for the source-and-sink landscape. As the results show, land-use ecological risk in the built-up urban area is higher than other areas. The overall risk value of urban districts in Changsha, which has a largest distribution of higher risk areas and highest risk areas, ranks the highest, that in Xiangtan the second and that in Zhuzhou the last. The land-use ecological risk in the core area of Changsha-Zhuzhou-Xiangtan grows from the normal level to the medium level or even to the relatively high level. Low-risk areas scatter, which exerts much pressure on ecological risk regulation and control. The measurement of assessment units also influences the accuracy of assessment results. A2km×2km unit, compared with a10km×10km unit, is more suitable for land-use ecological risk assessment of urban agglomeration.4. land-use ecological risk regulation and controlOn the basis of the analysis of land-use ecological risk factors, the ecological risk assessment results and the rule of risk indicator change, the objectives and focuses of risk regulation and control are set to find the proper time, space and scale for function regulation and control of land-use ecological risk. With the characteristics of the main regulation and control system into consideration, Agent-Based Modeling (ABM) is adopted in micro-level action simulation and decision of land-use risk regulation and control and a variety of regulation and control means are proposed for multi-level land-use ecological risk.更多还原