环渤海湾不透水面时空格局变化及其景观生态效应研究

发布时间：2018-09-13 13:16

【摘要】：不透水面(Impervious Surface Area,ISA)是一种常见的人工建筑地表特征,经常被作为评价区域生态环境健康的重要指标,也被广泛的应用在区域城市扩张监测研究中。不透水面不仅对区域地表水—地下水循环、水文环境以及局部气候的有一定的影响,也在一定程度上加剧城市热岛效应和雨岛效应,进而影响整个区域生态系统的健康平衡。因此,开展对不透水面空间格局及其时间变化的相关性研究具有重要意义。遥感可以提供实时、观测范围大的卫星影像数据,中等分辨率的Landsat卫星影像以其自身的优势,已逐渐成为不透水面研究的重要数据源,新卫星Landsat8的成功运行及其搭载的传感器的改进也可为不透水面的相关研究提供最新的影像数据。渤海湾是我国北方经济发展重心,其地理位置特殊,海岸带生态系统脆弱,对人类活动敏感。随着沿海经济的发展以及港口工业的兴起等,该区域内不透水面的空间格局变化加快。掌握不透水面空间格局,揭示滩涂湿地、植被等资源与不透水面扩张之间的关系,对科学合理地推进渤海湾周边城市化进程和海岸保护提供参考依据。本研究在参考大量遥感影像分类和不透水面提取研究文献的基础上,采用最小噪声分离法(Minimum Noise Fraction Rotation,MNF)和支持向量机(Support Vector Machine,SVM)分类相结合的方法,利用Landsat 5卫星搭载的专题制图仪(Thematic Mapper,TM)传感器影像和Landsat8卫星搭载的陆地成像仪(Operational Land Imager,OLI)传感器影像,对环渤海湾内陆区域两期影像的不透水面进行自动提取,利用GIS空间分析功能,分析不透水面的空间格局和时间变化特征,研究不透水面扩张导致的景观格局变化、海域空间资源资源占用和植被资源损失等景观生态效应。本研究的创新点有:使用最新的OLI传感器影像提取环渤海湾不透水面现状,并从海岸区位角度分析不透水面分布及其扩张的海岸梯度效应;在提取过程中,对于大面积的盐碱地影响不透水面提取精度的问题,采用将盐碱地作为单独一类端元,与传统四端元模型相结合的方法,有效的去除大面积盐碱地,提高不透水面的提取精度。研究结果显示,基于MNF和SVM的不透水面提取方法具有较好的可操作性,2000年TM影像提取总精度为92.33%,kappa系数为0.80,2013年OLI影像的提取总精度为95.06%,kappa系数为0.90,提取精度满足研究需要;OLI影像在不透水面的细节上的表达更具优势,色彩丰富度提高,改善了TM影像校正后的过饱和现象。海岸线两侧陆域和海域以及内陆中心建成区是环渤海湾沿岸不透水面分布和扩张的重点区域,不透水面分布趋海化现象明显;不透水面现状特征呈大斑块、团状格局分布;不透水面的扩张占用了大量的滩涂等海域空间资源,其中,2013年研究区不透水面占用滩涂资源总量约为464.32km2;研究区植被覆盖减少与不透水面扩张之间在空间分布上并不具有完全的一致性,在城市建成区两者呈现明显的此消彼长现象,而农村地区该现象并不明显。未来将进一步结合已有研究成果,分析不透水面扩张对环渤海湾水质环境的影响等。
[Abstract]:Impervious Surface Area (ISA) is a common surface feature of man-made buildings. It is often used as an important index to evaluate the health of regional ecological environment and is widely used in monitoring regional urban expansion. Therefore, it is of great significance to study the correlation between the spatial pattern of impervious surface and its temporal changes. Remote sensing can provide real-time satellite image data with large observation range and medium resolution. Landsat 8 has become an important data source for impermeable surface research because of its own advantages. The successful operation of Landsat 8 and the improvement of its sensors can also provide the latest image data for impermeable surface research. With the development of coastal economy and the rise of port industry, the spatial pattern of impervious surface in this area has changed rapidly. To master the spatial pattern of impervious surface, reveal the relationship between the resources of beach wetland, vegetation and the expansion of impervious surface, and promote the cities around the Bohai Bay scientifically and rationally. Based on a large number of research papers on remote sensing image classification and impermeable surface extraction, this study combines Minimum Noise Fraction Rotation (MNF) with Support Vector Machine (SVM) classification and uses Landsat 5 satellite-borne special purpose. The TM sensor image and the OLI sensor image carried by Landsat 8 satellite are used to extract the impervious surface of the two phase images of the inland area around Bohai Bay automatically. The spatial pattern and temporal variation characteristics of impervious surface are analyzed by using the spatial analysis function of GIS. The innovations of this study are as follows: using the latest OLI sensor images to extract the current situation of impervious surface around the Bohai Bay, and analyzing the gradient effect of impervious surface distribution and its expansion from the perspective of coastal location. In the process of extracting water-tight surface from saline-alkali soil, saline-alkali soil was taken as a separate class of end-elements, which was combined with traditional four-end-element model to remove saline-alkali soil effectively and improve the extraction accuracy of impervious surface. The total accuracy of TM image extraction in 2000 was 92.33%, the kappa coefficient was 0.80, the total accuracy of OLI image extraction in 2013 was 95.06%, and the kappa coefficient was 0.90. The extraction accuracy meets the research needs. OLI image has more advantages in the details of impervious surface, and the color richness is improved, which improves the supersaturation of TM image after correction. Elephants. The land and sea areas on both sides of the coastline and the built-up area of the inland center are the key areas of the impervious surface distribution and expansion around the Bohai Bay. The impervious surface distribution tends to be sea-like obviously; the impervious surface present situation characteristic presents the big patch, the cluster pattern distribution; the impervious surface expansion occupies a large number of beach and other sea area spatial resources, among which, in 2013, the impervious surface distribution tends to be sea-like. The total amount of impermeable land resources occupied by the study area is about 464.32 km 2 in 1997. The spatial distribution of vegetation coverage reduction and impermeable land expansion in the study area is not entirely consistent. There is an obvious change between the two phenomena in urban built-up areas, but not in rural areas. The effects of impervious surface expansion on the water quality and environment in the Bohai Bay are analyzed.
【学位授予单位】：中国科学院烟台海岸带研究所
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：P237

【参考文献】