基于RS和GIS的长江中下游湖泊湿地景观动态变化研究

发布时间：2018-06-06 10:53

本文选题：湖泊湿地 + 景观格局　；参考：《华中师范大学》2013年硕士论文

【摘要】：湿地科学的研究是从湖泊学和沼泽学发展而来的,对湿地进行研究最早可以追溯到17世纪。经过300多年的不断发展,湿地科学已由最初的萌芽状态演变为科学框架构筑阶段,现已成为国内诸多外专家学者所关注的热点研究领域。长江中下游地区是中国淡水湖泊分布最集中的区域之一,湖泊湿地景观对该区域的发展具有重要意义,但是近几十年来人类活动与河流泥沙淤积共同制约、影响着湖区的演变,围湖造田、河流上游乱砍滥伐导致水土流失加剧,湖泊泥沙大量淤积,不断加速着该地区淡水湖泊的衰亡,湖泊水体面积急剧缩小,泥滩、草滩、芦苇滩地等景观面积逐渐增多,再加上城市化的迅速发展,人工地表和建设用地也迅速增加,湖区景观及其功能发生了巨大的变化。本文利用RS和GIS对长江中下游地区湿地景观动态变化进行研究,首先对研究区1984年至2012年近三十年中的Landsat TM/ETM、MODIS卫星遥感影像以及欧空局ENVISAT卫星拍摄的2009年遥感影像数据的湿地景观进行分析,然后对遥感影像采取分类处理的措施,获取研究区域内各年份相应的湿地景观基本参数,同时结合Google Earth和已收集到的土地利用类型图在ArcGIS中制作各年份的土地利用类型图,通过一系列景观格局指数例如：PLAND、LSI、LPI、CONHESION、 SHDI、SHEI等对景观格局进行分析,探讨长江中下游鄱阳湖、洞庭湖、太湖湖区湿地以及土地利用类型的动态变化规律,同时探讨景观格局变化的原因,得出结论如下： 1、通过对长江中下游地区三大淡水湖泊湿地景观的格局指数分析发现太湖由于地理位置和社会经济发展水平较高的因素使得其与鄱阳湖和洞庭湖在景观格局指数变化趋势略有不同。 2、鄱阳湖、洞庭湖、太湖湖区湿地景观面积呈下降趋势,其中耕地和水体减少最为明显,耕地的斑块个数逐渐降低,最大斑块指数逐渐增大,耕地逐渐转变为大斑块,表明人类活动对景观变化有重要作用。 3、在人类活动对湿地景观的影响上本文发现,对于自然湿地景观(泥滩地、草滩地、芦苇滩地),人类活动一定程度上增加了景观的破碎程度,降低了均匀度；但是在人类参与较多的耕地方面,降低了破碎程度,增加了景观的均匀度。 4、通过经济发达的太湖地区和欠发达的鄱阳湖、洞庭湖湖区对比发现,经济发达的地区近20年来建筑用地面积剧增,而以水体为主的,包括泥滩地、草滩地、芦苇滩地在内的自然湿地景观面积不同程度的降低；而欠发达的湖区由于城市化进程,建筑用地也在增加,但是增幅较小,自然湿地景观变化趋势除了水体其他皆与太湖湖区相反。 5、通过对三大淡水湖湖区的研究可以一定程度上推断出整个长江中下游地区湖泊湿地景观的演变情况——水体、耕地面积呈下降趋势；在经济发达地区自然湿地景观近20年呈下降趋势,欠发达地区呈略增趋势；由于城市化进程和社会经济的发展,建设用地面积呈上升趋势。 6、湿地演替是景观自然演变的重要原因,随着泥沙大量淤积,水体外缘地区依次会出现泥滩地、草滩地、芦苇滩地最终会转变为森林湿地。 7、泥沙淤积是加剧湖区景观转变的原因之一,尤其是水体景观的变化。大量植物又会加速泥沙的淤积,泥沙淤积又利于湿地演替的进行,二者形成恶性循环。 8、围湖造田和退耕还湖是影响湖区景观变化的主要原因。通过景观格局指数分析,可知人类活动对水体周围的景观变化有重要影响,尤其是耕地、水体以及建设用地的变化。
[Abstract]:The research of wetland science is developed from lakes and swamps. The research on wetlands can be traced back to seventeenth Century. After more than 300 years of continuous development, the wetland science has evolved from the initial bud to the construction stage of the scientific framework. It has now become a hot research field for many foreign experts and scholars in China. The downstream area is one of the most concentrated areas in China's freshwater lakes. The landscape of the lake wetland is of great significance to the development of the region. However, in the last few decades, human activities and sediment deposition have influenced the evolution of the lake area. The area of freshwater lakes in this area has been accelerated, the area of lake water is shrinking rapidly, the landscape area of the mudflats, the beach and the reed beach land are increasing gradually, and the rapid development of the urbanization, the rapid increase of the artificial surface and the construction land, and the great changes in the landscape and its function of the lake area.
In this paper, the dynamic changes of wetland landscape in the middle and lower reaches of the Yangtze River are studied by RS and GIS. First, the wetland landscape of Landsat TM/ETM, MODIS satellite remote sensing image and ESA ENVISAT satellite from 1984 to 2012 is analyzed, and then the classification of remote sensing images is taken. The basic parameters of the wetland landscape in each year of the study area were obtained. At the same time, Google Earth and the collected land use type map were used to make the land use types of each year in ArcGIS, and the landscape pattern was analyzed by a series of landscape patterns, such as PLAND, LSI, LPI, CONHESION, SHDI, SHEI and so on. The dynamic changes of the wetland and land use types in the middle and lower reaches of the Yangtze River in Poyang Lake, Dongting Lake, Taihu Lake area and the land use types are discussed. The reasons for the change of landscape pattern are discussed. The conclusions are as follows:
1, through the analysis of the landscape pattern index of the three major freshwater lakes in the middle and lower reaches of the Yangtze River, it is found that Taihu is slightly different from Poyang Lake and Dongting Lake in the landscape pattern index because of the high level of geographical location and the level of social and economic development.
2, the wetland landscape area of Poyang Lake, Dongting Lake and Taihu Lake District showed a decline trend, in which the decrease of cultivated land and water body was most obvious, the number of cultivated land patches gradually decreased, the maximum plaque index gradually increased, and the cultivated land gradually changed into large patch, indicating that human activities had an important role in landscape change.
3, in the impact of human activities on wetland landscape, this paper found that for natural wetland landscape (mudflat land, beach land, reed beach land), human activities to a certain extent increase the degree of fragmentation of landscape, reduce the uniformity of the landscape, but in the human participation in more arable land, reduce the degree of fragmentation, increase the evenness of the landscape.
4, through the economically developed Taihu area and the underdeveloped Poyang Lake, the contrast of the lake area of the Dongting Lake found that the area of the construction land has increased dramatically in the economically developed areas in the last 20 years, while the natural wetland landscape area, including the mudflat land, the beach land and the reed beach land, is not in the same degree, while the underdeveloped Lake area is urbanized. In the process, construction land is also increasing, but the increase is relatively small. The change trend of natural wetland landscape is contrary to that of Taihu Lake area except for other water bodies.
5, through the study of the three major freshwater lakes and lakes, we can deduce the evolution of the lake wetland landscape in the middle and lower reaches of the Yangtze River to a certain extent - the water body, the area of arable land shows a downward trend; the natural wetland landscape in the economically developed areas has declined in nearly 20 years, and the underdeveloped areas are slightly increasing; due to the urbanization process and society. With the development of economy, the area of construction land is on the rise.
6, the succession of the wetland is an important reason for the natural evolution of the landscape. With the accumulation of sediment, the mudflat land will appear in the outer edge of the water body. The beach land and the reed beach land will eventually turn into the forest wetland.
7, siltation is one of the reasons that aggravates the landscape transformation in the lake area, especially the changes in the water landscape. A large number of plants will accelerate the siltation of the sediment, and the siltation is also conducive to the succession of the wetland, and the two forms a vicious circle.
8, the main reason for the landscape change in the lake area is to make farmland and return the farmland to the lake. Through the analysis of landscape pattern index, we can see that human activities have an important influence on the landscape change around the water body, especially the changes of cultivated land, water body and construction land.
【学位授予单位】：华中师范大学
【学位级别】：硕士
【学位授予年份】：2013
【分类号】：P208;P237;P901

【参考文献】