Han Min, Sun Yannan, Xu Shiguo
School of Electronic and Information Engineering, Dalian University of Technology, Dalian, 116023, China.
Environ Monit Assess. 2007 Apr;127(1-3):363-81. doi: 10.1007/s10661-006-9286-6. Epub 2006 Oct 21.
Zhalong National Nature Reserve in the northeast of China is a large wetland and a habitat of hundreds species of fauna and flora. The rare red-crowned crane is one kind of endangered birds in it. Recently, Zhalong wetland is shrinking and it encounters many problems including occasional fires, bad water quality, human activities, etc. In order to find out a proper way to protect and restore the wetland, this study, using a geographic information system, the global positioning system and remote sensing techniques, analyses the spatial characteristics of the changes in marsh landscape pattern and examines the driving factors for these changes. Data sources include 8 Landsat Thematic Mapper satellite images of Zhalong area in the period of 1986-2002 and the investigation information on site. Based on the analysis of changes of marsh area and annual precipitation during the 16 years, it is found that there is a close correlation between annual precipitation and marsh area. It means that climate is one of driving factors of marsh pattern changes. To understand influences of other kinds of land uses on marsh spatial distribution in Zhalong wetland, this paper analyses the relationship between marsh and different kinds of land uses, such as water surface, residential area, farm land, salina land and grass land, respectively. According to the patch analysis theory, a fragmental index and a fractal dimension of the marsh are calculated with perimeter-area method. The results indicate that the marsh pattern is affected by human activities significantly. In addition, the location alteration of marsh centroid point over the 16 years is studied. The movement trace of marsh centroid point is concerned with different hydrological situation in different areas of the wetland. In summary the characteristics of the marsh landscape pattern evolution during the 16 years are affected by multiple driving factors. The main driving factors are climate, human activities, distribution of other kinds of land uses and hydrological situation in different areas.
中国东北的扎龙国家级自然保护区是一片大型湿地，也是数百种动植物的栖息地。珍稀的丹顶鹤就是其中一种濒危鸟类。近年来，扎龙湿地不断萎缩，还面临着诸多问题，包括偶发火灾、水质恶劣、人类活动等。为了找到保护和恢复湿地的合适方法，本研究运用地理信息系统、全球定位系统和遥感技术，分析了沼泽景观格局变化的空间特征，并探究了这些变化的驱动因素。数据来源包括1986 - 2002年期间扎龙地区的8幅陆地卫星专题制图仪卫星图像以及实地调查信息。通过对16年间沼泽面积变化和年降水量的分析发现，年降水量与沼泽面积之间存在密切关联。这意味着气候是沼泽格局变化的驱动因素之一。为了解扎龙湿地其他土地利用类型对沼泽空间分布的影响，本文分别分析了沼泽与水面、居民区、农田、盐碱地和草地等不同土地利用类型之间的关系。根据斑块分析理论，采用周长 - 面积法计算了沼泽的破碎化指数和分形维数。结果表明，沼泽格局受人类活动影响显著。此外，还研究了16年间沼泽质心点的位置变化。沼泽质心点的移动轨迹与湿地不同区域的不同水文状况有关。综上所述，16年间沼泽景观格局演变特征受多种驱动因素影响。主要驱动因素包括气候、人类活动、其他土地利用类型分布以及不同区域的水文状况。
