摘要
选用不同年代的地形图、以及遥感图象数据等信息源,用地理信息系统以及景观指数分析方法对射阳湖湖沼环境的动态变化进行了初步研究。结果表明,射阳湖的面积逐年减少,从1958年到1974年,射阳湖的面积减少了153.245km2,年均递减9.578km2,这两个时期的年均面积递减率是最大的。景观指数分析表明射阳湖湖沼湿地的破碎化程度和空间异质性越来越高。大量水利工程的修建导致上游来水减少是射阳湖面积减小的主要原因,滩地围垦、水产养殖业以及居民地扩展等是其变化的主要因素。
The information sources, including topographical maps in the different time, remote sensing images, were selected to preliminarily investigate the dynamic variations of Sheyang lake in the past 76 years by means of GIS and landscape indices analysis methods. The results showed that it reduced 141.093 km2 from 1920 to 1958 in Sheyang lake , and the annual decrease rate of it was 3.713 km2. Area of Sheyang lake reduced 153.245 km2 from 1958 to 1974, and the annual decrease rate of it was 9.578 km2, which was the maximum in three periods of Sheyang lake reduced 143.514 km2 from 1974 to 1996, and the annual decrease rate of it was 6.52 km2. Compared with it in 1920, area of Sheyang lake in 1996 reduced 437.852 km2, which accounted for 38.1% of total area in 1920. Meanwile, marsh area continuously dramatically decreased in the past 76 years; but the change of water body area was fluctuant. It decreased from 1920 to 1958, afterward continuously increased because of the necessity of local economy development, many fishing ponds were dug in marshes or fertile agriculture land for fast development of aquaculture. While the area of natural lakes decreased. It was significantly decreased to 5.715 km2,5.448 km ,2.294 km2,respectively in lakes include Dazong lake, Wujin lake and Laizi lake from 1920 to 1958, There was no significant variation trend of nearly all natural lakes from 1958 to 1996.Several landscape indices, for example, patch quantity, average patch size and patch density, were introduced in this paper to explain the landscape change of lake and marsh environment in Sheyang lake. Patch quantity of water body is 16, 48, 60 and 188 from 1920 to 1996, respectively, average patch size 6.907, 2.057, 1.838 and 0.966, respectively, patch density 0.145, 0.486,0.544 and 1.036, respectively. These landscape indices showed that the patch quantity of water body became more and more, patch size smaller and smaller from 1920 to 1996. That is, water body became more and more fragmentized, higher and higher spatial heterogeneity
出处
《湿地科学》
CSCD
2003年第2期81-85,共5页
Wetland Science
基金
国家自然科学基金项目(40301013)
江苏省自然科学基金资助项目(BK2001041)
中国科学院知识创新工程重要方向性项目(KZCX3-SW-331)。
关键词
射阳湖
湖沼环境动态变化
遥感
地理信息系统
景观指数
Sheyang lake
dynamic variations of lake and marsh environment
rmote sensing
GIS
landscape indices
