三江平原孤立湿地空间分布及其影响因素

以遥感影像为数据源,结合GIS技术,利用空间分析与统计方法对三江平原孤立湿地空间分布特征及影响因素进行定量分析。研究结果表明:孤立湿地的质心偏向西南,其椭圆的长轴方向为东北-西南方向,椭圆周长面积比大于全部湿地(沼泽湿地、河流湿地和湖泊湿地)椭圆周长面积比,分散性明显;孤立湿地的热点地区主要有3个,主要分布在受人为干扰影响较大的三江平原的中部、西北部和西南部;在自然因素影响下,孤立湿地于海拔高度51—54m、坡度1—3度、距离河流12—16km、河流阶地地貌部位处达到最大值;受人为因素的影响,孤立湿地主要分布在居民点、道路和保护区附近,与排水沟渠之间的关系是随着距离的增加,孤立湿地数量呈先增加后减少的趋势。三江平原孤立湿地空间分布是自然因素和人为因素综合作用的结果,人类活动对孤立湿地和非孤立湿地空间分布格局具有不同的影响,应加强对孤立湿地的保护。

Analysis of isolated wetland spatial distribution and factors influencing it in the Sanjiang Plain, China

We used spatial analysis and other statistical methods with remote sensing image data and GIS technology to analyze the spatial distribution characteristics, and factors that influence this distribution, of isolated wetlands in the Sanjiang Plain, China. The mean center of the isolated wetlands is in the southwest, the long axis of the area is northeast-southwest, and the perimeter-to-area ratio of the ellipse is greater than that of the whole wetland (marsh, riverine wetland, and lake wetland). There are three "hot spots" of wetlands-in the central, northwest, and southwest of the Sanjiang Plain-which are influenced by human disturbance. Under natural conditions, isolated wetlands range in altitude 51-54 m, grade 1-3 degrees, distance to a river 12-16 km and the site of river terraces reach maximum height. Influenced by human factors, isolated wetlands are mainly distributed in residential areas, roads, and protected areas, and the relationship between the isolated wetlands and the drainage ditches is increased with distance. The number of isolated wetlands increased and then decreased under human activity. The spatial distribution of isolated wetlands in the Sanjiang Plain is a result of both natural and anthropogenic factors, and the protection of the isolated wetlands should be strengthened.