基于3S技术的东洞庭湖湿地植被的分布与适应性分析

利用2010年环境一号卫星影像提取东洞庭湖湿地植被分布图，依据同时期的MODIS13数据合成增强植被指数（EVI）年最大值图与年平均值图，结合东洞庭湖高程，讨论东洞庭湖湿地植被及其生物量空间分布，并从水文因素及植被生长特性等方面分析其原因，推论出芦苇与湖草等植被的最适宜生长区域.结果说明，东洞庭湖植被及其生物量分布与高程及水环境有很大的相关性，在高程30 m以上且远离水域区域，主要生长着对水分要求不高的防护林；芦苇适合生长在27 m高程以上且靠近水域的区域，湖草适合生长在高程为23~27 m间的区域.

The Spatial Distribution and Adaptability Analysis of Vegetation in East Dongting Lake Wetland Based on 3S Techniques

HJ 1A/1B satellite data in 2010 were used to extract wetland vegetation of East Dongting Lake. Based on the same period''s MODIS13 (Moderate Resolution Imaging Spectrometer) data production, the annual maximum value and average value of the EVI (Enhanced Vegetation Index) were synthesized. Vegetation spatial distribution and its biomass were discussed by combining the above indexes with the elevation figure of East Dongting Lake. Moreover, the most suitable growth area of vegetation was assessed from hydrological factors and vegetation growth characteristics, which will provide theoretical guidance for the protection of the vegetation diversity and the restoration and utilization of the vegetation resource in East Dongting Lake. All these proved that long water flooded time in the regions of low elevation was harmful to the growth of moss grasses. The results indicated that vegetation spatial distribution and its biomass had great correlation with the elevation and water environment in East Dongting. The shelter forests, whose water demand is not high, grow in the area more than 30m in height and away from the water, while reeds grow well in the area above 27m elevation and near waters, and moss grasses are suitable to grow in the regions ranging from 23m to 27 m.