基于物种重要值和土壤水分的草原群落边界判定

对河北沽源草地生态系统野外观测研究实验站外不同区域的草原进行调查,统计其各物种重要值,并测定土壤水分,利用游动分割窗技术判定群落边界,以期为草原景观界面判定提供新思路。结果表明:基于物种重要值的欧式平方距离(SED)峰值分析发现,窗口大小为12个及12个以上样地单位时,SED峰值曲线趋于稳定,能较好的反映地上植被群落的分布格局。峰值图上出现4个明显的波峰,依据变化幅度可以判定2个是急变性过渡带,2个是渐变性过渡带。水分与群落分布的格局具有一定相关性,群落分布格局对土壤水分变化做出响应,并呈现一定的滞后性。试验结果验证了游动分割窗技术在草原景观界面判定的可行性。

Determine the Boundaries of Grassland Communities Based on Species Important Value and Soil Moisture content

The different areas of grassland in Hebei Guyuan grassland ecosystem experimental station were observed to investigate the important value of each species and soil moisture content.The boundaries of grassland communities were determined by moving split-window technique.Results showed that the curve of SED peak were in stable status when window size is more than 12 plots and 12 units better reflecting the distribution patterns of above-ground vegetation communities.Four distinct peaks were observed in peak chart.Two acutely transitional zones and two gradually transitional zones were determined based on the change of SED peak.Soil water contents have certain correlation with the distribution patterns of communities.The distribution patterns of communities have a logged response to soil moisture.