摘要
在使用 5m× 50 0 0 m样带进行调查获得的植被盖度数据的基础上 ,通过半方差分析和分形分析揭示了毛乌素沙化草地沙生半灌木群落植被盖度的空间变异特点。半方差分析揭示出植被盖度的多尺度变异和等级斑块结构 ,在取样范围内至少存在着 3个等级。分形分析得出毛乌素沙地沙生半木群落植被盖度的分维 D=1 .90 ,接近于 2 ,指示着大部分空间变异发生在较小的尺度上 ;分段分形分析得出不同尺度范围内的分维 ,反映了空间异质性的多尺度变异性。
Based on the data from field investigation along a 5 km transect,spatial variant features of the vegetation coverage of the psammophytic half shrub community in Mu Us Sandland was described through semivariance analysis and fractal analysis.Nested structure of the vegetation coverage and its multiple scale of variability were revealed by semivariance analysis.There were at least three scales of variability over the sampling range.Fractal dimension of the vegetation coverage was estimated by fractal analysis.It was 1.90,suggesting the dominance of variations of smaller scales.Fractal dimensions at different scales were obtained through piecewise fractal analysis,which reflecs the multi scale variation in spatial heterogeneity of the community.This result reveals habitat fragmentation caused by the desertification in this region.
出处
《生态学报》
CAS
CSCD
北大核心
2000年第4期568-572,共5页
Acta Ecologica Sinica
基金
国家杰出青年科学基金!(No.39825106)
中国科学院资源与生态环境研究重大项目!(KZ951-B1-1 08)资助
关键词
空间异质性
半灌木群落
植被盖度
毛乌素沙地
spatial heterogeneity
the psammophytic half shrub community
vegetation coverage
semivariance analysis
fractal analysis
Mu Us Sandland
