地形汇流值与土壤水分和树种分布格局的关系

Relationships Between Flowaccumulation and Soil Moisture and Tree Distribution Pattern

以张家沟一典型的小流域集水区为研究对象,在GIS技术支持下,利用地形图生成地形汇流值及地形指数分布图概化该地区的地形水文特征,结合实际的野外调查与分析,探讨了汇流值与土壤水分及树种分布格局的关系。结果表明:栅格为10m×10m和12m×12m时,汇流值与土壤含水率呈显著正相关,相关系数可达到0.8190和0.8705;栅格为18m×18m时,汇流值与土壤含水率的相关系数仅为0.3002,二者相关性不显著。所研究的树种多分布在汇流值较小的区域,但就其树种组成来看,色木(Acermono)、水曲柳(Fraxinus mandshurica)和黄波椤(Phellodendron amurense)的空间分布与汇流值的相关性较强;蒙古栎(Quercus mongolica)、春榆(Ulmuspumi-la)、紫椴(Tilia amurensis)、白桦(Betula platyphylla)和胡桃楸(Juglans mandshurica)的空间分布与汇流值的相关性较弱。

The goal of this paper is to discuss the relationships between flowaccumulation and soil moisture and tree distribution patterns in Zhangjiagou,a typical small catchment,with the help of GIS technology.Through field survey and analysis,the flowaccumulation and topographic indexes extracted from a digitized topographic map were used to depict the topographic hydrologic characters.Result showed that,when the size of grid was 10 m×10 m or 12 m×12 m,a significant positive correlation was found between the flowaccumulation and soil moisture with the correlation coefficients of 0.819 0 or 0.870 5;when the size of grid was 18 m×18 m,no significant correlation was observed （0.300 2）.Most of the studied tree species distribute in the area where exhibits low value of flowaccumulation,but the spatial distribution patterns of Acer mono,Fraxinus mandshurica and Phellodendron amurense showed stronger correlations with the flowaccumulation compared with those of Quercus mongolica,Ulmus pumila,Tilia amurensis,Betula platyphylla and Juglans mandshurica.