基于均匀度理论的胡杨种群空间分布格局研究

Study on the Spatial Distribution Pattern of Populus euphratica Population Based on Uniformity theory

本文采用均匀度理论与ARCGIS相结合来研究四个退化不一的胡杨结构及分布,结果表明:胡杨种群数量变化明显(从A断面的197株下降至D断面的19株),地下水埋深度对胡杨数量影响显著;胡杨种群整体分布呈现集聚格局,幼苗和小树缺少,随着种群的不断退化,种群中幼小树苗所占比重也在不断降低;在该区域中胡杨的种群呈现聚集分布的格局,均匀度指数从A断面的0.1795(聚集度强度S为5.5710)降至D断面的0.1036(聚集度强度S为9.6525),而且在幼小树苗发育阶段胡杨的种群则呈现出随机分布的格局,但是在中老龄阶段胡杨的种群则呈现出聚集分布的格局;种群的聚集度也随着地下水位加深而增加。

Uniformity theory combined with ARCGIS to study the different degree of 4 typical sections of population structure and spatial distribution pattern of Populus euphratica in the lower reaches of Tarim River.The results showed:The number of P.euphratica decreased remarkably(from 197 strains of the A section to 19 of the D section),groundwater depth played a important role;The overall distribution of P.euphratica was clustering pattern,lack of seedlings and saplings.With the increase of degradation degree,the proportion of seedlings and saplings decreased continuously;The whole population distribution pattern was aggregated distribution,evenness index from 0.1795 of the A section(the aggregation intensity S was 5.5710)to 0.1036 of the D section(the aggregation intensity S was 9.6525),and the population distribution pattern in saplings growth stages gradually transformed into random distribution,while populations in middle and old age stages were aggregated distribution;the aggregation intensity increased continuously with the increase of groundwater depth.