环境因子对滇西北地区植物多样性分布格局的影响

利用一元回归分析和偏回归分析,探讨了滇西北地区温、热带植物的分布格局及其控制因素.结果表明,温带植物多样性的高值主要出现在研究区域北部,而热带植物多样性则未呈现明显的纬度趋势.热带植物比重高值主要出现在研究区域南部,而温带植物比重高值主要出现在北部.生境异质性对温带植物多样性的解释率明显高于对热带植物多样性的解释率.这意味着,生境异质性对多样性格局的影响力可能在一定程度上取决于植物的生物地理分布区性质.气候因子对温、热带植物比重的解释率明显高于对温、热植物多样性的解释率.相比气候因子与温、热带植物多样性的关系,气候因子与温、热带植物比重之间关系可能更能反映滇西北地区温、热带植物的生态位保守性.

Effects of Environmental Factors on Spatial Patterns of Plant Diversity in Northwest Yunnan

Univariate and partial regressions were used to investigate the influences of predictors. Higher temperate species diversity was mostly observed in the northern parts of the study area,whereas,no any obvious latitudinal trends were observed on tropical species diversity. Higher proportions of tropical species were observed in the southern parts,whereas those of temperate species were observed in the northern parts. Habitat heterogeneity explained higher percentage of the spatial variation of temperate species diversity than for that of tropical species diversity. It may imply that the influence of habitat heterogeneity on plant diversity may be modified by the taxa's biogeographic affinities. Higher percentages of variation in the proportions of tropical and temperate species than those of tropical and temperate species diversities were explained by climate predictors. It suggested that niche conservatism of tropical and temperate plants in the study area was more accurately reflected by the associations between species diversity with tropical and temperate affinities and climatic conditions than those between the proportions of tropical and temperate plants and climatic conditions.