关键词: 物种丰富度, 气候, 中域效应, 面积, 海拔梯度格局, Rapoport法则, 秦岭

Abstract

Spatial patterns of species diversity and range size along environmental gradients and their underlying mechanisms have long been controversial issues in biogeography and ecology. The species-area relationship, water-energy dynamic hypothesis and mid-domain effect were used here to explain the elevational patterns of amphibian and reptile species richness and their different faunal components in China’s Qinling Range using multivariate regression models and the variance partitioning algorithm. Our results showed unimodal patterns for the elevational distributions of amphibians, reptiles and their faunal components, but the peaks of the patterns differed among groups. The underlying mechanisms shaping the patterns revealed intensive interactions, while the independent explanatory strengths of the three proposed hypotheses (exclude reptile oriental realm) were relatively weak. The water-energy dynamic hypothesis was the most parsimonious explanation of the observed patterns. The majority of water-energy dynamic explanation belonged to interaction of three hypotheses. The interaction between mid-domain effect and water-energy dynamics was larger for amphibians and that between species-area relationship and water-energy dynamic hypothesis was larger for reptiles. The Steven’s and cross-species methods were used to examine whether species-specific elevational range sizes of amphibians, reptiles and their different faunal components are applicable to Rapoport’s rule. The results showed that reptile range sizes supported Rapoport’s rule at the various elevational gradients, while amphibian range sizes were difficult to support Rapoport’s rule.

Key words: species richness, climate, mid-domain effect, area, elevational gradient pattern, Rapoport’s rule, Qinling Range