Local and regional diversity of frog communities along an extensive rainforest elevation gradient in Papua New Guinea

Rainforests on high tropical mountains are globally important species diversity hotspots. We studied amphibians along an extensive rainforest elevation gradient on Mt. Wilhelm (4,509 m) in Papua New Guinea. We established eight sites at 500 m elevation increments between 200 and 3,700 m a.s.l. and related their community composition to the known species pool of New Guinea island. We recorded 3,390 frogs from 55 species, which is three times more species than at any local community along the elevation gradient. Species diversity peaked at 1,700 m a.s.l. for Mt. Wilhelm communities, and at 500–1,100 m a.s.l. in the broader New Guinea fauna, probably reflecting increasing speciation and decreasing dispersal rates with increasing elevation. The beta diversity between frog communities was high and increased with increasing elevation. The change in frog community composition across 500 m elevation corresponded to the change over 200 km distance within lowland forests. A majority of frog speci...

热带高山雨林是全球范围内具有重要生态意义的物种多样性热点区域。本研究针对巴布亚新几内亚境内海拔4509米的威廉山（Mt. Wilhelm）沿线大范围雨林的海拔梯度开展两栖动物调查：我们在海拔200至3700米的区间内，以500米为间隔设置了8个采样点，并将各采样点的蛙类群落组成与新几内亚岛已知的物种库（species pool）进行关联分析。本次研究共记录到55种蛙类共计3390只个体，该物种丰富度是该海拔梯度上任意单一本地群落的三倍。威廉山蛙类群落的物种多样性在海拔1700米处达到峰值，而整个新几内亚岛蛙类区系的物种多样性峰值则出现在500至1100米海拔区间，这一差异或反映了随海拔升高，物种形成速率上升而扩散速率下降的生态学规律。蛙类群落的β多样性（beta diversity）较高，且随海拔升高而显著增加。海拔每升高500米所带来的蛙类群落组成变化，相当于低地森林中200公里空间跨度所引发的群落组成变化。多数蛙类的物种形成……