The patterns and causes of elevational diversity gradients

作者：Nathan J. Sanders, Carsten Rahbek · 发表于：Ecography · 年份：2011 · DOI：10.1111/j.1600-0587.2011.07338.x · 被引用次数：521 · 研究领域：Ecology and Vegetation Dynamics Studies、Species Distribution and Climate Change、Animal Ecology and Behavior Studies

A major focus of research in spatial ecology over the past 25 years has been to understand why the number of species varies geographically. ! e most striking, and perhaps best documented, pattern in spatial ecology is the latitudinal gradient in species diversity in which the number of species, for most taxa, declines with increasing latitude. Understanding the underlying cause(s) of the latitudinal gradient has proven challenging, perhaps because there are really only two latitudinal gradients (in the northern and southern hemispheres), and because it is often diffi cult to perform experiments at latitudinal scales. Elevational gradients in species diversity are nearly as ubiquitous as latitudinal gradients, and they off er many characteristics that make them perhaps more suitable for uncovering the underlying cause(s) of spatial variation in diversity. First, there are many replicates of elevational diversity gradients – essentially each mountain or mountain range is a replicate, so it is possible to test for the generality of the underlying cause(s). Second, it is possible to carry out manipulative experiments along elevational gradients. ! ird, fi eld data can be collected more readily along elevational gradients than along latitudinal gradients, simply because the spatial extent of elevational gradients is small relative to latitudinal gradients. Finally, many of the potential underlying causes that covary along latitudinal gradients (history, climate, time since glaciat...