Coetzee Bernard W T, Chown Steven L
Centre for Invasion Biology Department of Botany and Zoology Stellenbosch University Private Bag X1 Matieland 7602 South Africa.
School of Biological Sciences Monash University Melbourne Victoria 3800 Australia.
Ecol Evol. 2016 Oct 5;6(21):7610-7622. doi: 10.1002/ece3.2389. eCollection 2016 Nov.
Land-use change may alter both species diversity and species functional diversity patterns. To test the idea that species diversity and functional diversity changes respond in differing ways to land-use changes, we characterize the form of the change in bird assemblages and species functional traits along an intensifying gradient of land use in the savanna biome in a historically homogeneous vegetation type in Phalaborwa, South Africa. A section of this vegetation type has been untransformed, and the remainder is now mainly characterized by urban and subsistence agricultural areas. Using morphometric, foraging and breeding functional traits of birds, we estimate functional diversity changes. Bird species richness and abundance are generally higher in urban and subsistence agricultural land uses, as well as in the habitat matrix connecting these regions, than in the untransformed area, a pattern mainly driven through species replacement. Functionally unique species, particularly ground nesters of large body size, were, however, less abundant in more utilized land uses. For a previously homogenous vegetation type, declines in the seasonality of energy availability under land-use change have led to an increase in local avian diversity, promoting the turnover of species, but reduced the abundance of functionally unique species. Although there is no simple relationship between land-use and diversity change, land-use change may suit some species, but such change may also involve functional homogenization.
土地利用变化可能会改变物种多样性和物种功能多样性模式。为了验证物种多样性和功能多样性变化对土地利用变化的响应方式不同这一观点，我们在南非法拉伯瓦历史上植被类型单一的热带稀树草原生物群落中，沿着土地利用强度梯度，对鸟类群落和物种功能性状的变化形式进行了表征。这片植被类型中有一部分未被改变，其余部分现在主要以城市和自给农业区为特征。利用鸟类的形态测量、觅食和繁殖功能性状，我们估算了功能多样性的变化。与未被改变的区域相比，城市和自给农业土地利用以及连接这些区域的栖息地矩阵中的鸟类物种丰富度和丰度通常更高，这种模式主要是由物种替代驱动的。然而，在利用程度更高的土地利用类型中，功能独特的物种，特别是大型地面筑巢鸟类，数量较少。对于以前单一的植被类型，土地利用变化导致能量可利用性季节性下降，从而增加了当地鸟类的多样性，促进了物种更替，但减少了功能独特物种的数量。尽管土地利用与多样性变化之间没有简单的关系，但土地利用变化可能适合某些物种，但这种变化也可能导致功能同质化。
