Fenner School of Environment and Society, The Australian National University, Canberra, Australian Capital Territory, Australia.
PLoS One. 2013;8(1):e53961. doi: 10.1371/journal.pone.0053961. Epub 2013 Jan 11.
Carrion is an ephemeral and spatially patchy resource that supports a diverse subset of species linked to nutrient cycling and the decomposition process. A number of studies have separately documented changes in the diversity of plants, arthropods and vertebrates at individual carcasses, but there are few studies that have examined how functional traits of different groups of organisms underpin their responses to carrion patches. We used a carrion addition experiment to compare changes in composition and functional traits of insect and plant assemblages at carcasses compared with control sites. We found that significant changes in insect assemblage evenness and heterogeneity was associated with species' dispersal traits, and that plant assemblage responses to subsequent soil nitrogen changes was most apparent among graminoids and exotic species. Beetles at carcasses were twice as large as their counterparts at control sites during the first week of carrion decomposition, and also had higher wing loadings. Plants with high specific leaf area responded faster to the carcass addition, and twice as many species recolonised the centre of carcasses in exotic-dominated grassland compared with carcasses in native-dominated grassland. These results provide an example of how traits of opportunist species enable them to exploit patchy and dynamic resources. This increases our understanding of how carcasses can drive biodiversity dynamics, and has implications for the way carrion might be managed in ecosystems, such as appropriate consideration of spatial and temporal continuity in carrion resources to promote heterogeneity in nutrient cycling and species diversity within landscapes.
腐肉是一种短暂且空间上呈斑块状的资源,它支持着与营养循环和分解过程相关的多种物种。许多研究分别记录了单个腐肉上植物、节肢动物和脊椎动物多样性的变化,但很少有研究探讨不同生物类群的功能特征如何支撑它们对腐肉斑块的响应。我们使用腐肉添加实验来比较腐肉和对照点上昆虫和植物组合的组成和功能特征的变化。我们发现,昆虫组合均匀度和异质性的显著变化与物种的扩散特征有关,而植物组合对随后土壤氮变化的反应在禾本科植物和外来物种中最为明显。在腐肉分解的第一周,腐肉上的甲虫比对照点上的甲虫大两倍,翅膀的负载也更高。具有高比叶面积的植物对腐肉添加的反应更快,与在以本地植物为主的草原相比,在以外来植物为主的草原中,有两倍多的物种重新出现在腐肉的中心。这些结果提供了一个例子,说明机会主义物种的特征如何使它们能够利用斑块状和动态的资源。这增加了我们对腐肉如何驱动生物多样性动态的理解,并对腐肉在生态系统中的管理方式产生了影响,例如适当考虑腐肉资源的时空连续性,以促进景观内养分循环和物种多样性的异质性。