Testing the applicability of the facilitation model of community succession in terrestrial heterotrophic communities

在陆地生态系统中，分解是一个连续的过程，主要是由昆虫随时间顺序聚集的行为引起的，这种现象被称为异养演替。异养演替已被证明适用于各种分解基质，如动物尸体、粪便、枯木、水果和真菌。与自养演替（即由植物等自养生物主导的时间演替）相比，异养演替发生在相对较小的资源斑块上，这些资源斑块只有在资源本身完全耗尽时才可用。目前，人们对异养演替的动力学机制知之甚少。Connell和Slatyer（1977）所描述的群落演替促进模型被许多人认为是对异养演替背后的主要因果机制的准确解释，它植根于植物和海洋研究，并被广泛地延续到异养系统中。然而，促进模型并没有从分解生态学文献中得到任何经验支持，初步工作表明，它不能解释在异养环境下获得的一些结果。本研究项目的目标是：(i)研究利用各种分解基质的昆虫群落如何应对自然的、大规模的干扰，以启动演替；（ii）确定调节分解基质的景观背景和人为干扰如何影响异养演替；（iii）确定物种谱系和形态方面的特征，可用于预测资源斑块上昆虫物种的发生。(4)验证促进模型在不同异养系统中的适用性。如果群落演替的促进模型最终被拒绝，这项工作可能导致范式转变，对分解生态学的所有领域产生影响。我也希望这个项目能够为法医昆虫学中尸检间隔估计的综合方法的发展奠定基础。

In terrestrial ecosystems, decomposition is a continuous process caused primarily by the action of insects assembling sequentially over time, a phenomenon referred to as heterotrophic succession. Heterotrophic succession has been documented for a variety of decomposing substrates such as animal carcasses, dung, deadwood, fruits, and fungi. In contrast with autotrophic succession (i.e., temporal succession dominated by autotrophic organisms such as plants), heterotrophic succession occurs on relatively small resource patches that are only available until the resource itself becomes completely exhausted. Currently, very little is known about the dynamics governing heterotrophic succession. The facilitation model of community succession as described by Connell and Slatyer (1977), believed by many to be an accurate explanation of the main causal mechanism behind heterotrophic succession, finds root in plant and marine research and has been liberally carried over to heterotrophic systems. However, the facilitation model has not benefited from any empirical support in the decomposition ecology literature and preliminary work suggests that it cannot explain some of the results obtained in a heterotrophic context. The objectives of this research program are (i) to examine how the insect community that exploits a variety of decomposing substrates responds to natural, large-scale disturbances initiating succession, (ii) to determine how landscape context and anthropogenic disturbances regulating the decomposing substrate affect heterotrophic succession, (iii) to identify traits in terms of species lineage and morphology that can be used to predict insect species occurrence at the resource patch, and (iv) to verify the applicability of the facilitation model in different heterotrophic systems. Should the facilitation model of community succession end up being rejected, this work could lead to a paradigm shift, with consequences for all fields of decomposition ecology. I also expect this program to lay the groundwork for the development of integrated approaches of postmortem interval estimation in forensic entomology.