Soil fauna communities are known to change during succession as the soil ages and vegetation develops. Moreover, plant functional identity (PFI) influences belowground assemblages within successional stages. Given changes in soil carbon (C) and nutrient content, this influence of PFI is likely to differ across successional stages; however, the relative contribution of PFI across successional stages remains unknown. We sampled nematode communities associated with nitrogen (N) fixing and non-fixing tree species across a well-described chronosequence (Cooloola, QLD, Australia) to assess the relative importance of PFI and successional stage on nematode community composition. Nematode densities were influenced by successional stage, peaking at the late progressive stage, associated with similar patterns in C and N contents. Successional stage and PFI accounted for more than half of the observed variation in nematode assemblage composition. K-strategists increased in abundance in the later successional stages while the two PFIs supported distinct communities by favouring certain genera. This supports our hypothesis that nematode assemblages change during succession, but that PFI plays a key role in structuring nematode communities within successional stages. Contrary to our expectations, there was no interaction between the two factors, indicating that PFI has largely consistent influences on soil nematode assemblage composition across successional stages. Still, a significant interactive effect of PFI and soil age on the basal and enrichment indexes indicate that nematode contributions to ecosystem functions associated with PFIs differ somewhat as succession proceed.

众所周知，随着土壤年龄和植被的发展，土壤动物群落会在演替过程中发生变化。此外，植物功能特性 (PFI) 会影响演替阶段的地下组合。鉴于土壤碳 (C) 和养分含量的变化，PFI 的这种影响可能因演替阶段而异；然而，PFI 跨演替阶段的相对贡献仍然未知。我们对与固氮和非固氮树种相关的线虫群落进行了采样，这些线虫群落跨越一个描述良好的时间序列（库鲁拉，昆士兰州，澳大利亚），以评估 PFI 和演替阶段对线虫群落组成的相对重要性。线虫密度受演替阶段的影响，在晚期渐进阶段达到峰值，与 C 和 N 含量的相似模式相关。演替阶段和 PFI 占观察到的线虫组合组成变化的一半以上。K-策略在演替后期大量增加，而两个 PFI 通过偏爱某些属来支持不同的群落。这支持我们的假设，即线虫组合在演替过程中发生变化，但 PFI 在演替阶段内构建线虫群落中起着关键作用。与我们的预期相反，这两个因素之间没有相互作用，这表明 PFI 对整个演替阶段的土壤线虫组合组成具有基本一致的影响。尽管如此，PFI 和土壤年龄对基础和富集指数的显着交互作用表明，随着演替的进行，线虫对与 PFI 相关的生态系统功能的贡献有所不同。