土壤动物对森林凋落物分解的影响:机制和模拟

Effects of soil fauna on the decomposition of forest litter: Mechanism and modeling

土壤动物是森林生态系统的重要组成部分。本文综述了土壤动物在不同森林生态系统中对凋落物分解过程的贡献大小及影响因素、土壤动物影响凋落物分解的作用机制以及凋落物分解模型的研究进展,以期为更好地理解森林生态系统中土壤动物在地上、地下生态过程中的作用。我们试图建立一个概念模型来模拟土壤动物在凋落物分解过程中的贡献。土壤动物可以通过直接作用于凋落物(包括移动、破碎、取食等),或间接作用于土壤(穿梭、掘穴等影响凋落物分解微环境)和微生物(影响定殖于凋落物中的微生物群落种类、数量和活性)影响凋落物的分解过程。温度和水分条件是影响土壤动物活动的重要因素,普遍认为热带森林中的土壤动物作用要大于亚热带森林、温带森林和高山/亚高山森林。未来该领域的研究应注重如何在凋落物分解模型中体现土壤动物的作用机制以及利用野外实验数据量化土壤动物对凋落物分解过程的贡献等。

Soil fauna is an important component of forest ecosystems.We reviewed the contribution of soil fauna on litter decomposition in different forest ecosystems and the influencing factors,the underlying mechanisms of soil fauna affecting litter decomposition,and research advances on litter decomposition models,aiming to better understand the effects of soil fauna on aboveground and belowground ecological processes in forest ecosystems.We proposed a novel framework for modeling litter decomposition by considering the contribution of soil fauna.Soil fauna can affect litter decomposition by acting directly on litter(including moving,breaking and feeding,etc.)or indirectly on the soil(affecting litter decomposition microenvironment through shuttling and burrowing)and microorganisms(influencing the composition,quantity and activities of microbial communities which colonized in litter).Temperature and moisture are important factors affecting activities of soil fauna.The effects of soil fauna on litter decomposition in tropical forests are stronger than in subtropical forests,temperate forests and alpine/subalpine forests.Future modeling studies should focus on how to mimic the effects of soil fauna on litter decomposition and validate the modeling results using field experiment data.