Decomposition has been studied for decades due to its significance in understanding nutrient cycling and carbon sequestration processes. The current study identified the three interacting factors that control decomposion: the physicochemical environment, litter quality, and decomposer organisms. Exsiting biogeochemical models that that are derived by local cliamte and little quality parameters can explain about 70% of the variation in litter decomposition. However, the role of soil organisms has been largely ignored in these models that assume the functions of soil organisms are mainly controlled by temperature, moisture and litter quality. Recent studies suggest that leaf litters tend to decompose more rapidly in the habitat from which it was derived (i.e. home) than in other habitats (i.e. new home away from its origion), this phenomena has been termed as the home-field advantage (HFA ) in litter decomposition.
In contrast to plant growth, leaf litter-soil feedbacks are expected to consistently cause positive feedback at a home habitat resulting in faster litter decay. This is because 1) leaf litter from different plant species often varies considerably in structure and chemical composition; and 2) leaf litter inputs are a major source of nutrients and energy for soil biota that access decomposed litter. Thus, competition among soil biota for accessing nutrients may create a selective pressure for organisms that are efficient at breaking down litter derived locally resulting in HFA.. Unique soil biota developed in the litter derived from the orgional ecosystem has been regarded as the reason for this phenomenon. quantifying HFA is more complex than a simply comparison between the decomposition rates for a litter type at its home site and an away site, because differences in environmental contitions between the sites could also influence decomposition. The method originally developed for evaluating home-site effects in sports allows the HFA to be calculated for each of the litters separately in fully reciprocal transplants experiment of three or more litter species.
Existing literature suggests there is a large amount of variation in HFA among reciprocal transplants between different tree species. Differences in litter traits could explain some of these variations, but it is apparent that other factors influence the relationship given the initially large HFA observed in field and laboratory experiments, as well as periods of home-field disadvantage. Thus we need a better understanding of the drivers of HFA and how soil biota are involved in order to address this potential problem in how we model decomposition. Based on the review about the rules of soil organisms on litter decompositon, three mechanisms are considered to reveal the soil biological drive of HFA: soil microorganism adjustability has a weakening effect on the HFA, soil animals' late entry can lead to different HFA intensity, including a disadvantage of home decomposition, environmental climatic conditions have indirect effects on HFA, especially under soil water stress.Integrating these using an ecosystem approach helps to elucidate the effects of soil organism on the HFA of litter decomposition, and interpret the causes of different intensity, especially negative effect of HFA. In order to clearly understand the effects of soil organisms on HFA, long term reciprocal litter transplant experiments, including in-situ and laboratory, should be established across a large geographic and climatic gradient. Based on the effects of soil organisms on HFA, mathematical models of litter decomposition should incorporate with biological factors. This is especially important for global ecosystems that are used for understaing climate change effects on carbon and nutrient cycles.