Climatic variables
We demonstrated that soil invertebrate contributions to forest litter decomposition are positively related to temperature and precipitation. Climate can moderate faunal decomposition through its impacts upon invertebrate activities (Thakur et al. 2018). Low temperature or water-limited conditions in subtropical, temperate, and boreal forests limit soil invertebrate activities and their decomposing effects (David & Handa 2010; Castanho et al. 2012). The behaviour of some invertebrate decomposers are directly sensitive to temperature. Foraging termites, for example, show increasing discovery rates with increasing temperature (Zanne et al. 2022). For precipitation, many soil organisms are sensitive to low soil moisture. Protozoa, nematodes and mites, for instance, live within water droplets or films and are directly affected by water potential (Hoeffner et al. 2019). Some soft-bodied meso- or macro-invertebrates (e.g. earthworms) are also susceptible to moisture stress (Swift et al. 1979). In contrast, invertebrates that mainly occupy the litter layer or air-filled soil spaces (e.g. termites, isopods, millipedes and beetles), have lower water sensitivity and are more resistant to desiccation (Swift et al. 1979; Berg & McClaugherty 2020). Foraging discovery rates and activities of termites may even be enhanced with increasing drought, enhancing their ecological importance in extreme droughts (Ashton et al. 2019). Any loss of decomposer organisms driven by climate change, therefore, may lead to a decrease in future litter decomposition (Wall et al. 2010), but the relative magnitude of termite impacts on biogeochemistry may increase at the Earth’s surface with increasing tropicalization (Zanne et al.2022).