Soil pH
Soil pH shows a negative relationship with invertebrate effects on
forest litter decomposition. Microbiota within water films, were clearly
the most sensitive to soil pH (Tao et al. 2019). Tropical soils
are usually acidic due to high leaching intensity driven by high
precipitation (Zhang et al. 2019), with pH levels ranging from
3.8 to 6.2 in our meta-data. In the tropics, litter-feeders with high
acidity tolerance, such as termites, can reach high abundance levels and
so have a competitive advantage over microorganisms, especially bacteria
(Lavelle et al. 1995). Reduced vegetation cover caused by
deforestation leads to soil acidification as lack of organic matter and
root systems lead to loss of soil nutrients (Birhanu et al.2016). Increased land-use intensity with concomitant loss of tree cover,
therefore, threatens soil biodiversity not only through habitat loss but
also by changing soil properties by acidification. This negative effect
may undermine the ecological functions of both microbial and faunal
decomposers, while some highly adapted invertebrates, such as invasive
earthworms and termites, may be responsible for more litter
decomposition in disturbed areas (Liu & Zou 2002; Huang et al.2020).