Leaf litter, as a multifunctional legacy of plants, plays an essential role in driving biogeochemical cycles, while providing important habitat and food resources for soil organisms. Litter traits and soil fauna play a crucial role in determining litter decomposition. However, the extent to which soil fauna contributed to litter decomposability is still unknown. Neither do the leaf size and defensive traits when compared to economic traits.
Researchers from the Wuhan Botanical Garden of the Chinese Academy of Sciences (CAS), in collaboration with researchers from Northwest Institute of Plateau Biology of CAS, conducted a meta-analysis to synthesize existing research on the effects of leaf traits and soil fauna on litter decomposability on a global scale.
According to the researchers, soil fauna significantly accelerated the decomposition rate across different climate zones (e.g., tropical, subtropical, temperate, and alpine climate zones), ecosystems (e.g., forest, grassland, wetland, and farmland), and litter types (e.g., evergreen woody plants, deciduous woody plants, annual herbs, and perennial herbs). The combined influence of climate factors (mean annual temperature and precipitation) and litter quality served as a robust predictor of the contribution of soil fauna to litter decomposability across different biomes.
Leaf size traits (leaf length, width and area) positively modulated the effect of soil fauna on litter decomposition, whereas the defensive traits (cellulose, hemicellulose, total phenols, and condensed tannins concentration) were negatively correlated. Among the economic traits, specific leaf area and phosphorus concentration were positively correlated with faunal response rate in modulating litter decomposition, while carbon and nitrogen were not significantly correlated.
This study highlights the critical role of soil fauna and litter quality on leaf litter decomposition, and suggests that leaf size and defensive traits play important roles in modulating the effects of soil fauna on litter decomposition.
This work entitled "Effects of leaf size and defensive traits on the contribution of soil fauna to litter decomposition" was published in Forests, and it was supported by the Knowledge Innovation Program of Wuhan-Basic Research and China Scholarship Council.
