Limited effects of woody debris on soil function a decade after placement

Abstract Introduction Coarse woody debris is widely recognized as supporting macrofaunal and microbial diversity, yet its role in influencing soil function is often presumed, rather than known, particularly in drylands where there are few studies. Objectives We sought to explore whether the addition of woody debris enhanced soil function. Methods We examined the effects of the addition of coarse woody debris (logs) on soil labile carbon, pH, electrical conductivity, and 20 micronutrients, five plant compositional measures, and nine functional measures of surface soils. Results We found limited evidence that coarse woody debris enhances any of our measures of soil function or plant structure and composition. The volume of coarse woody debris was negatively associated with overall soil function, and we found no differences between the two sites where woody debris was placed 3 and 12 years previously. Litter emerged as a significant driver of soil functioning. Further, locally derived litter and a surface free of detached sandy sediments were significantly correlated with the presence of coarse woody debris. Conclusions Our results highlight the critical role of litter in the restoration process and show that the response to coarse woody addition is likely to be protracted.