Reducing tillage intensity benefits the soil micro- and mesofauna in a global meta-analysis.

Abstract

Abstract Soil fauna drives crucial processes of energy and nutrient cycling in agricultural systems, and influences the quality of crops and pest incidence. Soil tillage is the most influential agricultural manipulation of soil structure, and has a profound influence on soil biology and its provision of ecosystem services. Understanding the effects of different tillage intensities is of interest not only to the scientific community, but also to farmers, practitioners, policy makers and agricultural consultants. We present the results of a global meta-analysis of available literature data on the effects of different tillage intensities on taxonomic and functional groups of soil fauna. We collected paired observations (conventional vs. reduced forms of tillage/no tillage) from 133 studies across 33 countries published in the last 31 years. Our results show that reduced tillage intensity or no tillage increases the total density of springtails (+35%), mites (+23%) and enchytraeids (+37%) compared to more intense tillage methods. The meta-analyses for different nematode feeding groups, life-forms of springtails, and taxonomic mite groups showed positive effects on omnivorous nematodes (+53%), epedaphic (+81%) and hemiedaphic (+84%) springtails, oribatid (+43%) and mesostigmatid (+57%) mites. Additional meta-analyses showed that the effects of reduced forms of tillage on soil fauna vary with depth, climate and soil texture, as well as with tillage method, tillage frequency, concurrent fertilization, and herbicide application. Our findings suggest that reducing tillage intensity will allow the recovery of faunal communities in areas subjected to long-term intensive cultivation practices. Our results will be useful to support decision making on management of soil faunal communities and will facilitate modelling efforts of soil biology in global agroecosystems.