Mechanisms of earthworms to alleviate continuous cropping obstacles through regulating soil microecology

Abstract

Obstacles to continuous cropping seriously affect crop yield and also lead to a series of microecological imbalance problems, such as the decline of soil biodiversity, the decrease of beneficial microbes, and the increase of pathogens. The imbalanced soil microecology affects plants and can lead to more serious disease and even greater reduction of crop yield. As soil ecosystem engineers, earthworms have important regulating effects on soil microecology. Earthworms can improve the soil environment and strengthen the function of soil biological communities through their activities (e.g. feeding, burrowing and creeping), thus providing a potential way to alleviate microecological obstacles to continuous cropping. This paper reviews the progress made in research on soil microecology, soil function maintenance, and earthworm regulation of soil biological function. Three mechanisms that earthworms employ to alleviate obstacles to continuous cropping through soil microecology regulation were identified: direct regulation of soil microbial communities, regulation of microbial colonies by changing allelochemical composition, and regulation of soil fauna communities. Through earthworm regulation of microbial communities, an imbalanced soil microenvironment in the rhizosphere is corrected, thereby alleviating obstacles to continuous cropping.