Enhanced dissipation of xenobiotic agrochemicals harnessing soil microbiome in the tillage-reduced rice-dominated agroecosystem

Abstract

The ubiquitous contamination generating from the frequent input of agrochemicals is a major hurdle affecting the ecological sustainability of agroecosystems. Here, we investigated the dissipation of multiple pesticides in the subtropical rice-dominated landscapes under tillage intensity management, and unveiled the vital role of soil microbiome in promoting xenobiotic degradation. Three commonly used pesticides (including herbicide butachlor, insecticide clothianidin and fungicide tricyclazole) showed rapid dissipation dynamics in the field where the reduction of tillage intensity with straw incorporation was conducted. In response to pesticide exposure, soil microbial communities adapted quickly with slight changes in community composition and diversity. Meanwhile, the microbial xenobiotic degradation-related functions were stimulated, which possibly related to the increased organic carbon and nitrogen in soil. Importantly, these shifts and effects on microbial communities and functions gradually declined after a length of rice growing seasons, suggesting the flexibility of soil microbiome in tackling with long-term xenobiotic disturbance to maintain a diverse and vibrant soil biota. Overall, our study that displayed the enhanced agrochemical dissipation which benefited markedly from the interaction of tillage management and soil microbial functioning, provides important basis and insights for facilitating green, balanced and sustainable agriculture.

Keywords: Agrochemical; Dissipation; Microbial communities; Soil properties; Sustainability.