Combined Impact of No-Till and Cover Crops with or without Short-Term Water Stress as Revealed by Physicochemical and Microbiological Indicators

摘要

Farming systems in which no-till (NT) and cover crops (CC) are preferred as alternatives to conventional practices have the promise of being more resilient and climate smart. Our field study aimed to assess the long-term impact of NT plus CC, with vs. without short-term water stress, on soil microbial biodiversity, enzymatic activities, and the distribution of C and N pools within soil aggregates. We found that the diversity of bacteria and fungi in the soil was positively affected by NT + CC, especially under water stress conditions. Under NT + CC, the presence of important plant growth-promoting rhizobacteria was revealed. Soil enzymatic activity confirmed the depleting impact of conventional tillage. Soil C and N were increased under NT + CC due to their inclusion into large soil aggregates that are beneficial for long-term C and N stabilization in soils. Water stress was found to have detrimental effects on aggregates formation and limited C and N inclusion within aggregates. The microbiological and physicochemical parameters correlation supported the hypothesis that long-term NT + CC is a valuable strategy for sustainable agroecosystems, due to its contribution to soil C and N stabilization while enhancing the biodiversity and enzymes.