Changes of soil structure and earthworm community under different agricultural management

The living soil is represented by soil biota that interacts with aboveground biota and with the abiotic constructs of soil, represented as soil structure, organic matter, and nutrients. Maintenance of soil organic matter through integrated soil fertility management is necessary for soil quality and agricultural productivity. Earthworms are key actors in soil structure formation through the formation of casts and the incorporation of soil organic matter in the soil. Little is known about the interactive effects of various tillage and crop residue management practices on earthworm populations and physical properties of soil.
<br />To investigate the impacts of two tillage management systems and two cropping systems on earthworms populations and soil stucture dynamics, we carried out a three years study of the earthworm communities in experimental site having for experimental treatments : two tillage management systems and two cropping systems. In consequence, the aims of this experimentation were to determine the effects of the tillage systems on the abundance, biomass and diversity of earthworms and examine temporal variation of soil structure and dynamics of nutrient elements.
<br />The first results reveal that tillage management had a significant affect on earthworm abundance and biomass. However, crop residue management did not affect abundance, biomass and diversity of earthworms. The analyze of nutrient element dynamics showed that some nutrient elements (phosphore,…) decrease with tillage practice. This study has shown that soil structure was variable within the fields and between them, although the successive cultivation operations and the equipement used for wheat cropping were identical in the study site.