Soil Microarthropods: Biodiversity and Role in Grassland and Agroforestry Ecosystems

A variety of organisms inhabit soil; many of them are still unknown. Each organism has a specific role in the complex web of life in the soil. They are mainly responsible for soil organic matter turnover and nutrient cycling through a diversity of processes. The microarthropods are mostly soil or litter dwellers and transform plant litter physically and chemically into substances amenable to further degradation by microflora and vice versa. Grassland and agroforestry systems on account of their perennial nature harbour a wider diversity of soil biota in comparison with agricultural systems. The interactive effects of soil biota and grassland/agroforestry systems are not understood to the desired levels. Also, there is little research on the role of soil biota in various other land use systems. Now, soil degradation has emerged as a global problem that leads to desertification, erosion and depletion of fertile lands. This has led to an in-depth look into reliable scientific information on soils, especially the biodiversity and many services they provide. It has created a demand for agricultural practices that are less dependent on external inputs, tighten nutrient cycles and are productive without degrading soil. The available work on soil organisms, especially the grassland and agroforestry systems from tropical areas, is reviewed, and some future thrust areas are suggested.