This cross-cutting initiative addresses the multiple links between biodiversity and soil.

Soil biodiversity contribute to ecosystems services

Many thousands species of animals and micro-organisms live in soils, ranging in size from the almost invisible microbiota (e.g. bacteria, fungi and protozoa) to the more conspicuous macrofauna and megafauna (e.g. earthworms, termites, millipedes, moles and rats). The activities of this wide range of soil biota contribute to many critical ecosystem services. These services include:

• Soil formation
• Organic matter decomposition, and thereby nutrient availability and carbon (C) sequestration, and conversely greenhouse gas emissions
• Nitrogen (N2) fixation and plant nutrient uptake
• Suppression or induction of plant diseases and pests
• Bioremediation of degraded and contaminated soils, through detoxification of contaminants and restoration of soil physical, chemical and biological properties and processes

The effects of soil organisms also influence water infiltration and runoff and moisture retention through effects on soil structure and composition and indirectly on plant growth and soil cover. These services are critical to the functioning of natural ecosystems and constitute an important resource for sustainable agricultural production.