Soil biodiversity, food security and nutrition

The soil functions are the base of agricultural activities and, hence, assure food productivity. However, increasing evidence indicates that agricultural intensification affects soil biodiversity and that such changes may have a very significant impact on the future of food security. Changes in land use or agricultural management affect soil biodiversity through: aboveground biomass removal/returns, use of agrochemical inputs and mechanical soil disturbance. Increasing evidence suggests that organic or agro-ecological farming leads to positive effects and helps in mitigating the decline in soil biodiversity, while reducing the dependency on external inputs.

Food demand is increasing. In contrast, land use conversion and inadequate management practices threaten the availability and stability of food supplies. In this context, the biotic component of the soil plays essential roles in soil dynamics such as carbon/nutrient cycling, nutrient uptake by plants and soil organic matter formation. Furthermore, soil organisms, namely earthworms and termites contribute to soil formation and regeneration through bioturbation and soil structuration. Soil organisms also contribute to the control of plant, animal, and human pests and diseases, and have a vital responsibility in regulating the adaptive capacity of the soil to global changes. Thus, an integrated management of soil biodiversity offers the potential to increase agricultural productivity by making more efficient use of resources, reducing yield variability, production costs and economic risks for the farmers, ultimately contributing decisively to food security. A holistic approach to agricultural land management consists of managing soil ecosystems and their diversity in a way that favors multifunctionality, resilience and adaptive capacity of the soil against environmental changes. This enhances agricultural productivity, an efficient application of resources and results in stable food production. This holistic approach considers the complexity, complementarity and self-regulation of soil biota and plant-soil biota interactions. In practical terms, it implies working closely with farmers to increase understanding and knowledge sharing about soil biodiversity and its role in food security. The implementation of a holistic approach to soil biodiversity management requires the diversification of the entire agroecosystem, through practices such as crop livestock integration, agroforestry, intercropping and crop rotation.

To think about: Proper human nutrition depends on the availability and balance of different nutrients in the soil and the ability of plants to extract those nutrients. Thus, nutrient limitations in the soil can lead to nutritional deficiencies in the food produced.