Concepts and Practices for Managing Soil Health

Most agricultural soils in the Global South have inherently poor soil fertility status due to the old nature of soils. Coupled with this, high erosion and nutrient depletion lead to biological, chemical, and physical soil degradation. Furthermore, the low organic matter content in many soils in the Global South results in soils having poor structure, reduced soil moisture, low microbial activity, low cation exchange capacity, and soil nutrient pools, and thus poor soil health. Soil health comprises the biological, physical, and chemical properties of the soil that enable it to function as a living system and provide ecosystem services under current and changing conditions. To restore soil health and its associated functions, it is of prime importance to characterize and alleviate the main pressures that cause soil health decline. This can be achieved by using soil health indicators and their mechanistic links to each other and the functions they underpin. Next, interventions in soil management practices can be performed and the changes in soil health can be monitored. Farmers in the Global South are already employing various practices to enhance soil health which we discuss in more detail from an applied and soil health mechanism perspective. One such method is liming, which effectively raises soil pH and neutralizes soil exchangeable acidity. Another strategy is shifting cultivation, where farmers abandon a field and move to a new one, allowing the previous field to remain fallow and regenerate. Organic matter management has recently emerged as a crucial practice to improve soil health in the Global South. There has been a growing emphasis on shifting from conventional farming methods to conservation farming methods which help to bolster soil organic matter and improve various soil properties. Conservation farming principles such as minimum tillage, crop rotation, and growing of cover crops have proven to be effective in improving soil health. In order to further promote the improvement of soil health amidst the challenges faced in the Global South, a better understanding of suitable practices that conserve the soil and improve crop yields is needed.