Erosion prevention and maintenance of soil fertility

Reversing the degradation of soil, water and biological resources are essential components in achieving food and livelihood security. Symptoms of soil degradation are numerous and include decline of soil fertility, development of acidity, salinization, alkalization, deterioration of soil structure, accelerated wind and water erosion, loss of organic matter and biodiversity. As a result, socio-economic impacts include that farm labour productivity and revenues from agriculture are falling, migration to urban areas is increasing and rural poverty is exacerbated. Efforts to restore productivity of degraded soils must be coupled with other measures that affect the land use practices - in particular conservation agriculture, good agricultural practices and irrigation management and integrated plant nutrient management.

Animal excreta can be an important source of nutrient and maintain soil fertility in grazed grasslands and croplands, especially in developing countries. Globally, about 15 percent of the N applied to crops comes from livestock manure. Conversely, livestock can cause soil erosion and degradation as a combination between over grazing, pedo-climatic factors, and other management practices (fire suppression, clear cutting). Livestock exclusion, rotational or rational grazing can be necessary to avoid soil degradation or promote their restoration.

Fish are important for the maintenance of sediment processes and proper spatial planning and integrated systems in fisheries and aquaculture, for example, can work to minimize soil erosion along rivers, lakes and coastal areas.

Studies have shown that the more closely an agricultural system resembles a natural forest in its canopy structure, tree spacing and ground cover, the less chance there is of soil erosion. Traditional agroforestry techniques, which provide natural cover, have been used for centuries to produce food without causing long-term damage to the environment.