Soil is the sustainer of life. Neglect of the soil has led to vanished civilisations. Desertification, erosion, floods' saline lands are all the result of the neglect of the soil. Development of the fertility and usefulness of the soil are important if small farmers are to increase productivity. The most effective soil protection is carried out with the participation of the local community.
Trees and other vegetation also assist in soil formation. A significant contribution is the introduction of organic matter through litter formation and the decay and regeneration of tiny fibrous roots, both of which facilitate microbial activity. Another contribution is through the effects of root systems which break up soil and rock leading to, amongst other things, penetration of water. Root systems also bring mineral nutrients to the surface through root uptake. Organic matter formed by the decay of tiny fibrous roots can also bind with minerals, such as iron and aluminium, which can reduce the potential deleterious effects of these minerals on other vegetation.
Farmers have a tradition of treating and maintaining their soils with care and understanding. The terraces built on hill-slopes by tribal peoples in some areas are a tribute to their skilful handling of their soils. The use of bunds (small earthen dams) in rain-fed lands serves the dual purpose of checking erosion and producing fodder for livestock. Traditionally, farmers regard the soil as something sacred. They protect it and have devised techniques to save it. Almost every valley and gully are used to store water. The marginal lands of the lakes thus formed are reserved for growing fodder for the livestock of the village. This water was never meant for irrigation but as a percolation tank to raise the level of underground water below the bund. The landowners are free to dig wells and irrigate their fields. In the course of time the marginal lands were allotted for cultivation. The soil eroded and silted up the lakes. The quantity of water impounded was reduced and the underground water level was lowered. Production went down. These areas can be brought back to high production levels by introducing grass cultivation' agro-forestry and other soil building treatments. If they are not maintained properly today it is mainly because the farmer's lands are earning lower incomes.
Soil conservation and restoration of soil fertility have been accorded high priority in most countries. Implementation of these policies requires the understanding and participation of local people. This is made possible by education, and organization of effective services of the practitioner. The Soil Conservation Project in Kenya co-sponsored by the Ministry of Agriculture and the Swedish International Development Agency (SIDA) was started in 1974. According to one spokesperson for the project, Due to rapid population growth, people have been obliged to find new arable land by cutting trees and farming on steep slopes. This has led to land erosion which results in decreased yields and famine in some areas.