|Soil Conservation Techniques for Hillside Farms (Peace Corps, 1986, 96 p.)|
|Soil conservation strategies|
1. Protecting Native Vegetation
Ideally, the environmental damages associated with agricultural activities could be avoided by protecting the native vegetation, which keeps the problem from arising. This method, however, ignores man's dependence on traditional agricultural techniques to support himself and is difficult to promote, especially as human populations increase. This strategy does however, provide other valuable benefits such as maintaining a clean, reliable supply of drinking water, and reserves for native fauna and flora, which also become increasingly important as the human population increases.
2. Replanting Native Vegetation
In view or the benefits of native vegetation, replanting of previously cleared land can be an effective method for protecting land, water supplies, and native wildlife. (Fig. 5)
Reforestation (or replanting of grasses or shrubs, depending on natural vegetation type) can be carried out using native species or introduced species adapted to the local conditions, having some desirable characteristic (fast growth rate, the ability to fix nitrogen, forage or wood value, etc ), and which will facilitate the return of a protective vegetative canopy A description of some species is given in Firewood Crops Shrub and Tree Species for Energy Production (N.A.S. ,
Fig. 5. Reforestation
3. Perennial Crop Cultivation Systems
Another technique which results in a minimized soil disturbance is the planting of perennial crops, such as fruit trees or pasture grasses, rather than annual crops such as corn or beans. In this manner, after the initial disruptive clearing and planting of the land a permanent ground cover is attained and the environmental damages associated with the raindrop impact are lessened. (Fig. 6).
Fig. 6. Perennial Crops - Fruit trees and pasture grasses
4. Use of Ground Cover while Cultivating Annual Crops
There are techniques for maintaining a protective ground cover even while cultivating annual crops. These include minimum tillage and mulching systems. In minimum tillage systems, only the narrow row where the seeds are planted is tilled and the remaining ground surface is left intact. Because these intact areas are more compacted and have a law weed covering, they are more erosion resistant.(Fig. 7) Mulching is the use of dead material or the planting of a ground cover which results in a covering of the bare soil areas in a field. As in the other techniques, the covered soil is less susceptible to erosion than bare soil. In the section on "Green Manure Crops" some suggestions for using legume cover crops are presented.
Fig. 7. Minimum tillage cultivation system