Soil Cons
This is the VOA SpecialEnglish Agriculture Report.
Soil conservation efforts protect soil from wind and water thatcan blow or wash it away. Good soil produces food crops for bothhumans and animals.
One important form of soilconservation is the use of windbreaks. Windbreaks stop the wind fromblowing soil away. They also keep the wind from destroying ordamaging crops.
Windbreaks are barriers formed by trees and other plants withmany leaves. Farmers plant windbreaks in lines around their fields.They are very important when grains such as wheat are grown.
For example, in parts of West Africa, studies have shown thatgrain harvests can be twenty per cent higher on fields protected bywindbreaks compared to those without such protection.
Windbreaks are effective when a wall of trees and other plantsblocks the wind.
The windbreaks should also limit violent motions of the wind tothose areas closest to the windbreak.
Windbreaks seem to work best when they allow a little wind topass through. If the wall of trees and plants stops wind completely,then violent air motions will take place close to the ground. Thesemotions cause the soil to lift up into the air where it will beblown away. For this reason, a windbreak is best if it has onlysixty to eighty per cent of the trees and plants needed to make asolid line. An easy rule to remember is that windbreaks can protectareas up to ten times the height of the tallest trees in thewindbreak.
There should be at least two lines in each windbreak. One lineshould be large trees. The second line, right next to it, can beformed from shorter trees and other plants with leaves.
Windbreaks not only protect land and crops from the wind. Theycan also provide wood products. These include wood for fuel andlonger pieces for making fences. Locally-grown trees and plants arebest for windbreaks.
You can get more information about windbreaks and other forms ofsoil conservation from the group Volunteers in Technical Assistance.VITA is an organization that helps people around the world usescience and technology to solve problems.
You can contact VITA through the Internet at its World Wide Webaddress, w-w-w dot v-i-t-a dot o-r-g.
This VOA Special English Agriculture Report was written by GaryGarriott.