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Erosion control in the tropics - Part 5

5 Agronomic methods to control erosion Agronomic methods include those erosion control measures that are related to arable farming. It is concerned with crop cultivation itself as well as tillage operations. Arable farming is an integral part of the natural surroundings. | 5 Agronomic methods to control erosion Agronomic methods include those erosion control measures that are related to arable farming. It is concerned with crop cultivation itself as well as tillage operations. Arable farming is an integral part of the natural surroundings. Woodland and grassland influence arable farming. Think of the cattle pastures where manure will again benefit the soil. The felling of trees and the planting of trees also strongly influence the cropping system. All this is called a farming system. We will treat this in more detail in Chapter 6. Agronomic measures play a key role in erosion control because in the first place they can be carried out relatively easily and cheaply. Moreover often results are obtained quickly and if it is still found necessary to take technical measures they contribute considerably to their success see Chapter 7 . In this chapter we will give a survey of the most important agronomic measures. The principles of these measures are given in Chapter 3 and should be clear. Contour farming and strip cropping aim at preventing water to run off and at retaining the rain water. Minimum tillage mulching and the use of a cover crops serve to protect the soil against the force of the rainfall at the same time maintaining the soil fertility or increasing it. Manuring has the role of keeping the crop in good condition so that it can stand up to erosion better. Finally mixed cropping aims at good crop growth with optimal use of available light water and nutrients. This minimizes the chance of erosion. 30 Erosion control in the tropics Of each measure principles and execution are treated as well as drawbacks. Too detailed advice of course cannot be given for the execution you will have to find out for yourself whether and how certain procedures can be carried out best in your local situation. Mixed cropping for example will require a suitable combination of crops. Consultation with the local population and institutions is important .