Erosion control in the tropics - Part 8 pptx

... Underlying causes of erosion 73 8 Underlying causes of erosion In the previous chapters we have seen how the chance of erosion can be lessened by taking certain precautions. However, ... yourself why erosion occurs in a certain area. Not only will the deeper causes of erosion be found in the socio-economic backgrounds, but the incentive will be found which mot...

Ngày tải lên: 02/07/2014, 05:20

... 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 ... grassland influence arable farm- ing. Think of the cattle pastures where manure will again benefit the soil. The felling of trees and the planting of trees also stron...

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... drain The main drainage serves as the main channel where all the water is collected. ? One main drain at the bottom of the catchment area: all the col- lected water ends up in the main drain ... crops, Erosion control in the tropics 68 The purpose of gully control is not so much erosion control as an at- tempt to limit the effects of erosion that i...

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... especially inflorescences; they can ruin even a heavy bloom. Control using insecticides is diffi- cult and depends on correct timing at the beginning of the flush. This is only possible if all the ... extent by cutting out and burning affected branches before the end of the dry season, so that there are few sources of infection at the beginning of the rains. Mango hoppe...

Ngày tải lên: 02/07/2014, 00:20

... an insight into the causes and the course of the erosion process, by stating the factors which influence the mechanism of erosion and how these factors are linked up. Introduction 9 If the ... erosion here. There are really two types of erosion, natural and accelerated erosion, also called man-made ero- sion. ? Natural erosion is going on all the time; the weat...

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... clear that when observing the erosion phenom- ena, the important thing is always to trace the causes of it. In the fol- lowing chapters we will go more deeply into the erosion process, which ... keep the course of the erosion process in mind when looking for signs of erosion in the field. When a certain characteristic is no- ticed, one should ask oneself just w...

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... Erosion control in the tropics 20 Organic matter content of the soil Organic matter probably is the most important factor in binding the soil particles. The better the soil particles ... of erosion is likely to occur. 3.1 Splash -erosion and stream -erosion Within water -erosion there are two types of erosion: splash erosion and stream erosion. Certainly...

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... Erosion control in the tropics 28 Removing this soil from the drainage system or the paths adds to the workload of the farmer. ? The reverse applies of course to the field where the soil ... labour and the farmer is obliged to sow up a smaller area for in- stance. ? When thin layers of soil are continually washed away from the field by erosion, the big...

Ngày tải lên: 02/07/2014, 05:20

... again. Burning is an integral part of cattle farming in the tropics and improvements in the technique must be found. The timing and the method of burning seem to determine whether it is damaging ... drinking places and in doing so they trample down the soil. During rain showers water collects in the trampled tracks (the rain does not necessarily affect the str...

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... underestimated. Erosion control in the tropics 76 9.2 Awareness Only if people appreciate the usefulness of the operations to be carried out, will they be inclined to take them up themselves. They should ... concerned or the well-intentioned development worker ei- ther. Sometimes the causes can only be tackled by political influence among the people themselves, a p...

Ngày tải lên: 02/07/2014, 05:20