Soil conservation for small farmers in the humid tropics [antikvár]

FOREWORD Our existence depends laregly upon the thin layer of soil from which we produce most of our food, fibres and timber. If used for the right purpose, and managed well, soils can continue to produce and to provide for our needs indefinitely. But if put to the wrong use, and badly managed, soils can quickly degrade, decline in fertility and lose their potential to provide us with the things we need. Nowhere is this more so than in the humid tropics. In this region soils tend to contain most of their fertility in the top few centimetres of their profile. If these soils are exposed, and left unprotected from the frequent, high-intensity rainstorms which are common in the humid tropics, they can quickly erode, losing their fertile topsoil and leaving behind poor, infertile land. The humid tropics are important particularly as they are the home for many millions of small farmers. Most of these farmers are poor and many of them are forced to farm small plots of land on steep hillsides where the risk of erosion is at its greatest. For these people, the control of soil erosion is of the utmost importance - if their land is allowed to erode its fertility quickly falls, crop yields decline and the farmer may well be faced with the prospect of starvation or of migration to the slums of a city in search of work. In spite of the need, surprisingly few textbooks or manuals have been written specifically for the humid tropics, to help those people involved in practical problems of arresting soil erosion in this part of the world. FAO has therefore produced this Soils Bulletin as a reference for the planners and technicians working with small farmers in the humid tropics and who are searching for ideas and guidance in their efforts to overcome soil erosion and to introduce sustainable systems of productive agriculture.