World Soil Erosion and Conservation: Soil erosion and conservation in West Africa
World Soil Erosion and Conservation: Soil erosion and conservation in West Africa
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世界土壤侵蚀与保护：西非的土壤侵蚀与保护
DOI：
10.1017/cbo9780511735394.003
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
R. Lal
中科院分区：
文献类型：
--
作者：
R. Lal
在本章中，西非被定义为位于北纬18度至北纬18度、东经30度之间的区域。该地区的年降雨量在300至3000毫米之间，在一个或两个不同的季节。淋溶土是西非稀树草原地区的主要土壤，降雨量为800至1500 mm。西非淋溶土来源于结晶酸性岩石和基底复合体，通常以浅层砾石层为特征。这些土壤的表层质地粗糙，极易被水压实和侵蚀。大约60%的西非稀树草原被淋溶土覆盖。干燥气候（年降雨量300-800毫米）的土壤主要是干旱土、初成土和淋溶土。这些土壤也容易受到加速侵蚀。腐植土和氧化土出现在西非的高降雨量（年降雨量> 1500毫米）地区，即象牙海岸、利比里亚、塞拉利昂、尼日利亚东部和喀麦隆的沿海地区。非洲中部的一些土壤现在被归为氧化土，实际上可能是腐植土。氧化土是赤道地区的主要土壤，年降雨量超过2 000毫米。西非土壤的生产潜力很低，因为固有肥力低，植物可用水储量低，降雨量多变和不稳定，以及严重的侵蚀和侵蚀引起的退化。
In context of the present chapter, West Africa is defined as the region lying between 0 N, 18 E and 18 N, 30 E. The region has an annual rainfall ranging between 300 and 3000 mm received in one or two distinct seasons. Alfisols are the predominant soils of the West African Savanna region with a rainfall of 800 to 1500 mm. The West African Alfisols are derived from crystalline acid rocks and basement complex and are usually characterized by a gravelly horizon at shallow depths. These soils have a coarse-textured surface horizon and are highly prone to compaction and erosion by water. About 60% of the West African Savanna is covered by Alfisols. Soils of the drier climate (300-800 mm annual rainfall) are mostly Aridisols, Inceptisols, and Alfisols. These soils are also susceptible to accelerated erosion. Ultisols and Oxisols occur in high rainfall (> 1500 mm annual rainfall) regions of West Africa, ie the coastal areas of the Ivory Coast, Liberia, Sierra Leone, eastern Nigeria and Cameroon. Some soils of central Africa now classified as Oxisols may, in fact, be Ultisols. Oxisols are predominant soils of the equatorial zone with high annual rainfall exceeding 2000 mm. Productivity potential of soils of West Africa is low because of low inherent fertility, low plant-available water reserves, variable and erratic rainfall, and severe erosion and erosion-caused degradation.