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經納米比亞沙漠研究基金會Desert Research Foundation of Namibia）同意再版〈〈共用非洲南部的水〉〉(Sharing Water of Southern Africa)（1997）。欲獲得更多關於DRFN的資訊，請參見聯絡處，欲知更多關於本書的內容，請參見資料來源。
關鍵問題
▲景觀 (註1) 提供了人類賴以生存的自然資源--水，動物，土壤，農作物，木材，燃料木，(在非洲南部)卻變成了貧瘠的沙漠。
▲非洲南部的降雨特點是，夏季的降雨量比較多，一般地區的降雨量低於夏季的降雨量。除了在好望角 (The Cape）一帶有冬雨。該地區比較乾燥的地區，降雨量、降雨時間和降雨強度的變化非常大。乾旱經常、而且隨時都可能發生。
▲水在海洋、湖泊、地表、和地下間循環。雖然水是不斷地循環，但可利用的水卻是有限。雖然人們常常將水從過剩地區調到不足地區，但要想"從這個體系"得到更多的水是不可能的（除非是將海水進行脫鹽處理）。
▲。由於水的蒸發和蒸騰作用，非洲南部損失了大量的水。人們直接取用的水循環中僅剩的少量淡水，而這些水儲存於靠降雨增長的河川和地下水源。
▲影響地面水的因素也同時影響到空氣中、地表和地下水的質量和數量。人類活動，如商用林業，養殖過多家畜導致過度放牧和土壤侵蝕，污染河流或地下水的使用速度比其再補充速度更快，所有的一切都影響著體系中每個部分水的可用性。而下游地區的水質水量完全依靠於水在上游是如何被使用或濫用的。
▲就地區能維持其生存的植物、動物和人類的數量和種類來講，濕地是非常富裕的地區。濕地是自然灌溉系統，當地的降雨，偶而的乾旱和洪澇等自然條件和生存在那裏的動物、植物處於一種協調的狀態。濕地應該以一種不破壞其動態模式的方法加以利用。
版權歸屬 國際河網 環境信託基金會(金霞 譯，李堅、陳維立審校)
中英對照全文：http://news.ngo.org.tw/issue/water/issue-water-irn00100901.htm
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Reprinted with permission from Sharing Water in Southern Africa by the Desert Research Foundation of Namibia (1997). See Contacts for more information on DRFN and Resources for more on this book.
KEY ISSUES
▲ The landscape hosts the natural resources on which people depend: water, animals, soils. crops, timber, fuelwood, becomes a barren desert.
▲ Southern Africa is characterized by low to fairly good rainfall that falls in the summer, except in the Cape where there is winter rain. Variation in the amount of rain and its timing and intensity during the season are great, especially in the drier parts of the region. Droughts are frequent and can strike at any time.
▲ The water cycle circulates water between the oceans and lakes, the air, the land surface, and underground. Although water is constantly in circulation, the amount that is available is finite. It is impossible to get more "out of the system" (except by desalination of sea water), although transferring water from an area of surplus to an area where there is a shortage is frequently done.
▲ Southern Africa experiences very high losses of water from evaporation and transpiration, with the result that only a very small proportion of the total rainfall enters streams or groundwater reserves, where it is available to be used directly by people.
▲ What happens to water on land affects the quality and quantity of water in the air, in surface water bodies and underground. Human activities such as commercial forestry, keeping too many livestock that causes overgrazing and soil erosion, polluting rivers or using groundwater faster than it can be recharged, all have consequences on water availability elsewhere in the system. Downstream areas are dependent on how water is used or abused upstream.
▲ Wetlands are extremely rich areas in terms of the numbers and diversity of plants, animals and people they can support. They are natural irrigation systems that have formed in harmony with the local conditions of rainfall, occasional droughts and floods, and the animals and plants that they support. They should be used in ways that do not disturb the dynamic pattern.
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