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永久農業
一個更全面性的方法是採用永久農業，它可以減少所有的農業投入，無論是水還是化肥。它是一個可持續發展的農業系統，以觀察自然體系和與自然協調發展為基礎，而不是與自然作對。它將動物養殖、節能效率、水利和節水技術融為一體。它強調種植多種不同的作物，而這些作物有不同的用處，其土地利用方式也不一樣。種植植物、飼養動物就是為了利用它們產生的肥料或自然殺蟲劑；動植物的殘骸及其動物的排泄物經過堆肥，重回土壤。蝸牛等害蟲也被收集拿來餵養鴨、鵝等家禽，而農田循著等高線開闢以利收集雨水，地面上也鋪蓋了草莖以減少水分蒸發。土地的多重目的利用使得這種耕作體系對洪水、火災以及蟲害有更強的抵禦能力。
永久農業的特殊做法因地制宜，它的基礎是觀察該如何適應當地的氣候、土壤和農耕背景。非洲有些傳統的農民採用他們所知的，現在被稱為「永久農業」的方式在耕種。波札那、南非、賴索托已採用了現代體系的永久農業方法。
水和能源的新來源
儘管需要額外的水或能量時，總該先檢驗需求管理，但水和能源的節約工作，不會總是排除掉對新資源供應的需求。要得到水或能量有很多可持續的方法，比起目前許多規劃者喜愛的大規模基建工程來，這些方法對生態系統和社區造成的損害會小些。並非所有這類的方法都能夠真的「替代」大型基礎建設，因為它們的產能比較小。
雖然大規模的工程並非總是最合適的選擇，但是這需要在全國和區域性的框架中，對能源開發、集水區管理的具體規劃進行評估。此外，下面描述的一些系統，已經或即將開始大規模的應用--譬如風能。這裏有些想法值得探索。
版權歸屬 國際河網IRN，環境資訊協會（陶俊 譯，李傑、李瑞玉 審校）
中英對照全文：http://e-info.org.tw/issue/water/2001/issue-water-irn01092401.htm
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Permaculture
A more comprehensive approach to reducing all agricultural inputs, from water to fertilizer, is to adopt the lessons of permaculture. This is a sustainable agricultural system based on observing natural systems and working with, rather than against, nature. It integrates animal husbandry, energy-efficiency, and water harvesting and conservation techniques. It emphasizes growing a variety of crops which offer different benefits and soil management. Plants and animals are grown for their fertilizer or because they produce natural pesticides; plant and animal waste is composted and put back in the soil. Pests such as snails are "harvested" to feed livestock such as ducks and geese, and the land is contoured to catch rainwater and mulched to reduce evaporation. Multipurpose use of the land helps makes the system stronger against floods, fires, and pests.
Permaculture's particular practices can vary from place to place, based on observation on what works for that climate, soil and cultural setting. Some traditional farmers in Africa practice their own version of what is now known as permaculture. The modern system of permaculture has been practised in Botswana, South Africa and Lesotho.
NEW SOURCES FOR WATER AND ENERGY
Although demand management should always be examined first when additional power or water is needed, conservation will not always preclude the need for new sources of supply. There are many sustainable ways to get power or water which cause less damage to ecosystems and communities than the large-scale infrastructure projects currently in favor with planners. Not all options can truly serve as "alternatives" to large infrastructure projects because their capacity is substantially smaller.
Large-scale projects are not always the most appropriate option, however - but this needs to be evaluated in the context of nationwide and regional planning for energy development and catchment management. In addition, some of the systems described below already have or are beginning to have large-scale application - wind power, for example. Here are some ideas worth exploring.
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