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环境退化并非新问题,大约从七千年前人类开始开垦和耕作土壤以来,就已面临土壤侵蚀和盐碱化等问题。在20世纪30年代美国及其他国家对土壤侵蚀的关心,促进了土壤保持的发展。从此,人们投入了大量的财力和物力,试图克服土壤退化的问题,但是,尽管如此,所获成效一直令人失望,今天仍有很多类似问题。我们为什么不能成功地克服土壤退化问题呢? 为了回答这个问题,必须对目前土壤保持方法进行分析。 现在涌现出的土壤保持新方法与老方法有两点不同:一是进一步强调了土地利用不合理和管理不善的根本原因;二是现在土壤保持专家试图建立的技术和方法,不仅是为了防止土壤退化,而且能为农民提供直接短期利益。
Environmental degradation is not a new problem. Since human beings began to cultivate and cultivate soil about seven thousand years ago, they have faced such problems as soil erosion and salinization. Concern about soil erosion in the United States and other countries in the 1930s led to the development of soil conservation. Since then, people have invested a great deal of financial and material resources in trying to overcome the problem of soil degradation. However, the results achieved have been disappointing. There are still many similar problems today. Why can not we successfully overcome the problem of soil degradation? In order to answer this question, we must analyze the current soil conservation methods. The emerging new approaches to soil conservation now differ from the older ones in two ways: one is to further emphasize the underlying causes of irrational and mismanaged land use; and second, the technologies and methods that soil conservation experts are now trying to establish, not only to prevent soil Degradation, but also provide immediate short-term benefits to farmers.