略谈水土保持科学体系

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水土流失对自然资源惊人的破坏作用,已日益为世人所关注。据联合国开发计划署估计,由于土壤侵蚀,全世界每年要丧失可耕地500—700万公顷;到本世纪末,有可能上升到1,000万公顷。我国960万平方公里土地中,水力侵蚀显著和风蚀严重的沙化面积共约280万平方公里,占总土地面积的29.2%。因此,侵蚀问题已被认为是遍布世界各国的重要公害之一。为了有效地控制侵蚀,本世纪以来,对于侵蚀规律及其防治措施和途径的研究,在许多国家相继展开。几十年来,国内外都已取得了大量研究成果。一门新的应用科学——水土保持学,实际上已初步形成。几十年来,我国对于水土保持科学研究和水土保持治理工作的方针和重点,曾展开过热烈的讨论。因提法上曾有过不少次变更,以致在工作上也出现过许多不必要的反复,造成严重的损失,时至今日,仍未得出统一、明确的结论。究其原因,主要是对水土保持的研究任务、研究内容以及与其他有关学科的关系不够明确。这就是我们探讨水土保持科学体系的历史背景。我们认为,为了推进中国水土保持工作的发展,首先必须明确水土保持学科的几个主要问题。一、水土保持学的主要研究任务是: 1、揭示水土资源的破坏及其保护、开发与利用的规律性; The astonishing destructive effect of soil and water loss on natural resources has become increasingly of concern to the world. According to the United Nations Development Program, due to soil erosion, the world will lose 5 to 7 million hectares of arable land every year. By the end of this century, it may rise to 10 million hectares. Of the 9.6 million square kilometers of land in China, a total of 2.8 million square kilometers of sandy areas with significant water erosion and serious wind erosion are accounted for 29.2% of the total land area. Therefore, the issue of erosion has been considered as one of the most important public hazards all over the world. In order to control the erosion effectively, the research on erosion law, prevention measures and ways has been carried out in many countries since the beginning of this century. For decades, a great deal of research has been made both at home and abroad. A new applied science - Soil and Water Conservation, has actually taken shape. In the past decades, there have been heated discussions in our country on the guidelines and priorities for soil and water conservation scientific research and soil and water conservation. There have been many changes in the formulation of reference so that there have been many unnecessary repetitions in the work which have caused serious losses. Up to now, no uniform and definite conclusion has yet been reached. The reason is mainly the research task of soil and water conservation, the content of the research and the relationship with other related disciplines are not clear enough. This is the historical background of our discussion of the scientific system of soil and water conservation. In our opinion, in order to promote the development of soil and water conservation work in China, we must first clarify a few key issues of the discipline of soil and water conservation. First, the main research tasks of soil and water conservation science are: 1. Reveal the destruction of water and soil resources and the regularity of their protection, development and utilization;
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