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By analyzing and comparing several concepts about vegetation coverage given by other specialists,several new threshold of vegetation coverage are put forward:the coverage allowed by ecology,the coverage demanded by ecology and the coverage allowed by economy,then the methods are given to calculate.

通过对已有的关于植被覆盖度的概念进行分析比较,提出几个新的植被建设覆盖度阈值生态允许覆盖度、生态要求覆盖度和经济允许覆盖度,并给出了它们的计算方法。