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研究林木病害在自然环境中的空间分布型有助于揭示出病害种群的扩散和流行规律,还可以利用空间分布型的信息进行精确有效的抽样设计。杉苗猝倒病是杉木苗期的重要病害之一,近年来我市每年发生5,000多亩,给杉苗带来了较大损失。1984年5月,我们对春播和秋播杉苗猝倒病的空间分布型进行了研究。本文用三种理论频次分布和几种聚集度指标确定了杉苗猝倒病空间分布型。一、研究方法(一)调查方法
Studying the spatial distribution of tree diseases in natural environment can help to reveal the spread and epidemic rules of diseased populations. It can also use the spatial distribution of information for accurate and effective sampling design. Seedling damping-off disease is one of the most important diseases of Chinese fir seedling. In recent years, 5,000 mu have occurred in our city every year, which brings great losses to the seedlings. In May 1984, we studied the spatial distribution of spring-sowing and autumnal fir seedling damping-off. In this paper, three kinds of theoretical frequency distribution and several indicators of the degree of aggregation to determine the spatial distribution of Cunninghamia lanceolata disease. First, the research methods (A) survey method