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机构地区:[1]河南省汝南园林学校,河南汝南463300 [2]河南农业大学,河南郑州450002
出 处:《河南农业大学学报》1999年第S1期33-37,共5页Journal of Henan Agricultural University
摘 要:对豫南马尾松人工同龄纯林株数累积分布进行了研究,建立了4 种数学模型———logistic 曲线、三次、四次、五次回归方程,并对拟合结果进行了比较。结果表明:这4 种模型都取得了满意的结果,但以五次多项式回归方程更佳。Based on the research on trees accumulating distribution of Masson Pine even-aged and pure plantation stand in South Henan,four types of maths model,including logistic curve,third,fourth and fifth power of statistics regression equation,have been established and compared.The fitting results show the fifth power of multinomial statistics regression equation is the best model while the four types of maths model are satisfying and reasonable.It can describe the law of trees accumulating distribution of Masson Pine even-aged and pure plantation forest in South Henan correctly and precisely.
关 键 词:马尾松 人工林 株数累积分布 logistic曲线 五次多项式
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