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从油松分布区不同部分的56个天然林分中,采集针叶、球果和种子样本,测定了18个特征。经统计测验表明,这18个特征林分间的差异是高度显著的。有些特征与气候条件的相关性也很强。总的趋势是:气候越干旱寒冷,针叶越短越宽,球果和种子越大。但在西部地区,在球果和种子方面与上述一般趋势有偏离。各种特征的变异主要发生在两个方向上,即同经度下的纬度变异和沿整个分布区长轴由西南经中部地区到东北方向的变异。
From 56 natural stands in different parts of Pinus tabulaeformis, coniferous, coniferous and seed samples were collected and 18 characteristics were determined. The statistical tests showed that the differences among the 18 characteristic forests were highly significant. Some features are also highly correlated with climatic conditions. The general trend is: the drier the climate is, the shorter and wider the needles are, and the bigger the cones and seeds are. However, in the western region there is a departure from the above general trend in cones and seeds. Variation of various features occurs mainly in two directions, that is latitude variation with the longitude and variation along the long axis of the entire distribution from the southwest through the central region to the northeast.