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本文将山海关林场的油松－槲树林划分为５种类型，并对各种类型的种群空间分布格局、年龄结构、胸径结构、树高结构等进行了研究。结果表明：槲树幼树分布格局为聚集分布；油松幼树只存在于郁闭度不超过０．７的油松林分中，其分布格局偏离聚集分布。油松和槲树混交时，次要树种林木常呈聚集分布，优势树种林木呈随机分布。以年龄结构表示的林木发生过程显示，油松先发生，槲树后发生，但有时两树种的年龄结构是隔离的，有时是略有重叠的。油松的树高和胸径结构呈山形分布，槲树往往呈倒Ｊ形，这表示了两树种在演替中的地位。
In this paper, the Pinus tabulaeformis-Quercus mongolica forest in Shanhaiguan forest farm is divided into five types, and the spatial distribution pattern, age structure, DBH structure and tree height structure of various types of population are studied. The results showed that the distribution pattern of young trees was clustered; the young pine tree was only found in Pinus tabulaeformis forest with its closed degree not exceeding 0.7, and its distribution pattern deviated from the aggregation distribution. When Pinus tabulaeformis and Quercus hybrids were mixed, the secondary tree species often aggregated and distributed, and the dominant tree species distributed randomly. The occurrence of forest trees in the age structure shows that Pinus tabulaeformis first occurs after the tree, but sometimes the age structure of the two species is isolated and sometimes slightly overlapped. The tree height and DBH structure of Pinus tabulaeformis was distributed in a mountainous pattern, and the tree was often inverted J-shaped, indicating the status of two tree species in succession.