结果表明：各种植被类型中物种数与个体数对数成线性关系是一种普遍现象，且不受调查树木的径木级影响。

The results indicate that the rate of species accumulation is related to the logarithm of number of individuals in each vegetation type, independent of diameter classes.

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栎类次生林乔木的密度随高度级、径级的增加而递减，但树种丰富度却不随树木的密度增加而增加。

Tree density in the forest decreased with the increases of height class and diameter class, whereas species abundance did not increase.

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常绿阔叶林内不同高度级、不同径级和不同样方斑块内的树种数都与树木密度呈显著的正相关关系。

There was a significant positive correlation between tree species abundance and tree density for trees of different height classes.

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