五脑山枳椇天然种群分布格局研究

Distribution Pattern of Natural Hovenia acerba Population in Wunaoshan Mountain

以麻城市五脑山枳椇天然种群为研究对象设置4块样地,采用相邻格子法进行每木调查,并采用Poisson分布拟合及χ^2检验等测度方式,对枳椇种群空间分布格局及聚集强度进行研究。结果表明:枳椇种群不同龄级植株均呈聚集分布;幼龄植株分布格局强度和种群聚集强度均高于中龄植株;随取样尺度的增大,种群分布格局升高,聚集强度下降,平均拥挤度上升;不同的取样尺度中,幼龄植株、中龄植株和全部种群植株分布格局均未出现分布拐点。

Four sampling plots were established in the natural population of Hovenia acerba to collect individual plant data by contiguous-grid quadrats method in Wunaoshan Mountain of Macheng City.The measures such as Poisson distribution fitting and chi-square test were used to evaluate the spatial distribution and aggregation intensity of Hovenia acerba population.The results showed that plants of Hovenia acerba population in different age groups were in aggregated pattern,the distribution pattern and population aggregation intensity of young plants were higher than those of middle-age ones,the aggregation intensity decreased but the distribution coefficient and the average crowding degree increased with the expansion of sampling areas,and that there were no turning points in distribution of young plants,middle-aged plants and all population plants at different sampling scales.