塔里木河中游灰杨种群的径级结构与格局动态

Spatial distribution pattern and dismater structure of Populus pruinosa Schrenk population in the middle reaches of Tarim river

在新疆塔里木河中游轮台县胡杨林自然保护区内设置0.5hm2的样地,应用相邻格子法进行每木调查获取野外资料,研究灰杨种群径级结构和空间格局特征。结果表明:灰杨种群幼苗、幼树极度缺乏,中、大龄个体较多,其径级结构呈中间大、两头小的壶形,属衰退型种群,其生存发展前景堪忧。灰杨种群空间格局符合聚集分布,随发育进程其空间格局由随机向聚集型转变,大树阶段聚集强度逐渐减弱。种群不同发育阶段的空间分布格局差异与物种本身的生物、生态学特性有关,而且与物种的生境密切相关。

0.5hm^2 plots were established in natural Populus euphratica Oliv forest in the middle reaches of Tarim river, Luntai county, XingJing province and field data were obtained by investigating with contiguous grid quadrate method. The spatial distribution pattern and size class structure of Populus pruinosa were studied. The result showed resources of seedling and sapling were lack and media and large trees were abundant, Size class structure of P. pruinosa population was pot shape and belong to the type of declining population. It was weak ability in natural regeneration and has large difficult to live in the future. Spatial distribution pattern of P. pruinosa population conformed to clumped distribution. The distribution patterns of different development stages of P. prninosa population transformed from random to clumpe distribution with age development and aggregated intensity gradually decreasing in large tree stage. The differences of spatial distribution pattern at different development stages were closely related to ecological and biological characteristics of species and it＇s environment.