摘要
在新疆塔里木阿瓦提县天然胡杨林内设置50 m×50 m标准样地1块,应用相邻格子法进行野外调查获取资料.应用方差/均值比的t检验法、聚集强度指数和理论分布模型对胡杨林主要种群空间分布格局与动态进行研究.结果表明:乔木层的2个优势种群空间分布均呈聚集分布,胡杨种群的聚集强度大于灰叶胡杨;灌木层的2个伴生种群也均呈聚集分布,柽柳的聚集强度较大;草本层中甘草种群呈聚集分布,西北天冬呈随机分布.Taylor幂法则、Iwao m*对X的回归模型均显示胡杨、灰叶胡杨种群呈聚集分布.灰叶胡杨在不同发育阶段的空间格局均呈聚集型,随发育进程其聚集强度逐渐减弱.胡杨种群不同发育阶段呈随机→聚集→随机分布.不同种群和不同发育阶段的空间分布格局差异与其生态生物学特性和种群间的竞争排斥有关,而且与物种的生境密切相关.
One 50 m × 50 m standard plot was sampled in natural forest of Populus euphratica in Awati County, which is situated at the edge of Tarim Basin, Xinjiang Uygur Autonomous Region, and the field investigation was conducted with contiguous grid quadrate method. By means of t - test of variance/mean value ratio, aggregation intensity index and theoretical distribution models, the spatial distribution pattern and the dynamics of primary populations in P. euphratica forest were studied. The results showed that the spatial distribution pattern of two dominant arbor populations conformed to clumped distribution. The aggregation intensity of P. euph- ratica population was higher than that of P. pruinosa population. The spatial distribution pattern of two companion plant populations in the shrub layer also conformed to clumped type, though the aggregation intensity of Tamarix chinensis was higher. In the herb layer, the distribution patterns of Glycyrrhiza uralensis and Asparagus persicus conformed respectively to clumped pattern and random pattern. The tested results of Taylor power method and Iwao＇s M - ^-X regression model also verified that both P. euphratica and P. pruinosa populations belonged to clumped pattern. Although the distribution pattern of P. pruinosa population at different development stages all belonged to clumped distribution pattern, the aggregation intensity dropped gradually along with age development. The distribution patterns of P. euphratica population at different development stages changed from random type to clumped type, and further to random type. The differences in spatial distribution pattern of different populations at different development stages were related not only to ecological and biological characteristics of each species in the communities in the light of competitive exclusion principle among the populations, but also closely related to the habitats in which the species lived in.
出处
《西南林学院学报》
2007年第2期1-5,10,共6页
Journal of Southwest Forestry College
基金
新疆生产建设兵团塔里木盆地生物资源保护利用重点实验室开放基金(BR0603)资助项目
塔里木大学校长基金(TDZKSS05008)资助项目
关键词
胡杨群落
种群
空间分布格局
聚集强度
动态格局
Populus euphratica community
population
spatial distribution pattern
aggregation intensity
dynamic pattern
