新疆艾比湖自然保护区阿奇克苏河沿岸胡杨年龄结构和生长量状况研究

利用在新疆艾比湖自然保护区阿奇克苏河沿岸设立的三块胡杨监测样地,根据4a来的实地观测数据对该区胡杨的年龄结构以及生长量情况进行了统计与分析。结果表明,该区胡杨年龄分布结构呈倒金字塔型,部分样地的Ⅰ～Ⅴ龄级胡杨甚至有缺失现象。在各龄级胡杨四年的生长量比较中,胡杨胸径和树高生长均随龄级的增加呈递减趋势,而冠幅生长则呈递增趋势。而在各样地胡杨的年平均生长量比较中,样地A1胡杨的胸径和冠幅生长均好于另两块样地,且差异比较结果显著(P<0.05),但各样地树高生长差异并不显著;结合各样地未缺失龄级(Ⅵ～Ⅺ)胡杨年平均生长量与林分密度、地下水位、土壤总盐含量、土壤pH值以及土壤有机物含量等生境因子进行相关性比较显示,胡杨胸径和冠幅生长量均与土壤总盐含量有高度相关性,地下水位则次之,而树高生长量与各生境因子相关性均不高。

The age structure and growth of Populus euphratica along the Aqikesu riverbank in Aibi Lake National Nature Reserve in Xinjiang

Three plots of Populus euphratica were established along the Aqikesu riverbank in Aibi Lake National Nature Reserve in Xinjiang,China.Age structure and growth of Populus euphratica were analyzed using the 4 years′field monitoring data.The results showed that the age structure of Populus euphratica was inverted pyramid shape and the Populus euphratica of age classⅠ～Ⅴeven turn up deletion in some plots.In comparisons of the 4 years’growth of Populus euphratica on every age class,although the growth of DBH and height were both decreased with the ages increase,the crown growth showed a tendency to increase.In comparisons of annual average growth of Populus euphratica among different plots,the growth of DBH and crown of Populus euphratica in plot A1 were better than that in plot A2 and plot A3,and the differences were statistically significant(P<0.05).On the contrary,the differences of growth of height were not significant among the three plots.According to the pearson analysis between the annual average growth of Populus euphratica(no absence of age class(Ⅵ～Ⅺ)) and habitat factors in each plot such as stands density,underground water level,total salt content,pH-value and total organic content,the growth of DBH and crown of Populus euphraticahad the highest correlation with total salt content,and to the underground water level there was weak connection.But the growth of height of Populus euphratica had a weak correlation with any habitat factor.