塔里木河下游荒漠河岸林不同退化区胡杨种群结构和空间分布格局研究  

Population Structure and Spatial Distribution Pattern of Populus euphratica in Degradation Regions of Desert Riparian Forest

作　　者：李吉玫[1,2] 徐海量[1,3] 张青青[1,2] 杨红梅[1,2] 牛俊勇[1,2] 赵新风[1,2] 库尔班.克依木 

机构地区：[1]中国科学院新疆生态与地理研究所,新疆乌鲁木齐830011 [2]中国科学院研究生院,北京100049 [3]中国科学院绿洲生态与荒漠环境重点实验室,新疆乌鲁木齐830011 [4]塔里木河流域管理局,新疆库尔勒841000

出　　处：《中国沙漠》2009年第5期897-904,共8页Journal of Desert Research

基　　金：国家自然科学基金项目(4067103630600092)资助

摘　　要：对塔里木河下游荒漠河岸林退化程度不同的4个典型断面胡杨种群结构和空间分布格局进行了研究,结果表明:①胡杨种群密度从英苏断面的8.01株/(25 m×25 m)下降至依干不及麻断面的0.62株/(25 m×25 m),同时伴生种数量和种类不断减少。②胡杨种群整体分布不均匀,幼苗和小树缺乏,中龄和老龄植株所占比例较高。随着退化程度的加剧,幼苗和小树所占比例不断降低,而中龄和老龄植株所占比例明显增加。③胡杨种群整体分布格局为聚集分布,聚集度Moristia指数Iδ从英苏断面的1.67增至依干不及麻断面的4.99,并且幼苗和小树发育阶段的胡杨种群分布格局因植株数量的不断减少,逐渐由聚集分布过渡为随机分布,而中龄和老龄发育阶段的胡杨种群均为聚集分布。④影响胡杨种群结构和分布格局变化的主要因子是地下水埋深,浅层土壤含水率对其影响不大。The study on population structure and spatial distribution pattern of P. euphratica was conducted in degradation regions of desert riparian forest at lower reaches of Tarim River, Xinjiang. The results showed that the population density followes a tendency of decreasing with the degradation level, with the greatest decease at the level from heavy degradation region to extremely degradation region. Meanwhile the number of accompanying species in the P. euphratica plot decreases with the increasing level of degradation. The distribution of the P. euphratica population was uneven. There relatively lack seedlings and saplings, but middle tree and old tree are rich. Individual P. euphratica population formed different distribu- tion patterns under different environment conditions. Along with the degradation level increasing, the number of seedling and sapling of the P. euphratica population decrease, but the number of the middle and old tree increase. The distribution pattern of the P. euphratica population was generally in cluster, and the aggregation intensity increased with the degradation level increasing. The distribution pattern of the seed- lings and saplings shifted from cluster to random. It is groundwater depth other than the shallow water content of soil that influences the structure and distribution pattern of the P. euphratica population.

关 键 词：荒漠河岸林 胡杨种群结构 分布格局 地下水埋深 浅层土壤含水率 塔里木河下游 

分 类 号：Q948.5[生物学—植物学]