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通过样地调查和数据统计,对塔里木河流域不同生境内胡杨种群的径级结构、年龄结构、生命表及存活曲线进行了比较分析。同时,使用种群动态量化方法定量的分析了胡杨种群数量的动态变化。结果表明,由于生境条件的不同,胡杨种群结构存在着差异性,尤其是下游胡杨种群与上、中游种群的差异性较大。上、中游胡杨种群的幼苗丰富,种群径级大小、年龄结构均呈金字塔型,存活曲线符合DeeveyC(凹)型,且其动态指数均大于0,为增长型种群;而下游胡杨种群的幼林株数(10 a以内)较少,长势较差,出现很多枯死幼树,种群结构属于中部大,两端小的偏正态分布,存活曲线呈现凸型,且其动态指数小于0,为衰退型种群。
Through the field survey and data statistics, the diameter structure, age structure, life table and survival curve of Populus euphratica populations in different habitats in the Tarim River Basin were comparatively analyzed. At the same time, the population dynamics quantitative method was used to quantitatively analyze the population dynamics of Populus euphratica. The results showed that Populus euphratica population structure was different due to different habitat conditions, especially Populus euphratica Populus population and the upper and middle reaches populations. The Populus euphratica population in the middle and middle reaches was rich in seedlings. The population size and age structure of the Populus euphratica population was pyramidal, and the survival curve was in accordance with DeeveyC (concave) type. The dynamic indices were all larger than 0, (Less than 10 years), the growth was poor, many young and dead trees appeared. The population structure belonged to the large central part and the small extremes in the central part. The survival curve was convex and its dynamic index was less than 0, which was the decaying population .