胡杨、灰叶胡杨生物生态学特性调查

对胡杨、灰叶胡杨6个不同居群的分布、生境概况、生物学、生态学特性进行了调查，研究结果表明生境条件不同，居群的开花物候期、生长发育状况、花果产量、种子繁殖和营养繁殖以及群落的结构、繁茂程度等有所不同。地下水位在3～7m的居群，生长发育不良，种子繁殖和营养繁殖率很低，群落年龄结构老化，居群呈衰退趋势，影响因素是地下水位、土壤水分和土壤盐分的变化；地下水位在1．5～2．5m的居群，生长正常，花果产量高。胡杨、灰叶胡杨在所处各群落中均为建群种，群落垂直结构一般分为3层，群落水平结构的不郁闭性和林窗现象普遍。

Investigation on the characteristics of biology and ecology of Populus euphratica and Populus pruinosa

It was studies that geographic distribution,habitat, characteristics of biology and ecology of Populus euphration and Populus pruinosa in 6 different populations. The results indicated that abloom phenophase, growth and development extent,output of flower and fruit,seed propagation ,clonal propagation,the structure of community and luxuriant state of 6 different populations were different in different habitat.When water table level is from 3 to 7 m, growth of the population is bad,breeding rate of seed propagation and vegetative propagation wad very low,the age structure of community is ageing and population have the tendency of decline,influencing factor was changes in the water table level,soil moisture and soil salt.When water table level is from 1.5 to 2.5 m, growth of the population is normal,the output of fruit and flower is high. Populus euphration and Populus pruinosa were dominant species in various community,the vertical structure of community was divided into three layers,no closing and the phenomenon of floor window was universal in horizontal structure of community.