新疆阿尔泰山前平原河谷林植被类型

A VEGETATIONAL SURVEY OF VALLEY FORESTS IN THE PEDIMENT PLAIN OF ALTAI DISTRICT OF XINJIANG

在新疆阿尔泰地区山前平原,沿河谷发育着带状的、以杨属树种为主的森林。本文将该河谷林划分为8个群系和16个群丛组,并作了较详细的描述。所记载的杨属种类有苦杨、银白杨、银灰杨、黑杨、额河杨、胡杨和灰胡杨等7种,此外还有疣枝桦、尖果沙枣以及柳属的几个树种(白柳、三蕊柳等)。河谷林出现在半荒漠、荒漠等地带性植被的包围中,无疑是河谷特殊生境的产物,它对河谷环境和农牧业发展有重要意义。

In the pediment plain of Altai District of Xinjiang, the temperateforest dominated by species of Populus, develop along the river-valleys.Eight formations and sixteen association groups are described in somedetail by this paper, and their distribution is also briefly discussed.Among the tree species recorded in the river-valleys, seven belong to thegenus of Populus(P. laurifolia, P. alba, P. canescens, P. nigra, P.jrtyschensis, P. euphratica and P. pruinosa ), the others are Betula pendula,Elaeagnus axycarpa and a few species of Salix (S.alba, S.triandra etc.).In the area where the vast land is covered by the zonal semi-desert anddesert vegetation, the particular environmental conditions of the river-val-ley are responsible for the presence of these forests. which play signi-ficant role on the environment, agriculture and animal husbandry of thearea.