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机构地区:[1]甘肃农业大学草业工程系
出 处:《甘肃农业大学学报》1994年第4期423-427,共5页Journal of Gansu Agricultural University
摘 要:本文通过对一个温带-针阔叶林草原生态系统的调查研究得出,在人类强烈的生给活动影响下,山地针-阔叶林被的演替依坡向、坡度和海拔高低呈如下序谱:在北向坡,原Paatstabulae-formis—Sinarundinarianitida群落由高而低依次变为Betulaalbo-sinensis-Sinarundinarianitida,B.platyphylla─Populusdavidiana,Quercusliaotungensis-Q.spinosa,Pinusarmandii-Tiliapavcicostata,高杂灌;而在南向坡,依次为亚高山禾草——莎草科草甸—Salixpurpurea灌丛、Salixpurpurea—Artemigiatangutica、农耕地、裸岩一砾石坡。其总的演进趋向是:生境依次变干,植物量依次减少,土壤肥力依次降低,种的多样性经历着由“较单一到复杂再到单一”的贫化过程。Through investigating and researching the mixed decidious-coniferous forested e-cosystem,we found that the succession of the primary vegetation community of Pints tabulaeformis-Sinarundinaria nitida is turned into Betulaalbo-sinensis-S. nitida,B. Platyphylla-Populus davidiana,Quercus liaotungensis-Q.spinosa,P.armandii-Tilia paucicostata, the tall mixed brush on the north-facing slope and in-to subalpine grass-cyperaceae marshland ,Salix purpurea-mixed brush,tilledland ,bare gravel ground on the south-facing slope from high to low. On the basis of slopefacing and slope and altitude,underthe intensive influence of the livelihood activity of humanity,its evolution tends that the habitat be-comes arider and arider ,phytomass in fewer and fewer as well as the fertility of soil is lower and low-er in proper order. Diversity of the species in undergoing such a dilution course as “from simpler tocomplex and to the simplest”.
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