岷江上游半干旱河谷灌丛的主要类型

MAIN TYPES OF THE SEMI-VALLEY SCRUBS IN THE UPPER REACHES OF THE MINJIANG RIVER

岷江上游半干旱河谷灌丛不连续分布于岷江河面以上３００－１００ｍ处。从群落学角度对这种灌丛研究的结果表明：区内植物生活型谱主次为高位芽植物＞地面芽植物＞地下芽植物＞一年生植物＞地上芽植物。岷江上游半干旱河谷灌丛分为２个群系组，７个群系和１０个群丛，并对主要群系的分布及特点进行了分析。

The semi-arid valley scrubs in the upper reaches(31°15′ 32°32′N,103°10′ 103°54′E)ofthe Minjiang River distribute discontinuosly along the river banks and Occupy a300 400m widebeIt on the slopes.This special vegetation is researched systematically in view of communitybiology,distribution and characteristics of communities. The studied results of the lifeformspectrum show that Ph>H>G>Th>Ch , which reflect that there iS a warm,rainy summer anda long winter.The scruds may be classified into 2 formation groups,7 formations and 10associations,which can be integrated as follows:Form. 1 Campylotropis wilsonii+Indigofera lenticellata+AjaniaForm. 2 Bauhinia Faberi var microphylla+Ceratostigma minus+Indigofera lenticellata+Ajania potaniniiForm. 3 Bauhinia faberi var.microphylla+Sophora viciifolia+Ceratostigma minus+INdigofera lenticellata+Ajania potaniniiPorm. 4 Indigofera lenticellata+Ceratostigma minus+Ajania potaniniiForm. 5 Convolvulus tragacanthoidesForm. 6 Caragana tibeticaForm. 7 Cotoneaster gracilis+Caragana boisi+Amygdalus tangutica+Berberis SP.Among these formations Form. 1,3 are most widely distributed, while Form. 5 manifests asemi-desert landscape.