干旱河谷草本植物随海拔变化的物种多样性

为研究白龙江干旱河谷区域不同坡向草本群落沿着海拔梯度物种多样性的变化,利用样方法对该区进行了研究。结果表明:在调查区域内,草本植物共21科37属42种,其中菊科植物10种,占所有草本植物种数的23.81%,禾本科植物9种,占所有草本植物种数的21.42%;不同坡向草本群落α多样性指数随着海拔的升高,表现出先升高后降低的趋势。阳坡草本群落在海拔1 250 m时,α多样性指数达到最大值,阴坡植物在海拔1 450 m出现最大值,半阴半阳坡草本群落在海拔1 450 m出现最大值;不同坡向均匀度指数(R)随着海拔梯度的升高变化较小;β多样性指数随着海拔的升高变化较大,阳坡植物的β多样性指数在海拔1 051~1 250 m时达到最大,阴坡和半阴半阳坡在海拔1 251~1 450 m时达到最大,半阴半阳坡的β多样性指数均大于阳坡。

Biodiversity of herbaceous plants along altitude gradient in the arid valley

This paper studied the variation of the species diversity of herbaceous community along the altitude gradient in the arid valley of the Bailong River. The results showed that:in the survey area, there were a total of 42 herbaceous species, belonging to 21 families, 37 genera, among which there were 10 species of Asteraceae, accounting for 23.81% of total herbaceous species, 9 species of Gramineae, accounting for 21.42%. The diversity of the herbaceous community in different slope aspects increased firstly and then decreased with the growing of altitude. Theαdiversity index of the grass community reached the maximum at the altitude of 1250 m in sunny slope, at the altitude of 1450 m in shady slope and semi-shady-sunny slope. The evenness index slightly changed in different slope with the increase of the elevation. βdiversity index of plant community greatly varied with altitude addition, reaching the maximum in the altitude of 1051 m to 1250 m in shady slope and at the altitude of 1251 m to 1450 m in semi-shady and semi-sunny slope and the β diversity index in semi-shady and semi-sunny slope was higher than that of sunny slope.