施肥梯度对甘南高寒草甸植被特征的影响

通过小区控制施肥实验,研究了施肥梯度对青藏高原东缘高寒草甸植被特征的影响.结果表明,1) 施肥使线叶嵩草、波伐早熟禾、垂穗鹅观草等禾草的高度显著增加,异针茅、瑞玲草等非禾草类的高度减少.2) 随着施肥梯度的增大,群落的总密度逐渐下降, 禾草密度在不同施肥梯度下有时增加,有时减少,无一般性规律;而非禾草物种密度一般是减少的.3) 随施肥梯度的增加,地上生物量明显提高,多样性指数逐渐下降.施肥对群落密度、地上生物量和多样性的作用都要在2年以后才表现出明显的规律.

The effect of fertilizer gradients on vegetation characteristics in alpine meadow

The effect of fertilizer gradients on vegetation character in alpine meadow was studied by fertilizing experiment. The results showed :1) Height of the herbage such as Kobresia capillifolia,Poa poophagorum,Roegneria nutans, et al.increased significantly along the fertilizer gradient,but the height of Stipa aliena and Saussurea nigrescens decreased significantly. 2) Community density decreased along the fertilizer gradient. Changes of the herbage density were different along the fertilizer gradient; other plant populations density commonly decreased. 3) Plant aboveground biomass increased significantly,but species diversity decreased along fertilizing gradient. Effect of the fertilizing on community density,productivity and species diversity represented distinctly only after two years.