云雾山本氏针茅群落根系分布特征

Distribution Characteristics of the Root System of the Stipa bungeana Trin. Community in Yunwu Mountain

为揭示本氏针茅（Stipa bungeana Trin.）群落的生理生态适应机制，采用根系取样器（Φ=9 cm）对宁夏云雾山本氏针茅群落根系分布特征和土壤含水量进行研究。结果表明：本氏针茅群落地下生物量、根长密度、根表面积、比根长均随土壤深度增加而减少，均表现出向表层（0-20 cm）集聚的趋势，且集中分布于0-40 cm土层，最大值均分布在0-20 cm土层，而底层（80-100 cm）最小；所有主要根系分布参数在0-20 cm和20-40 cm土层之间差异显著，以下各层差异不显著；土壤含水量与根生物量和比根长相关性达显著水平（P〈0.05），与根表面积、根长密度均呈成正相关；根表面积、根生物量、根长密度和比根长间相关性均达极显著水平（P〈0.01）。

In order to reveal the physiological adaptation mechanism of the Stipa bungeana Trin. community in Yunwu mountain, soil auger was applied to investigate the distribution characteristics of the root system and the soil water content of the S. bungeana community in Yunwu mountain in Ningxia. The results show that the root biomass, root length density, root surface area, and specific root length decreased with the increasing of soil depth and greatly concentrated in the 0-20 cm with major distribution in the 0-40 cm soil layer, while little was distributed in deeper soil. The values of the above root parameters peaked in the uppermost （0-20 cm） soil layer while the minimum were observed in 80-100 cm soil layer. All of the main root parameters were different significantly between 0-20 cm soil layer and 20-40 cm soil layer, while no significant difference for the deeper soil layers. The soil water content was significantly correlated to the root biomass and specific root length at the 0.05 level and positively correlated to the root Surface area and root length density. The correlations among the root parameters of the S. bungeana community were very significant at the 0.01 level.