毛竹细根分布特征研究

为了解毛竹(Phyllostachys edulis)细根的分布规律,对不同水平距离和土层深度0~1 mm和1~2 mm细根的生物量、比根长、组织密度和根长密度进行了分析。结果表明,随着毛竹年龄的增加,细根生物量和根长密度先上升后降低,根组织密度先降低后升高,比根长呈降低的趋势。细根生物量和根长密度以距竹秆60 cm处最大,根组织密度以20 cm处最大,比根长在40 cm处最大,但他们在距竹秆不同距离间的差异不显著。细根生物量以10~20 cm土层最大,根组织密度以20~30 cm土层最大,细根生物量、比根长、组织密度和根长密度在不同土层间的差异不显著。与1~2 mm细根相比,0~1 mm细根生物量和根组织密度更小,比根长和根长密度更大。因此,毛竹年龄对细根生长具有显著的影响,1年生毛竹有最大的比根长和较大的根组织密度,具有更强的资源利用率。毛竹细根在一定的土层范围内呈均匀分布状态,可更有效地利用特定区域的水肥资源。

Fine Root Biomass Distribution of Moso Bamboo at Different Ages

The aim was to elucidate fine root biomass distribution differences of moso bamboo (Phyllostachys edulis) at different ages. The fine root biomass (W_FRB), specific root length (L_SRL), root tissue density (D_RTD), and root length density (D_RLD) were analyzed in the horizontal and vertical direction of different age moso bamboo. The results showed that along the age of moso bamboo, the W_FRB and D_RLD increased at first and then decreased, the L_SRL decreased, and the D_RTD decreased at first and then increased. The W_FRB and D_RLD were the biggest at 60 cm from main stem, the D_RTD and the L_SRL were at 20 cm and 40 cm, respectively. The differences of W_FRB, L_SRL, D_RTD and D_RLD were not significant among different horizontal distances from bamboo stem. The W_FRB was the biggest at 10-20 cm soil layer, and the D_RTD was at 20-30 cm soil layer. The differences of W_FRB, L_SRL, D_RTD and D_RLD were not significant among different soil depthes, too. The W_FRB and D_RTD of 0-1 mm fine roots were smaller than those of 1-2 mm fine roots, while the L_SRL and D_RLD were bigger. Therefore, the age of moso bamboo had significant effects on the growth of fine roots. The L_SRL and D_RTD of 1-year-old bamboo were bigger, which display greater resource utilization efficiency. The even distribution of fine roots of moso bamboo could more efficient use water and fertilizer resources in a particular area.