林秀华

摘 要：以32年生杉木大径材林分为研究对象，分析20cm、25cm、30cm 3个不同胸径杉木单株不同径级根生物量及其垂直空间分布特征。结果表明，随着杉木胸径的增长，杉木单株根系总生物量呈逐渐增大的趋势；杉木粗根总生物量表现为胸径30cm>25cm>20cm，杉木大根总生物量表现为胸径20cm>30cm>25cm，杉木中根总生物量表现为胸径25cm>20cm>30cm，小根及细根总生物量均表现为30cm>20cm>25cm；随着土层深度增加，杉木粗根、大根总体上表现为随着杉木胸径的增大其根生物量也呈逐渐增加的趋势，杉木中根在深层土层表现为随着杉木胸径增大其生物量呈现先上升后降低的趋势，杉木小根及细根总体表现为随着胸径增大其生物量呈先降低后上升的趋势。

关键词：杉木；胸径；根；生物量；垂直分布特征

中图分类号 S79 文献标识码 A 文章编号 1007-7731（2018）12-0085-4

The Vertical Spatial Pattern of Root Biomass of Different Diameters Tree in Chinese-fir Big-diameter Forest

Lin Xiuhua

（National Forest Farm of Youxi County，Youxi 365100，China）

Abstract：Taking 32 year old Chinese fir plantation as the research object， the root biomass and its vertical spatial distribution characteristics of 3 different diameter Chinese fir with different diameter at 20cm， 25cm and 30cm were analyzed. The results showed that the total biomass of root system increased gradually with the increase of DBH. The total biomass of Chinese fir was 30cm>25cm>20cm， and the total biomass of Chinese fir one was 20cm>30cm>25cm. The total biomass of Chinese fir was 25cm>20cm>30cm， and the total biomass of small root and fine root was 30cm>20cm>25cm. With the increasing of soil depth， the root biomass of Chinese fir gradually increased with the increasing of the breast diameter of Chinese fir. The growth of Chinese fir root in the deep layer showed a tendency to increase and then decrease with the increasing of the breast diameter of Chinese fir， and the small root and fine root of Chinese fir increased with the increasing of the diameter of the chest. The biomass of the large scale decreased first and then increased.

Key words：Chinese fir；Diameter；Root；Biomass；Vertical spatial pattern

根是林木最重要的營养器官之一，它不仅起到固土护土及机械支撑树体的功能，而且也是植株吸收土壤水分、养分及同化物分配的重要器官，根系生长过程中各种生理活动及死亡后的腐解过程均会与土壤进行物质交换与能量流动，根系生长的好与坏直接影响着林木的生长[1]。根系生物量不仅与树种的生物学特性有关，而且还与土壤温度及土壤肥力有直接的关系[2]。由于林木根较深，根系较庞大，根系研究工作量较大，林木地上部分的研究多于林木地下部分的研究[3-7]。

杉木是我国南方最重要的速生用材树种之一。在全国各用材林树种中，杉木人工林的面积、蓄积量和林业产值均居我国主要造林树种的前茅。长期以来，木材市……