密度结构对大青川红松人工林细根生物量与根长密度的影响  

Influence of Stand Density on Fine Root Standing Biomass and Length Density in Korean Pine(Pinus koraiensis)Plantation in Daqingchuan Forest Farm,Xiaoxing'an Mountain,China

作　　者：陈硕芃[1] 王韶仲[1] 王政权[1] 谷加存[1] 

机构地区：[1]东北林业大学林学院,哈尔滨150040

出　　处：《森林工程》2013年第4期1-7,共7页Forest Engineering

基　　金：国家科技支撑计划课题(2011BAD37B02-2);国家重点基础研究发展规划资助(2012CB416906)

摘　　要：在小兴安岭大青川林场,选择3种不同密度结构的红松人工林林分:低密度红松林(低红,处理A),高密度红松林(高红,处理B)和阔叶树占比例较大的红松林(高阔,处理C)。通过根钻法,研究不同直径等级红松根系生物量(SRD)和根长密度(RLD)及其在不同土壤深度的垂直分布特征,目的是揭示密度结构对红松根系,特别是吸收根的影响。结果表明:方差分析显示,林分密度结构、直径等级和土壤深度均是影响根系SRB和RLD的重要因子。密度结构仅对吸收根SB和RLD有稳定而显著的影响(P<0.05),处理B吸收根SRB和RLD均显著高于处理A和C;密度结构也显著改变了红松吸收根SRB和RLD的垂直分布比例(P<0.05),这表现为处理C中红松吸收根SRB在0～10 cm土层分配比例下降(处理A、B和C分别为65.9%、61.5%和49.8%),而在20～30 cm土层明显增加(处理A、B和C分别为13.7%、11.6%和23.8%)。这些结果表明,维持人工林中红松适宜的株数密度,并保留一定的阔叶树,能够同时促进红松个体胸径、树高和地下吸收根的充分生长,进而获得林分水平上较高的蓄积量和生物量生产。This study investigated the relationship between fine root standing biomass and length density and stand density in Korean pine（Pinus koraiensis）plantation,Daqingchuan forest farm,Xiaoxing＇an Mountain.Three stands with a gradient of density of Korean pine were selected,i.e.treatment A（lower portion of Korean pine）,treatment B（higher portion of Korean pine）and treatment C（higher portion of hardwoods）.Soil core method was used to determine how stand density affects the standing root biomass and root length density with diameter size classes,in particular of absorptive roots with diameter,as well as their vertical distribution.Our results showed that stand density,diameter size,and soil depth all have significant influence on SRB and RLD,however,consistent strong effect of stand density on SRB and RLD was only found in absorptive roots（diameter ≤0.5 mm）.Treatment B had significant higher SRB and RLD than treatment A and C.Stand density also changed the vertical distribution of SRB and RLD of absorptive roots.Treatment C had the lowest percentage of SRB of absorptive roots in 0-10 cm（49.8%）,but highest in 20-30 cm（23.8%）,in comparison with values of treatment A（65.9% and 13.7,respectively）and B（61.5% and 11.6%）.These findings suggest that a proper density and composition of Korean pine plantation could promote trees growth,and enhance absorptive roots development,as well as increase the stock and biomass at stand level.

关 键 词：吸收根 地下碳分配 近自然林 碳汇林 

分 类 号：S718[农业科学—林学]