【摘要】 采用连续钻取土芯法在生长季内对东北林业大学帽儿山实验林场17年生水曲柳人工林根系取样,研究水曲柳不同直径根系现存生物量、比根长和根长密度及垂直分布状况.结果表明,水曲柳人工林根系总生物量为1 637.6 g.m-2,其中活根生物量占85%,死根占15%.在活根生物量当中,粗根(直径5~30mm)占的比例最高(69.95%),其次为活细根(直径<1 mm,13.53%),小根(1~2 mm)和中等直径的根(2~5 mm)比例较小(分别为7.21%和9.31%).直径<1 mm活细根的比根长为32.20 m.g-1,直径5~30mm粗根的比根长为0.08 m.g-1.单位面积上活根的总长度为6 602.54 m.m-2,其中直径<1 mm的细根占92.43%,其它直径等级则不到活根总长度的8%.直径<1 mm的细根生物量与根长密度具显著线性关系(R2=0.923),但与比根长无显著相关关系(R2=0.134).更多还原

【Abstract】 Employing soil core method,an investigation in Maoershan Experiment Station was made on the root biomass,specific root length（SRL）,and root length density （RLD） of Fraxinus mandshurica plantation（17 yr） within a growth season in stand level.The results showed that the total root biomass was 1 637 g·m^-2,in which,living biomass accounted for 85%,and necrotic biomass was 15%.In the living biomass,coarse roots（5～30 mm in diameter） had the highest percentage（69.95%）,followed by fine roots（<1 mm in diameter）（13.53%）,medium roots（2～5 mm in diameter）（7.21%）,and small roots（1～2 mm in diameter）（9.31%）.Among the four diameter classes,fine roots had a higher SRL(32.20 m·g^-1),while coarse roots had a lower one(0.08 m·g^-1).The total RLD in living biomass was 6 602.54 m·m^-2 in stand level,among which,fine root accounted for 92.43%,and the others was less than 8%.Fine root biomass and RLD had a positive correlation with soil available nitrogen,while no significant correlation was found between SRL and soil available nitrogen.更多还原