栓皮栎地上部分构型及生物量分配

Aboveground architecture and biomass distribution of Quercus variabilis

研究秦岭南坡商洛地区不同径级栓皮栎的地上部分构型、生物量及其分配和构型与生物量的关系.结果表明：不同径级栓皮栎地上部分构型与生物量的分配存在差异.随着径级的增大,栓皮栎树高、胸径和冠幅逐渐增大;平均递减率先增大后减小;栓皮栎总体分枝率和逐步分枝率先增加后下降;不同径级栓皮栎垂直方向上的比叶面积为0.02-0.03,叶重比、叶面积指数和叶面积比的较大值在径级为Ⅰ、Ⅱ、Ⅲ时出现于树干中、上部,在径级为Ⅳ、Ⅴ、Ⅵ时出现在树干中部,径级进一步增大则在垂直方向上出现2个峰值,分别位于树干中下部和中上部.栓皮栎地上部分生物量中,树干生物量占71.8%-88.4%,枝生物量占5.8%-19.6%,叶生物量占4.2%-8.6%.随着径级的增大,树干生物量所占比例先减小后增大,而枝、叶生物量所占比例呈先增大后减小再增大的趋势.栓皮栎地上部分生物量与树高、胸径、冠幅和逐步分枝率（R2∶1）呈显著正相关,与总体分枝率和逐步分枝率（R3∶2）呈正相关趋势,但相关性不显著.树干生物量、地上总生物量与树干递减率呈负相关趋势,枝生物量、叶生物量与树干递减率呈正相关趋势,但相关性均不显著.

The aboveground architecture,biomass and its allocation,and the relationship between architecture and biomass of Quercus variabilis of different diameter classes in Shangluo,south slope of Qinling Mountains were researched. The results showed that differences existed in the aboveground architecture and biomass allocation of Q. variabilis of different diameter classes. With the increase of diameter class,tree height,DBH,and crown width increased gradually. The average decline rate of each diameter class increased firstly then decreased. Q. variabilis overall bifurcation ratio and stepwise bifurcation ratio increased then declined. The specific leaf areas of Q.variabilis of all different diameter classes at vertical direction were 0. 02- 0. 03,and the larger values of leaf mass ratio,LAI and leaf area ratio at vertical direction in diameter level Ⅰ,Ⅱ,Ⅲ appeared in the middle and upper trunk,while in diameter level Ⅳ,Ⅴ,Ⅵ,they appeared in the central trunk,with the increase of diameter class,there appeared two peaks in vertical direction,which located in the lower and upper trunk. The trunk biomass accounted for 71. 8%- 88. 4% of Q. variabilis aboveground biomass,while the branch biomass accounted for 5. 8%- 19. 6%,and the leaf biomass accounted for 4. 2%- 8. 6%. With the increase of diameter class,stem biomass proportion of Q. variabilis decreased firstly then increased,while the branch and leaf biomass proportion showed a trend that increased at first then decreased,and then increased again. The aboveground biomass of Q. variabilis was significantly positively correlated to tree height,DBH,crown width and stepwise bifurcation ratio（ R2： 1）,and positively related to the overall bifurcation ratio and stepwise bifurcation ratio（ R3： 2）,but there was no significant correlation. Trunk biomass and total biomass aboveground were negatively related to the trunk decline rate,while branch biomass and leaf biomass were positively related to trunk decline rate,but their correlations were all not significant.