徐州石灰岩山地侧柏人工林生物量及其影响因子分析

Biomass and its influencing factors of Platyclatdus orientalis plantation in the limestone mountains of Xuzhou

生物量和生产力是评估森林生态服务功能的重要指标,也是人工林可持续经营的科学依据。对徐州石灰岩山地50年生的侧柏纯林生物量及其影响因子研究,结果如下:(1)单株侧柏的生物量为8.88～80.71 kg,各个器官生物量比例总体呈树干>树枝>树根>树叶或树干>树枝>树叶>树根的顺序;(2)侧柏各测树因子中,关系最密切的是地上生物量与单株总生物量,其次是树干生物量与地上生物量,各部分干重与胸径及D2H之间存在着紧密的相关性,与树高的相关性较弱;(3)8块侧柏人工林生物量的变动范围为28.92～75.42 t.hm-2,平均值为54.35 t.hm-2;(4)朝北指数与林分生物量显著相关,其他因子同林分生物量没有明显的相关关系;林分密度与林分生物量、林分密度与地上生物量都呈现出单峰曲线关系。当林分密度为2 600株.hm-2左右时,林分生物量和林分地上生物量数值接近最大。

Biomass and productivity are critical parameters for assessing forest carbon sequestration capability and the quantitative estimates are required for forest biomass carbon accounting.We studied the 50-year-old Platyclatdus orientalis plantations in the limestone mountains of Xuzhou,and the results showed that：（1） Whole-tree was in a range of 8.88-80.71 kg.Allocation of biomass to organs followed a sequence of trunk〉branch〉root〉leaves or trunk〉branch〉leaves〉root;（2） Significant correlation was found between the whole tree biomass and aboveground biomass,followed by trunks and aboveground biomass.Correlation between organ biomass and tree height was lower than that with diameter at breast height and D2H;（3）Biomass for stands of 8 plots was in the range of 28.92-75.42 t·hm-2,with the average value of 54.35 t·hm-2;（4） Biomass for stands were positively correlated with the north aspect index,while other factors took no effect on it.The response curves of biomass or aboveground biomass to stand density were both unimodal.Biomass and aboveground biomass had the maximum values when stand density was closed to 2600 trees·hm-2.