摘要
为了解影响热带天然次生林稀疏的因素,本研究应用地上生物量模型、多样性指数和O-ring统计对固定样地中植物的地上生物量、物种多样性和空间分布格局进行定量研究,并结合Yoda自疏模型计算林分稀疏指数,分析物种多样性与空间格局对林分稀疏的影响。结果表明:林分地上生物量随着林分密度的减小呈现先增大,后减小,再增大的趋势,在径级Ⅲ或径级Ⅳ处,出现变化拐点,在天然林管理时应加以注意。多样性指数与林分稀疏指数总体上无显著的相关性,但中等多样性指数值却对应最大的稀疏指数。说明物种多样性中等情况下,林分稀疏最为强烈。植物个体聚集分布的最大强度与稀疏指数呈显著线性负相关,二者的回归方程为:α=-1.7873O11(r)max+2.3451(R2=0.798,P=0.003)。结果表明,在热带常绿季雨矮林中,过大的聚集强度不但不能促进稀疏过程的进行,反而会对其产生阻碍作用。
In order to understand the factors influencing stand thinning in tropical natural second-ary forests, aboveground biomass, species diversity and spatial patterns were quantitatively ana-lyzed by using aboveground biomass model, diversity index and 0-ring statistics. Moreover, theeffects of species diversity and spatial patterns on stand thinning were studied with thinning indexcalculated by Yoda self-thinning model. The results showed that stand aboveground biomass in-creased first, then decreased and increased finally with declining stand density. An inflectionpoint of aboveground biomass change occurred at diameter class m or IV, and this should bepaid attention to during forest management. In general, there was no significant correlation be-tween diversity index and stand thinning index. However, the medium value of species diversityindex corresponded to the largest thinning index, suggesting that stand thinning was strongest withthe medium species diversity. A significant negative linear correlation existed between largest ag-gregation intensity and thinning index as follows ： a = - 1.7873 O 11 （r） ＋ 2. 3451 （ R2 = 0. 798,P = 0.003）. The results indicated that if plant population assembled excessively, stand thinningwould be suppressed rather than promoted in the tropical evergreen monsoon elfin forest.
出处
《生态学杂志》
CAS
CSCD
北大核心
2015年第2期571-581,共11页
Chinese Journal of Ecology
基金
国家自然科学基金项目(31060073)
国家重点基础研究计划前期项目(2010CB134512)
中医药行业科研专项海南省代表性区域中药资源保护利用项目(201207002-03)资助
关键词
林分稀疏
地上生物量
物种多样性
空间分布格局
热带常绿季雨矮林
stand thinning
aboveground biomass
tern
tropical evergreen monsoon elfin forest.species diversity
spatial distribution pat-
