摘要
通过野外调查与室内实验相结合的方法,以晋西黄土区不同林分密度的油松人工林为对象,以林下植物多样性、枯落物蓄水、土壤物理性质和土壤蓄水能力为指标,分析了不同密度油松林对这些指标的影响,以期为油松林合理密度的确定提供科学依据。结果表明:油松林内灌木层物种丰富度指数、多样性指数随油松林密度的增大而减小,而均匀度指数无明显规律;草本层物种丰富度指数与灌木层变化规律一致,但多样性指数和均匀度指数均先增后减;油松林密度为1675株·hm-2时草本的多样性和均匀度为最大,整个群落的多样性指数和均匀度指数也最大;油松林灌木层的多样性指数及均匀度指数均大于草本层;不同密度油松林枯落物自然含水率无显著差异,而枯落物蓄积量、最大持水率以及持水量、有效拦蓄率和拦蓄量在一些林分密度间差异显著;密度为1300株·hm-2时,土壤容重最小,总孔隙度、毛管孔隙度及所对应的贮水量均最大;密度为1675株·hm-2时枯落物蓄积量、持水量最大,表层(0～20cm)土壤容重(1.07g·cm-3)相对较低,非毛管孔隙度(17.45%)及滞留贮水量(87.25mm)最大。综合来看,30年生左右的油松人工林,当密度约为1675株·hm-2时林下植物多样性及生态水文效应最好。
Taking the Pinus tabulaeformis plantations with different stand densities in the Loess Plateau of Western Shanxi Province, China as the objects, and by the methods of field survey and laboratory experiment, this paper studied the effects of stand density on the understory plant spe- cies diversity, litter water-holding capacity, soil physical properties, and soil water-holding ca- pacity, aimed to provide scientific basis for the determination of reasonable stand density of P. tabulaeformis plantation. With the increasing P. tabulaeformis stand density, the understory spe- cies richness index and diversity index of shrub layer decreased, while the species evenness index had no obvious trend. In herb layer, the species richness had the same variation trend as that in shrub layer, while the diversity index and evenness index had different trend, i. e. , decreased after an initial increase, and reached the maximum when the P. tabulaeformis stand density was 1675 trees · hm-2. The species diversity index and evenness index of the total community were also the highest at the stand density 1675 trees · hm-2. Both the evenness index and the diversity index of the shrub layer were higher than those of the herb layer, no matter the stand density was. The litter natural water content in P. tabulaeformis plantations with different stand densitieshad no significant difference, but the litter amount, maximal water-holding capacity, maximal water-holding rate, effective interception amount, and effective interception rate had significant differences among some plantations with different stand densities. When the stand density was 1300 trees · hm-2, the soil bulk density was the minimum, while the total porosity, capillary po- rosity, and their corresponding water-holding capacity all reached the maximum. At the stand density 1675 trees · hm-2 , the litter amount and water-holding capacity were up to the maximum values, the surface （0-20 cm） soil bulk density was lower （1.07 g · cm-3）, and the non-capil- lary porosity and non-capillary water-holding capacity were the largest （ 17.45% and 87.25 mm, respectively）. Overall, the P. tabulaeformis plantation of about 30 years old had the greatest un- derstory plant species diversity and the best eco-hydrological effect when the stand density was 1675 trees · hm-2.
出处
《生态学杂志》
CAS
CSCD
北大核心
2013年第5期1083-1090,共8页
Chinese Journal of Ecology
基金
"十二五"国家科技支撑项目(2011BAD38B0603)资助
关键词
油松人工林
林分密度
植物多样性
水文效应
Pinus tabulaeformis plantation
stand density
plant species diversity
hydrologicaleffect.
作者简介
作者简介李民义，男，1983年生，硕士研究生，主要研究方向为水土保持与植被恢复。E-mail：li_min_yi@163．com
通讯作者E-mal：zhangiianjun@bjfu.edu．cn
