摘要
以三种莎草科克隆植物藨草(Scirpus triqueter),海三棱藨草(Scirpus mariqueter)和糙叶苔草(Carex scabrifolia)为研究对象,通过盆栽受控实验,探讨三种初始种植密度处理(1株/盆、4株/盆和16株/盆)对个体表现与种群增长的影响。结果表明,三种植物种群经过一个月左右的适应后均开始加速增长,生长季后期增长率逐渐降低,而海三棱藨草种群甚至出现了一定程度的衰退。生长季中前期藨草在中低密度处理下密度增长率高于高密度和整簇种植处理,而海三棱蔗草、糙叶苔草种群的整体密度增长与初始种植密度成反比。最终收获时,藨草和海三棱蔗草不同处理下的密度、冠层高度、最高高度、地上生物量和地下生物量均没有显著差异,糙叶苔草在低种植密度下的密度最低,中等种植密度下冠层高度最高。薦草、海三棱藨草的单株平均生物量与密度呈显著负相关,而藨草、糙叶苔草的总生物量与密度呈显著正相关,三种莎草科植物的根冠比都没有随密度发生显著变化。三种莎草科植物在高密度下的种内竞争效应均强于中密度。
This study examined the effects of three initial planting density treatments（1,4 and 16 ramets per pot） on individual and population growth of Scirpus triqueter,Scirpus mariqueter and Carex scabrifolia using a controlled environment experiment.Our result showed that the population size of these three species increased rapidly after an adaptation period of about one month,the growth rate decreased gradually in late growing season and S.mariqueter even declined during this period.Density growth rate of S.triqueter in early growing season was higher in low and medium initial planting density treatments than that in high density and cluster planting treatments.Population growth of 5.mariqueter and C.scabrifolia had a negative correlation with initial planting density.At harvest,ramet density,canopy height,height of the tallest ramet,above- and belowground biomass of S.triqueter and S.mariqueter did not differ significantly among the three initial planting density treatments.However,for C.scabrifolia,the low initial density treatment had the lowest final density,while canopy height was the highest in the medium initial density treatment.Single ramet biomass of both S.triqueter and S.mariqueter had significantly negative correlations with their ramet density,while the total biomass of S.triqueter and C.scabrifolia was significantly and positively correlated with their ramet density.Root：shoot ratio of these species did not differ significantly with increasing ramet density at harvest,and they had more intense intraspecific competition in high density treatment than in medium density treatment.
出处
《生态科学》
CSCD
2016年第1期1-9,共9页
Ecological Science
基金
国家自然科学基金项目(31100317)
上海市科委科研计划项目(12231204703)
上海市科委科技创新行动计划(14DZ1206003)
关键词
种群增长
密度效应
藨草
海三棱藨草
糙叶苔草
population growth
density effect
Scirpus mariqueter
Scirpus triqueter
Carex scabrifolia
