摘要
植被和土壤是消落带生态系统的重要组成部分.本研究选择三峡库区腹地忠县境内的3个地质地貌和土地利用历史相似的近自然消落带,对不同水位高程(160 m和170 m)植被群落和土壤特征进行研究,结果表明:一年生草本在消落带植物物种数中比例高达72.4%,而多年生草本仅为27.6%;不同水位高程植被物种组成完全相同,且盖度、生物量、生物多样性指数均没有显著差异;随着水位高程变化,群落优势物种存在一定差异,即160 m高程优势种为多年生狗牙根(Cynodon dactylon),而170 m高程为一年生白酒草(Conyza japonica);土壤容重、含水量、pH、有机质、总氮、总磷在160 m和170 m水位高程间均没有显著差异.因此,160 m和170 m水位高程在淹水时间和深度上的差异造成群落优势种的不同,而对当前植被和土壤特征并没有显著影响.
Vegetation and soil are the key components of the drawdown area of Three Gorges Reservoir.To investigate characteristics of vegetation and soil from water-level altitude of 160 m and 170 m,three drawdown areas with similar geological environment and history of land-use in Zhongxian County were chosen.Results indicated that percent of annual and perennial herbaceous species in drawdown area were 72.4% and 27.6%,respectively.There were no significant differences in species composition,coverage,biomass and biodiversity index between 160 m and 170 m.With water-level altitude changing,the dominant species of plant community varied.Cynodon dactylon was the dominant species at 160 m,while Conyza japonica at 170 m.Soil bulk density,water content,pH,SOM,TN and TP at 160 m and 170 m did not differ significantly.Therefore,it seems reasonable to suggest that their different dominant species resulted from the different inundation period and water depth in those areas between 160 m and 170 m,which did not play a significant role in current vegetation and soil development.
出处
《湖泊科学》
CAS
CSCD
北大核心
2012年第2期206-212,共7页
Journal of Lake Sciences
基金
国家水体污染控制与治理科技重大专项项目(2009ZX07104-003-01)资助
关键词
三峡库区
消落带
水位高程
植被
土壤
Reservoir limnology
spatial-temporal heterogeneity
long-term observation
phytoplankton blooms
hydrodynamic mechanism
forecasting model
eco-hydraulic regulation
Three Gorges Reservoir
