水位调节对三峡水库消落带植被群落特征的影响  

Effect of water level regulation on vegetation characteristics in the water-level-fluctuation zone of the Three Gorges Reservoir

作　　者：由永飞[1,2] 杨春华 雷波[1] 张晟[1] 王业春[1] 刘建辉[1] 

机构地区：[1]重庆市环境科学研究院,重庆401147 [2]重庆环投生态环境监测网络与工程治理有限公司,重庆401147

出　　处：《应用与环境生物学报》2017年第6期1103-1109,共7页Chinese Journal of Applied and Environmental Biology

基　　金：水体污染与控制国家科技重大专项(2012ZX07104-003);重庆市自然科学基金计划重点项目(cstc2012jj B20003);重庆市基本科研业务费计划项目(2016-hky-jcyj-01702)资助~~

摘　　要：水位运行或调节模式是影响水库消落带植被组成与结构的关键因素,三峡水库独特的水位调节形成了具有明显不同出露-淹没特征的梯度性消落带.为了解水位调节对三峡库区消落带植物群落特征的影响,选择在三峡水库高水位运行5年后,在库区腹地3个受人为干扰较小且近自然状态的消落带,开展了不同高程(150 m、160 m和170 m)梯度的消落带植被物种组成、盖度、生物量、生物多样性和优势物种的比较研究.结果显示:消落带植被共有51种植物,多年生和一年生植物分别为25种和26种;随着高程增加,总物种数量越来越高,3个高程分别为8种、22种和45种分布;150 m高程盖度和生物量明显低于160 m和170 m两个高程,而后两者均没有显著差异;不同水位高程优势种明显不同,以白酒草为主的一年生植物多分布在消落带170 m高程,以狗牙根和马唐为主的多年生和一年生植物分布在消落带的160 m高程,以狗牙根为主的多年生植物分布在150 m高程;生物多样性指数随着高程的增加而变大,其中Shannon-Wiener多样性指数在150 m、160 m和170 m高程分别为0.877±0.298、2.137±0.186和3.097±0.407.综上表明,水位调节导致三峡水库消落带植被在30 m高程(145-175 m)范围内形成了不同组成与结构的群落,优势物种间差异可能是消落带植物对三峡水库水位调节模式的一种适应性策略体现;150 m高程出露时间相对较短,其土壤沉积物淤积严重,表层土壤种子库萌发受影响,物种数量、生物多样性、植被盖度和生物量明显低于其他高程,自然恢复能力较差.Annual water level regulation of reservoirs is a key factor affecting plant community and structure in the water-level-fluctuation zone （WLFZ）. The unique water level regulation of the Three Gorges Reservoir （TGR） in China has formed a gradient WLFZ with distinct exposed-inundated characteristics. The aim of this study was to investigate the effect of water level regulation on the vegetation community characteristics in the WLFZ of the TGR. After a 5-year high water level running of the TGR, three experimental plots comprising nearly natural areas with minimal human disturbance in the WLFZ in the heartland of the TGR were selected. The vegetation species composition, coverage, biomass, biodiversity, and dominant species at different elevation zones （150 m, 160 m, and 170 m） were studied. Perennial and annual plants accounted for 49.02% （25/51） and 50.98% （26/51）, respectively, of the plants identified. The number of species increased at higher elevations. At elevations of 150 m, 160 m, and 170 m, there were 8, 22, and 45 species, respectively. The vegetation coverage and biomass were significantly lower at 150 m than at 160 m and 170 m, and they did not differ significantly between 160 m and 170 m. The dominant species at different elevations differed markedly; annual plants represented by Conyza japonica were distributed at 170 m, perennial and annual plants represented by Cynodon dactylon and Digitaria sanguinalis were distributed at 160 m, and perennial plants represented by C. dactylon were distributed at 150 m. The diversity index increased at higher elevations. At 150 m, 160 m, and 170 m, the Shannon-Wiener diversity index values were 0.877 ± 0.298, 2.137 ± 0.186, and 3.097 ± 0.407 respectively. Owing to water level regulation, the WLFZ vegetation community and structure differed significantly across 30 m （145–175 m）. The variation in dominant species at different elevations is likely an adaptive strategy for water level regulation in the TGR. Owing to the relatively short expos

关 键 词：三峡水库 水位调节 高程 消落带 植被群落特征 

分 类 号：Q948[生物学—植物学]