九寨沟风景区秋季水体硅藻的海拔梯度变化  

Autumn Diatom Variation in Lakes Along Altitude Gradient in the Jiuzhaigou National Park,Sichuan,China

作　　者：周晓[1,2] 高信芬[1] 羊向东[3] 李艳玲[3] 

机构地区：[1]中国科学院成都生物研究所,成都610041 [2]中国科学院研究生院,北京100049 [3]中国科学院南京湖泊与地理研究所,南京210008

出　　处：《应用与环境生物学报》2009年第2期161-168,共8页Chinese Journal of Applied and Environmental Biology

基　　金：国家“十一五”科技支撑计划重大项目(No.2006BAC01A15)资助~~

摘　　要：九寨沟是著名的世界自然遗产地,水是九寨沟自然风景的灵魂,因而关于九寨沟湿地的研究极为重要.硅藻的生长和繁殖对环境极为敏感,长期作为湿地水质监测的指标.对四川九寨沟风景区内17处采样点水体中的硅藻进行了实地调查研究,经鉴定共发现113个分类单位,包括种和变种,隶属于2纲6目10科32属.脆杆藻属、舟形藻属、桥弯藻属和异极藻属常为优势属,只在长海是以小环藻属为单一优势属的群落.首次发现典型的富营养化指示种颗粒直链藻[Melosira granulata(Ehr.)Ralfs]和星形冠盘藻[Stephanodiscus astraea(Ehr.)Grun.]在旅游旺季出现,并在淡季消失,表明旅游对九寨沟核心景区的湖泊产生了一定的影响,而其生态系统具有较强的自我调节功能.数量统计和相关分析结果表明,硅藻细胞密度受到环境因子的综合作用而表现出与海拔显著的正相关;反映多样性的Cairns连续比较指数(SCI)普遍较高(长海除外),与海拔显著负相关,与密度极显著负相关,可以都从种间竞争得到解释;SCI不一定反映了水体水质.The Jiuzhaigou National Park in Sichuan, China is also a famous world natural heritage site. The water is the soul of the National Park and the wetland consists of 118 mountain lakes. In order to evaluate the status of the wetland, and to put forward rational advices for the wetland protection, a series of studies on the wetland were conducted. Diatom was used to monitor water quality because of its great sensitiveness to environmental changes. Based on the studies of 17 sampling sites in lakes from 2 168 m to 3 060 m in a gradient altitude in October - December 2007, 113 taxa of diatoms （including species and varieties） were observed. The predominant genera in most sampling sites were Fragilaria, Navicula, Cymbella and Gomphonema, but the dominant Cyclotella only in the Long Lake. Two eutrophication-indicating species, Melosira granulata （Ehr.） Ralfs and Stephanodiscus astraea （Ehr.） Grun., were found for the first time in the lakes of Jiuzhaigou in traveling season, and they disappeared in winter, indicating that human activities had impact on the lakes of Jiuzhaigou, and the ecological system had a strong ability to be recovered by itself. The result of statistical analysis showed that diatom cell density and altitude represented a positive relation as a result of co-effect of environmental factors. The Cairns Sequential Comparison Index （SCI）, a simplified method to estimate the relative differences in biological diversity, was high except for the Long Lake, and it had negative relation with altitude and cell density, both resulted from interspecies-competition. But the SCI could not always reflect the quality of the lake water in Jiuzhaigou. Fig 2, Tab 6, Ref 25

关 键 词：九寨沟 硅藻 细胞密度 生物多样性 Cairns连续比较指数 

分 类 号：Q948[生物学—植物学]