摘要
香溪河系长江三峡水库湖北库区内第一大支流.对香溪河2005年7月—2006年6月干流及主要支流上12个样点的附石藻类进行调查,共观察到藻类218种,其中硅藻183种、绿藻24种、蓝藻10种、黄藻1种,硅藻门的线形曲壳藻为绝对优势种.其物种丰富度和Shannon-Wiener多样性指数时空动态差异显著(或接近显著),总平均值分别为32和1.54.附石藻类密度和叶绿素a含量年总平均值分别为8.75×109cells.m-2和14.62 mg.m-2.不同样点的藻类密度和叶绿素a含量差异显著,其中古夫河支流最高,九冲河支流最低,两者相差一个数量级;不同季节附石藻类密度和叶绿素a含量差异不显著(P>0.05),但均表现出冬春季高、夏秋季低的趋势.附石藻类密度及叶绿素a含量与海拔及水流流速呈显著负相关,而与总氮呈正相关.
Xiangxi River system is the greatest branch in the Hubei reservoir area of the Three Gorges reservoir. In this paper, the epilithic algae in the River and its three major tributaries were investigated from July 2005 to June 2006. A total of 218 taxa were identified, including 183 species of Bacillariophyta, 24 species of Chlorophyta, 10 species of Cyanophyta, and one species of Xanthophyta. The diatom Achnanthes linearis was the most predominant species. The richness and Shannon-Wiener diversity indices varied significantly （or almost significantly） over time and space, and the total average values were 32 and 1.54, respectively. The total averages of annual epilithic algal density and chlorophyll a concentration were 8.75×10^9 cells·m^-2 and 14. 62 mg·m^-2, respectively. There were significant differences in the algal density and chlorophyll a concentration among different sampling sites, and the maximum values were observed in Gufu River tributary, which were one order of magnitude higher than the minimum ones in Jiuchong River tributary. The algal density and chlorophyll a concentration tended to be higher in winter and spring than in summer and autumn, but no significant differences were observed in various seasons. Epilithic algal density and chlorophyll a concentration were significantly negatively correlated with elevation and water current, but positively correlated with the total nitrogen concentration in water.
出处
《应用生态学报》
CAS
CSCD
北大核心
2008年第4期881-886,共6页
Chinese Journal of Applied Ecology
基金
国家自然科学基金重点项目(30330140)
国家重点基础研究发展规划项目(2002CB412300)
中国科学院知识创新工程重要方向资助项目(KZCX2-YW-427,KSCX2-SW-111)
关键词
附石藻类
时间动态
空间格局
香溪河
epilithic algae
temporal variation
spatial pattern
Xiangxi River.
