九洲江陆川县城区江段藻类群落调查

Investigation on Algae Community in Urban Area of Luchuan County;Jiuzhou River

在九洲江陆川县城区河段中选取6个采样点,于冬、春、夏、秋四个季度,对河段中浮游藻类和底栖硅藻进行了采样,分析其藻类群落结构及物种多样性,并利用香农-威纳指数、均匀度指数、丰富度指数等对水质进行生物学评价.结果显示:(1)底栖硅藻共30属88种,其中舟形藻属(Navicula) 13种,针杆藻属(Synedra) 11种,脆杆藻属(Fragilaria) 9种,羽纹藻属(Pinnularia) 9种;浮游藻类共8个门45个属75种,其中硅藻门(Bacillariophyta) 16属26种,种类分布最多,而蓝藻门(Cyanophyta) 12属22种,绿藻门(Chlorophyta) 10属19种,其余裸藻门(Euglenophyta)、隐藻门(Cryptophyta)、甲藻门(Dinophyta)、黄藻门(Xanthophyta)、金藻门(Chrysophyta)的种类都相对较少.(2)多样性指数变化范围在1～1.9之间,均匀度指数变化范围为0.243～0.608.(3)在季节变化上,物种均匀度指数、丰富度指数、多样性指数以降雨频繁的夏季最高.在水平分布上,距排污口距离越近,物种丰富度、多样性指数值越减小.(4)九洲江陆川县城区江段总体为中污水体,与实际观测的水体环境状况相吻合.

Six sampling sites were selected in the urban area of Luchuan County;Jiuzhou River. Phytoplankton andbenthic diatom were sampled in four seasons:winter;spring;summer and autumn. The community structure andspecies diversity of the algae were analyzed. The water quality was evaluated by Shannon-Weiner index;evennessindex and richness index. The results showed that:(1)There were 88 species of benthic diatoms belonging to 30 genera;including 13 species of Navicula;11 species of Synedra;9 species of Fragilaria and 9 species of Pinnularia;75 species of phytoplankton belonging to 45 genera and 8 phyla;of which 26 species belonged to 16 genera of Bacillariophyta;with the largest species distribution;while 22 species belonged to 12 genera of Cyanophyta and 22 species of green algae. There are 19 species belonging to 10 genera of Chlorophyta;and relatively few species of Euglenophyta;Cryptophyta;Dinophyta;Xanthophyta and Chrysophyta.(2)The diversity index ranged from 1 to 1.9;and the evenness index ranged from 0.234 to 0.608.(3)In terms of seasonal variation;species evenness index;richness index and diversity index are the highest in summer with frequent rainfall. On the horizontal distribution;the closer the distance from the sewage outlet is;the smaller the species richness and diversity index.(4)The urban section of Jiuzhou River;Luchuan County is generally a medium-sized sewage body;which is consistent withthe observed water environment.