广州市典型中小型水库营养状态与蓝藻种群特征

Nutritional status and population characteristics of Cyanobacteria in small and medium sized reservoirs in Guangzhou,southern China

中小型水库是广州市供水的重要水源地和后备水源地,为了解这类水库的富营养化特征以及蓝藻种群的动态,于2010年的枯水期、丰水期对广州市6座典型的中小型水库进行了采样与分析。结果表明：梅州水库、芙蓉嶂水库为贫-中营养型,三坑水库、百花林水库、和龙水库为中-富营养型,洪秀全水库为富营养型,水库营养状态指数季节变化差异不显著。在同一座水库中,水力滞留时间越长,营养状态指数越高;在不同水库之间,营养状态指数与集雨区内人类活动影响有关。6座水库蓝藻生物量的季节变化明显,受水温和水体稳定性的影响,枯水期蓝藻生物量在0.14~171.8μg.L-1之间,占浮游植物总生物量的0.1%~10.0%;丰水期蓝藻生物量在0.013~32.8 mg.L-1之间,占浮游植物总生物量的6.5%~97.0%。不同营养状态的水库之间蓝藻的生物量和种类差异明显,受营养盐和水力滞留时间的影响,梅州水库、芙蓉嶂水库蓝藻生物量在0.1~16μg.L-1之间,主要种类为泽丝藻（Limnothrix redekei）、卷曲鱼腥藻（Anabaena pertuthate）、水华微囊藻（Microcystis flos-aquae）、粘球藻（Gloeocapsa sp.）;三坑水库、百花林水库、和龙水库蓝藻生物量在0.057~32.8 mg.L-1之间,主要优势种为拟柱孢藻（Cylindrospermopsis raciborskii）、泽丝藻、假鱼腥藻（Pseudanabaena limnetica）;洪秀全水库蓝藻生物量在0.107~2.637 mg.L-1之间,主要优势种为阿氏颤藻（Oscillatoria agardhii）、水华微囊藻、卷曲鱼腥藻。

The small and medium sized reservoirs are important sources or backup sources for water supply in Guangzhou,southern China.In order to understand the characteristics of the reservoir eutrophication and population dynamics of cyanobacteria,phytoplankton of six small and medium sized reservoirs were sampled and analyzed in dry season（March to April） and wet season（July to August） of 2010.The results showed that Meizhou and Furongzhang reservoirs were oligo-mesotrophic;Sankeng,Baihualin and Helong reservoirs were meso-eutrophic,and Hongxiuquan reservoir was eutrophic.Their trophic state indices showed a little seasonal change.The trophic status indices were related to human activities in the catchments,increasing with hydraulic retention time.Affected by water temperature and water stability,cyanobacterial biomass had a marked seasonal variaiton.The biomass of cyanobacteria in the dry season ranged from 0.14-171.8 μg·L-1,accounting for the total biomass of phytoplankton of 0.1%-10.0%,the biomass of cyanobacterial in the wet season ranged from 0.013-32.8 mg·L-1,contributing 6.%-97.0% of total phytoplankton biomass.Due to low nutrient loading,biomass of cyanobacteria in Meizhou and Furongzhang reservoirs ranged from 0.1-16 μg·L-1,dominted by Limnothrix redekei,Anabaena pertuthate,Microcystis flos-aquae and Gloeocapsa sp..The biomass of cyanobacteria in Sankeng,Baihualin and Helong reservoirs ranged from 0.057-32.8 mg·L-1,dominated by Cylindrospermopsis raciborskii,Limnothrix redekei and Pseudanabaena limnetica.The biomass of cyanobacteria in Hongxiuquan reservoir ranged from 0.107 to 2.637 mg·L-1,dominted by Oscillatoria agardhii,Microcystis flos-aquae and Anabaena pertuthate.