[Objective] The aim was to study the relationship between chlorophyll-a and environmental impact factors in deep reservoir in Karst Areas.[Method] Taking Aha Reservoir for example,the changes of chlorophyll-a content ...[Objective] The aim was to study the relationship between chlorophyll-a and environmental impact factors in deep reservoir in Karst Areas.[Method] Taking Aha Reservoir for example,the changes of chlorophyll-a content and its relationship with environmental impact factors were researched,and the water quality of Aha Reservoir was assessed by means of modified Carlson trophic state index.[Result] Chlorophyll-a content in Aha Reservoir was higher in March,April,May and September and lower from June to August,and there was obvious seasonal variation,namely its variation trend was spring>summer>autumn>winter.In addition,chlorophyll-a content showed extremely significant correlation with transparency and dissolved oxygen (P<0.01) and significant correlation with ammonia nitrogen (P<0.05).Meanwhile,trophic state index was higher in whole year in Aha Reservoir which was in moderate trophic state in August,October and November and eutrophic state in other months.[Conclusion] The study could provide scientific reference for discussing the mechanism of lake eutrophication.展开更多
Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. Th...Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. This study was conducted to evaluate the water quality in the Aha Reservoir, Southwest China, focusing on cyanobacteria and cyanotoxins. Water samples were collected weekly or biweekly from May to September of 2015 and used to delineate temporal variations in density and distribution of toxic cyanobacteria and cyanotoxins in the reservoir. Toxic cyanobacteria identified consisted of Aphanizomenon flos-aquae, Pseudanabaena limnetica, Cylindrospermopsis sp., and Microcystis sp., with Aphanizomenon flos-aquae and Pseudanabaena limnetica being the most common and significant toxic genera. The total biomass of cyanobacteria was 17.0 mg/L. Identification and quantification of microcystin variants were conducted by high performance liquid chromatography(HPLC) using a system equipped with a photodiode array detector. Microcystin levels were between 0–3.0 μg/L, MC-RR was around 0–3.0 μg/L and MC-LR was approximately 0–0.9 μg/L. Overall, the results of this study indicate that the investigated reservoirs should be monitored regularly to minimize potential health risks to the human population.展开更多
In this paper, the relationship between sulfate reduction potential and mercury methylation potential was studied in the Aha, Baihua and Hongfeng reservoirs from Guiyang City. The methylmercury (MeHg) concentrations o...In this paper, the relationship between sulfate reduction potential and mercury methylation potential was studied in the Aha, Baihua and Hongfeng reservoirs from Guiyang City. The methylmercury (MeHg) concentrations of lake water in the Aha Reservoir were greatly elevated as compared to those of the Hongfeng and Baihua reservoirs, which was correlated with its distinctly high SRB abundance, SO42-, and S2- concentrations. Among the three reservoirs, however, the highest MeHg was observed in in the top several centimenters of pore water profile in the Hongfeng Reservoir where the lowest S2- in pore water occurred. The distributions of MeHg in lake water and pore water showed the highest methylation potential occurred at water-sediment surface for the Aha Reservoir and the in the top several centimenters of sediments for the Hongfeng Reservoir. It is guessed that the highest mercury methylation only occurs at the sites with certain sulfide concentrations.展开更多
基金Supported by Social Development Project of Guiyang City (2009304,2010503)
文摘[Objective] The aim was to study the relationship between chlorophyll-a and environmental impact factors in deep reservoir in Karst Areas.[Method] Taking Aha Reservoir for example,the changes of chlorophyll-a content and its relationship with environmental impact factors were researched,and the water quality of Aha Reservoir was assessed by means of modified Carlson trophic state index.[Result] Chlorophyll-a content in Aha Reservoir was higher in March,April,May and September and lower from June to August,and there was obvious seasonal variation,namely its variation trend was spring>summer>autumn>winter.In addition,chlorophyll-a content showed extremely significant correlation with transparency and dissolved oxygen (P<0.01) and significant correlation with ammonia nitrogen (P<0.05).Meanwhile,trophic state index was higher in whole year in Aha Reservoir which was in moderate trophic state in August,October and November and eutrophic state in other months.[Conclusion] The study could provide scientific reference for discussing the mechanism of lake eutrophication.
基金Supported by the Department of Science and Technology of Guizhou Province(Nos.[2015]2001,[2017]2863,[2018]5805)the Education Department of Guizhou Province(No.KY[2017]032)the Water Resources Department of Guizhou Province(No.KT201401)
文摘Toxic cyanobacteria(TCB) are well-known worldwide for their adverse impacts on humans. Species compositions and seasonal variations of TCB in reservoirs depend on interactions between physical and chemical factors. This study was conducted to evaluate the water quality in the Aha Reservoir, Southwest China, focusing on cyanobacteria and cyanotoxins. Water samples were collected weekly or biweekly from May to September of 2015 and used to delineate temporal variations in density and distribution of toxic cyanobacteria and cyanotoxins in the reservoir. Toxic cyanobacteria identified consisted of Aphanizomenon flos-aquae, Pseudanabaena limnetica, Cylindrospermopsis sp., and Microcystis sp., with Aphanizomenon flos-aquae and Pseudanabaena limnetica being the most common and significant toxic genera. The total biomass of cyanobacteria was 17.0 mg/L. Identification and quantification of microcystin variants were conducted by high performance liquid chromatography(HPLC) using a system equipped with a photodiode array detector. Microcystin levels were between 0–3.0 μg/L, MC-RR was around 0–3.0 μg/L and MC-LR was approximately 0–0.9 μg/L. Overall, the results of this study indicate that the investigated reservoirs should be monitored regularly to minimize potential health risks to the human population.
基金financially supported by Natural Science Foundation of China(Nos.41063006 and 40973083)"211 Project"Key Discipline Construction(KST2009003)the Guizhou Key Laboratory Construction Program(Qiankeheji-Z-[2012]4012)
文摘In this paper, the relationship between sulfate reduction potential and mercury methylation potential was studied in the Aha, Baihua and Hongfeng reservoirs from Guiyang City. The methylmercury (MeHg) concentrations of lake water in the Aha Reservoir were greatly elevated as compared to those of the Hongfeng and Baihua reservoirs, which was correlated with its distinctly high SRB abundance, SO42-, and S2- concentrations. Among the three reservoirs, however, the highest MeHg was observed in in the top several centimenters of pore water profile in the Hongfeng Reservoir where the lowest S2- in pore water occurred. The distributions of MeHg in lake water and pore water showed the highest methylation potential occurred at water-sediment surface for the Aha Reservoir and the in the top several centimenters of sediments for the Hongfeng Reservoir. It is guessed that the highest mercury methylation only occurs at the sites with certain sulfide concentrations.
