Effects of Seasonal Thermal Stratification on the Functional Diversity and Composition of the Microbial Community in a Drinking Water Reservoir

Abstract

Abstract:The microbial communities within reservoir ecosystems are shaped by water quality and hydrological characteristics. However, there are few studies focused on the effects of thermal stratification on the bacterial community diversity in drinking water reservoirs. In this study, we collected water samples from the Jinpen Reservoir around the re-stratification period. To explore the functional diversity and bacterial community composition, we used the Biolog method and 16S rRNA-based 454 pyrosequencing combined with flow cytometry. The results indicated that stratification of the reservoir had great effects on temperature and oxygen profiles, and both the functional diversity and the composition of the bacterial community strongly reflected the significant vertical stratification in the reservoir. The results of the Biolog method showed a significantly higher utilization of carbon sources in the hypolimnion than in the epilimnion. The result of pyrosequencing also showed a significantly higher species diversity and richness in the hypolimnion than in the epilimnion with different dominant phylum. Redundancy analysis also indicated that the majority of environmental variables, especially pH and dissolved oxygen, played key roles in shaping bacterial community composition. Our study provides a better understanding of the functional diversity of bacterial communities, and the response of microorganisms to seasonal thermal stratification. OPEN ACCESSWater 2015, 7 5526

Community Compositions of Phytoplankton and Eukaryotes during the Mixing Periods of a Drinking Water Reservoir: Dynamics and Interactions

“…Furthermore, trends of physicochemical factors were mainly consistent across all four depths, with the exception of turbidity. It was revealed that the spatial variation of all water quality parameters from October to December in Jinpen reservoir was not significant, resulting from Jinpen reservoir being in a mixed state during that period, with a similar vertical stratification of its physical and chemical factors [50]. Recently, Zhou et al [51] conducted field research onthe impact of a water-lifting aeration system on water quality and microbial community structure in a drinking water reservoir, and found that reservoir stratification was successfully eliminated due to the artificial mixing, which strongly affected environmental variables and obviously diminished differences of water quality between the bottom and surface.…”

“…Overall, Chao 1 indices were lowest in October and highest from November to December, ranging from 143 to 476. Moreover, the Chao 1 richness index was higher than the OTU value, indicating that more unidentified sequences are still to be studied in the reservoir [50]. Variations of Shannon diversity (H') were analogous to the Chao 1 index.…”

“…On the one hand, water temperature is the most important environmental factor affecting growth, development, community structure, quantity change, and the horizontal and vertical distribution of microbes in aquatic ecosystems [11]. On the other hand, the reservoir was at the natural mixed state during the studied period, which has an extreme influence on the entire functioning of the aquatic ecosystem [50,52]. Thus, phytoplankton in reservoirs are affected when the temperature of winter is the lowest of the whole year.…”

Farming and soil urban occupation in the water quality of Jaboticabal and Cerradinho streams

“…These results suggested a great and conserved diversity at the study sites. Recent studies in a water reservoir in China (Yang;Huang;Zhang, 2015) showed the effect of thermal stratification on bacterial communities. The authors explored the functional diversity and bacterial community composition using the Biolog method and 16S rRNA-based 454 pyrosequencing.…”

Effects of Hydrostatic Pressure on the Nitrogen Cycle of Sediment

“…The sediment microbial community has drawn great attention from microbial ecologists [18][19][20][21]. Moreover, the sediment host distinct microbial communities and their populations may strongly be affected by the nutritional status of water quality due to the variations of hydrological regime and other physical and chemical variables, including hydrostatic pressure [22][23][24][25].…”