Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays
Despite the fact that the water temperature of the Yangtze River has changed substantially due to the construction of Three Gorges Reservoir (TGR), little is known about how the thermal structure of TGR responded to the implementation of two large upstream reservoirs in 2013. We investigated the sea...
| Main Authors: | , , , , , , |
|---|---|
| Format: | Article |
| Language: | English |
| Published: |
Elsevier
2022-11-01
|
| Series: | Ecological Indicators |
| Subjects: | |
| Online Access: | http://www.sciencedirect.com/science/article/pii/S1470160X22009384 |
| _version_ | 1811337531082407936 |
|---|---|
| author | Lianghong Long Peng Chen Hui Xu Daobin Ji Liu Liu Zhengjian Yang Andreas Lorke |
| author_facet | Lianghong Long Peng Chen Hui Xu Daobin Ji Liu Liu Zhengjian Yang Andreas Lorke |
| author_sort | Lianghong Long |
| collection | DOAJ |
| description | Despite the fact that the water temperature of the Yangtze River has changed substantially due to the construction of Three Gorges Reservoir (TGR), little is known about how the thermal structure of TGR responded to the implementation of two large upstream reservoirs in 2013. We investigated the seasonal variations of water temperature and discharge in the middle reaches of the Yangtze River by analyzing multi-year (2004–2018) hydrological and water temperature data. The effects of upstream dams on the thermal regime, density currents and phytoplankton blooms in TGR were examined. The results show that water temperature in TGR increased in spring (+1.1 °C) and winter (+0.8 °C) seasons after the filling of upstream reservoirs compared to the years before. Longer duration of stratification is associated with a smaller discharge and a longer water residence time. Moreover, the increase of inflow, which was at least partially due to upstream dam construction, lead to the weakening of stratification during the spring season. As a consequence of the higher water temperature in TGR in spring, the density-driven exchange flows between the main reservoir and tributary bays have changed. Overflows became more frequent, which promoted the deepening of the surface mixing layer, and resulted in a dramatic reduction in the frequency and biomass of phytoplankton blooms in tributary bays of TGR. |
| first_indexed | 2024-04-13T17:56:25Z |
| format | Article |
| id | doaj.art-9f6a878576534bd7a48c1a5c726d43a8 |
| institution | Directory Open Access Journal |
| issn | 1470-160X |
| language | English |
| last_indexed | 2024-04-13T17:56:25Z |
| publishDate | 2022-11-01 |
| publisher | Elsevier |
| record_format | Article |
| series | Ecological Indicators |
| spelling | doaj.art-9f6a878576534bd7a48c1a5c726d43a82022-12-22T02:36:30ZengElsevierEcological Indicators1470-160X2022-11-01144109465Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary baysLianghong Long0Peng Chen1Hui Xu2Daobin Ji3Liu Liu4Zhengjian Yang5Andreas Lorke6Hubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, 443002 Yichang, China; Institute for Environmental Sciences, University of Koblenz-Landau, 76829 Landau, GermanyChongqing Branch, Changjiang River Scientific Research Institute, 400026 Chongqing, ChinaHubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, 443002 Yichang, ChinaHubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, 443002 Yichang, China; Corresponding authors.Yunnan Key Laboratory of Plateau Geographical Processes and Environmental Changes, Faculty of Geography, Yunnan Normal University, 650500 Kunming, ChinaHubei Field Observation and Scientific Research Stations for Water Ecosystem in Three Gorges Reservoir, China Three Gorges University, 443002 Yichang, China; Corresponding authors.Institute for Environmental Sciences, University of Koblenz-Landau, 76829 Landau, GermanyDespite the fact that the water temperature of the Yangtze River has changed substantially due to the construction of Three Gorges Reservoir (TGR), little is known about how the thermal structure of TGR responded to the implementation of two large upstream reservoirs in 2013. We investigated the seasonal variations of water temperature and discharge in the middle reaches of the Yangtze River by analyzing multi-year (2004–2018) hydrological and water temperature data. The effects of upstream dams on the thermal regime, density currents and phytoplankton blooms in TGR were examined. The results show that water temperature in TGR increased in spring (+1.1 °C) and winter (+0.8 °C) seasons after the filling of upstream reservoirs compared to the years before. Longer duration of stratification is associated with a smaller discharge and a longer water residence time. Moreover, the increase of inflow, which was at least partially due to upstream dam construction, lead to the weakening of stratification during the spring season. As a consequence of the higher water temperature in TGR in spring, the density-driven exchange flows between the main reservoir and tributary bays have changed. Overflows became more frequent, which promoted the deepening of the surface mixing layer, and resulted in a dramatic reduction in the frequency and biomass of phytoplankton blooms in tributary bays of TGR.http://www.sciencedirect.com/science/article/pii/S1470160X22009384Water temperatureReservoir operationThermal stratificationDensity currentPhytoplankton blooms |
| spellingShingle | Lianghong Long Peng Chen Hui Xu Daobin Ji Liu Liu Zhengjian Yang Andreas Lorke Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays Ecological Indicators Water temperature Reservoir operation Thermal stratification Density current Phytoplankton blooms |
| title | Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays |
| title_full | Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays |
| title_fullStr | Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays |
| title_full_unstemmed | Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays |
| title_short | Recent changes of the thermal structure in Three Gorges Reservoir, China and its impact on algal bloom in tributary bays |
| title_sort | recent changes of the thermal structure in three gorges reservoir china and its impact on algal bloom in tributary bays |
| topic | Water temperature Reservoir operation Thermal stratification Density current Phytoplankton blooms |
| url | http://www.sciencedirect.com/science/article/pii/S1470160X22009384 |
| work_keys_str_mv | AT lianghonglong recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays AT pengchen recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays AT huixu recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays AT daobinji recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays AT liuliu recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays AT zhengjianyang recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays AT andreaslorke recentchangesofthethermalstructureinthreegorgesreservoirchinaanditsimpactonalgalbloomintributarybays |