Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.watres.2024.122445
Title (Primary) Climate-driven decline in water level causes earlier onset of hypoxia in a subtropical reservoir
Author Chen, H.; Luo, A.; Mi, C.; Lu, Y.; Xue, Y.; Jin, L.; Zhang, H.; Yang, J.
Source Titel Water Research
Year 2024
Department SEEFO
Volume 267
Page From art. 122445
Language englisch
Topic T5 Future Landscapes
Supplements https://ars.els-cdn.com/content/image/1-s2.0-S0043135424013447-mmc1.docx
Keywords Climate change; Monomicitic reservoir; Thermal stratification; Mixing; Phytoplankton
Abstract Hypoxia, especially in the bottom water, is occurring in deep and stratified reservoirs worldwide, threatening aquatic biodiversity, ecosystem functions and services. However, little is known about the timing of onset and ending of hypoxia, especially in subtropical reservoirs. Based on five-year (from April 2015 to January 2020) sampling of a subtropical monomicitic deep reservoir (Tingxi Reservoir) in southeast China, we found the evidence of about 40 days earlier onset of hypolimnion hypoxia during low water level periods in dry years compared to wetter high water level years. We explored the effects of stratification and mixing conditions on hypoxia, cyanobacterial biomass, and nutrient dynamics; and revealed the physical and biochemical conditions that drove hypoxia. The results indicated that 1) The decline in water level increased the intensity of thermal stratification, resulting in 40 days earlier onset of hypolimnion hypoxia in dry years than in wet years; 2) The decline in water level expanded the extent of hypoxia by promoting nutrient accumulation and phytoplankton biomass growth. 3) Warmer climate and less precipitation significantly promoted the risk of hypoxic expansion and endogenous phosphorus release in subtropical reservoirs. We suggest that more attention needs to be paid to the early onset of hypoxia and its consequences on water quality in subtropical stratified reservoirs during low water level periods due to climate-driven hydrological changes.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=29675
Chen, H., Luo, A., Mi, C., Lu, Y., Xue, Y., Jin, L., Zhang, H., Yang, J. (2024):
Climate-driven decline in water level causes earlier onset of hypoxia in a subtropical reservoir
Water Res. 267 , art. 122445 10.1016/j.watres.2024.122445