Oyster farming control on phytoplankton bloom promoted by thermal discharge from a power plant in a eutrophic, semi-enclosed bay

Zhibing Jiang; Ping Du; Yibo Liao; Qiang Liu; Quanzhen Chen; Lu Shou; Jiangning Zeng; Jianfang Chen

doi:10.1016/j.watres.2019.04.023

Oyster farming control on phytoplankton bloom promoted by thermal discharge from a power plant in a eutrophic, semi-enclosed bay

Water Res. 2019 Aug 1:159:1-9. doi: 10.1016/j.watres.2019.04.023. Epub 2019 Apr 13.

Authors

Zhibing Jiang¹, Ping Du², Yibo Liao³, Qiang Liu⁴, Quanzhen Chen⁴, Lu Shou⁵, Jiangning Zeng⁶, Jianfang Chen³

Affiliations

¹ Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
² Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; Function Laboratory for Marine Fisheries Science and Food Production Processes, Pilot National Laboratory for Marine Science and Technology (Qingdao), Qingdao, China.
³ Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China; State Key Laboratory of Satellite Ocean Environment Dynamics, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
⁴ Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China.
⁵ Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China. Electronic address: shoulu981@sio.org.cn.
⁶ Key Laboratory of Marine Ecosystem and Biogeochemistry, State Oceanic Administration, Second Institute of Oceanography, Ministry of Natural Resources, Hangzhou, China. Electronic address: zjn@sio.org.cn.

PMID: 31075499
DOI: 10.1016/j.watres.2019.04.023

Abstract

Temperature increase caused by thermal discharge from power plants promotes phytoplankton growth and frequent bloom in eutrophic subtropical waters, particularly in cold seasons. Suspension filter-feeding bivalves show size-selective grazing on phytoplankton. Thus, we hypothesized that algal bloom under thermal stimulation could be controlled and that phytoplankton community was structured by oyster farming. Here, ten cruises were conducted in two oyster farms (OFs) and control areas (CAs) adjacent to the Ninghai Power Plant in the upper section of Xiangshan Bay during 2009-2015. We found that thermal discharge induced severe winter algal blooms. Phytoplankton abundance and chlorophyll a (chla) were significantly lower (46.3% and 28.3%, respectively) in OF than in CA, indicating a high filtration efficiency by oysters and the associated biofouling assemblages. In addition, oyster farming significantly increased species richness (by 26.3%), Shannon-Wiener diversity (by 38.3%), and Pielou's evenness indices (by 28.8%) and reduced suspended solids (by 12.2%), total organic carbon (by 18.4%), dissolved inorganic nitrogen (by 1.5%), and phosphorus (by 3.7%). Furthermore, oyster farming considerably reduced (increased) micro-chla contribution (pheophytin/chla) by 34.8% (71.1%), suggesting a strong size-selective grazing on phytoplankton. Analysis of similarity revealed a significant difference in phytoplankton community composition between OF and CA. However, after the removal of culture rafts, all the abundance, chla, species diversity, dominant species, size structure, and community composition of phytoplankton showed no significant difference. Our study demonstrated that oyster farming effectively alleviated eutrophication and algal bloom and enhanced phytoplankton diversity, which provides guidance for aquaculture and ecological restoration in subtropical coastal eutrophic waters.

Keywords: Oyster farming; Phytoplankton; Size-selective grazing; Species diversity; Thermal discharge; Xiangshan bay.

MeSH terms

Animals
Bays
Chlorophyll A
Eutrophication
Ostreidae*
Phytoplankton*
Power Plants
Seasons

Substances

Chlorophyll A