Nutrient budgets for the Bohai Sea: Implication for ratio imbalance of nitrogen to phosphorus input under intense human activities

Hongguan Li; Xiuren Li; Zehao Xu; Shengkang Liang; Yang Ding; Dehai Song; Hao Guo

doi:10.1016/j.marpolbul.2022.113665

Nutrient budgets for the Bohai Sea: Implication for ratio imbalance of nitrogen to phosphorus input under intense human activities

Mar Pollut Bull. 2022 Jun:179:113665. doi: 10.1016/j.marpolbul.2022.113665. Epub 2022 Apr 27.

Authors

Hongguan Li¹, Xiuren Li², Zehao Xu¹, Shengkang Liang³, Yang Ding⁴, Dehai Song⁴, Hao Guo⁵

Affiliations

¹ Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; College of Chemistry and Chemical Engineering, Ocean University of China, Qingdao 266100, China.
² College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, China.
³ Frontiers Science Center for Deep Ocean Multispheres and Earth System, and Key Laboratory of Marine Chemistry Theory and Technology, Ministry of Education, Ocean University of China, Qingdao 266100, China; Laboratory for Marine Ecology and Environmental Science, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266237, China. Electronic address: liangsk@ouc.edu.cn.
⁴ Key Laboratory of Physical Oceanography (Ocean University of China), Ministry of Education, and Qingdao National Laboratory for Marine Science and Technology, Qingdao, China.
⁵ National Marine Environment Monitor Center, Dalian 116000, China.

PMID: 35489091
DOI: 10.1016/j.marpolbul.2022.113665

Abstract

Eutrophication is a global problem for coastal ecosystems, one that the Bohai Sea (BHS), China, is severely afflicted by due to rapid economic and social development over the last forty years. For sustainable nutrients management in the BHS, comprehensive budgets for Nitrogen (N) and Phosphorus (P) was characterized in 2017, and the relative contributions of river input, submarine fresh groundwater discharge, atmospheric deposition, sediment diffusion, and exchange with the Yellow Sea were quantified. The annual N and P fluxes into the BHS were 362 × 10³ t and 10.4 × 10³ t, respectively. The terrigenous N inputs occupied the highest proportion, while the largest P input was from sediment diffusion. The ratio of N:P was 77 for total external inputs, while that of the Yellow River was 680; both exceeded the Redfield ratio, indicating an imbalance in the nutrient structure and a P limitation in the BHS.

Keywords: Bohai Sea; Nutrient budget; Redfield ratio; River input; Water exchange.

MeSH terms

China
Ecosystem
Environmental Monitoring
Human Activities
Humans
Nitrogen* / analysis
Nutrients
Phosphorus* / analysis
Rivers / chemistry

Substances

Phosphorus
Nitrogen