1. Regime shifts in trophic status and regional nutrient criteria for the Bohai Bay, China.
- Author
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Xie, Linping, Xu, Hanyue, Xin, Ming, Wang, Baodong, Tu, Jianbo, Wei, Qinsheng, and Sun, Xia
- Subjects
TERRITORIAL waters ,DISTRIBUTION (Probability theory) ,EUTROPHICATION control ,DATA quality ,TIME measurements ,PHOSPHORUS - Abstract
Identifying trophic status shift and developing nutrient criteria were considered important for controlling coastal eutrophication. Based on data from 1980 to 2018, we used sequential t -test analysis of regime shifts and assessment of coastal trophic status models to detect regime shifts in trophic status in Bohai Bay (China). We identified four distinct periods: unimpaired (1980–1984), minimally impacted (1985–1994), tipping point (1995–1999) and severely degraded (2000–2018). Using the reference conditions at different trophic status, a frequency distribution analysis was performed to develop candidate nutrient criteria. By considering other factors, such as the quantity and quality of data and long-term nutrient variations, we determined recommended criteria for dissolved inorganic nitrogen (15.3 μmol L
−1 ) and phosphorus (0.42 μmol L−1 ) in Bohai Bay. This study provides a novel and feasible approach to determine reference conditions for the determination of nutrient criteria for coastal waters. Regime shift in trophic status of Bohai Bay during different time periods. [Display omitted] • Four distinct periods of trophic status were identified in Bohai Bay in the past four decades. • The reference conditions were determined based on the combined results of STARS and ASSETS models. • The regionally specific nutrient criteria were developed for Bohai Bay. [ABSTRACT FROM AUTHOR]- Published
- 2021
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