Discerning the roles of ocean acidification, eutrophication, and river alkalization in driving long-term pH trends in the Chesapeake Bay ...

• Main Author: Guo, Yijun
• Format: Text
• Language: English
• Published: Digital Repository at the University of Maryland 2022
• Subjects: Environmental science; Chesapeake Bay; Climate Change; Eutrophication; Modeling; Ocean acidification; River alkalinization
• Online Access: https://dx.doi.org/10.13016/mavd-f8in; https://drum.lib.umd.edu/handle/1903/28812

Rising anthropogenic CO2 in the atmosphere and oceanic uptake of CO2 have led to a gradual decrease in seawater pH and ocean acidification, but pH changes in estuaries and coastal systems are more complicated due to a multitude of global and regional environmental drivers. Increasing global fertilizer use due to agricultural production has led to a doubling of riverine nutrient loading since the 1950s, leading to widespread eutrophication in estuarine and coastal waters. Excessive nutrient loading stimulates primary production in the surface euphotic layer, which consumes CO2 and elevates pH, but unassimilated organic matter sinks and decomposes in bottom waters, producing CO2 and reducing pH. In the meantime, human-accelerated chemical weathering, such as acid rain and mining, has resulted in rising alkalinity in many rivers and basification in estuarine and coastal waters. To discern how these environmental drivers influence long-term pH trends in coastal waters, a coupled ...