Impact of Wetlands Loss and Migration, Induced by Climate Change, on Chesapeake Bay DO Standards

A predictive wetlands module is added to an existing eutrophication model of Chesapeake Bay in order to evaluate the impact of wetlands loss and migration on dissolved oxygen (DO) standards. Loss and migration are expected due to increases in sea level associated with climate change. The module calculates fluxes of carbon, nitrogen, and phosphorus between wetlands and the adjacent water column. Calculations are performed for a range of sea-level increments up to 1 m. Wetlands areas, as a function of sea level, are obtained from an existing, independent, model applied to Chesapeake Bay. The results indicate two risks to DO standards. The first results from wetlands loss and simultaneous reductions in nutrient removal and burial by wetlands. Reduction in burial is the equivalent of a nutrient load increase and produces diminished DO in deep water and deep channel portions of the Bay. The second risk results from wetlands migration into upland areas adjoining shallow embayments and tidal fresh waters of the Bay. An increase in wetlands area in these regions may result in diminished DO concentration in adjacent open water due to direct wetlands respiration.

Automated summary

The addition of a predictive wetlands module to an existing eutrophication model in Chesapeake Bay evaluates the impact of wetlands loss and migration on dissolved oxygen standards. The results indicate two main risks to DO standards.