Urban Resilience Across the Terrestrial-Aquatic Continuum
Authors
Emily B. Graham1,2* (emily.graham@pnnl.gov), Anna Turetcaia1, Andrew Townsend3, Izabel Stohel1, Young Song3, William Petersen3, Caroline Simonsen3, Rosalie Chu3, Jason Toyoda3, Stephanie Yarwood4, Dietrich Epp Schmidt5, Peter Groffman6,7, Michael Hanes7, Cora Potter7, Nicole G. Dix8, Hannah Ramage9, Matthew C. Ferner10
Institutions
1Earth and Biological Sciences Directorate, Pacific Northwest National Laboratory, Richland, WA; 2Washington State University, Richland, WA; 3Environmental Molecular Sciences Laboratory, Pacific Northwest National Laboratory, Richland, WA; 4College of Agriculture and Natural Resources, University of Maryland, College Park, MD; 5USDA Natural Resources Conservation Service, Hyattsville, MD; 6The City University of New York, New York, NY; 7Cary Institute of Ecosystem Studies, Millbrook, NY; 8Guana Tolomato Matanzas National Estuarine Research Reserve, Ponte Vedra Beach, FL; 9Lake Superior National Estuarine Research Reserve, University of Wisconsin–Madison Division of Extension, Superior, WI; 10Estuary and Ocean Science Center, San Francisco State University, Tiburon, CA
Abstract
The impacts of urbanization on ecosystem functions remain ambiguous, leading to uncertainty in urban carbon cycling within Earth systems models. To address this knowledge gap, the project investigates the overarching hypothesis that commonalities in microbial functions lead to distinct conserved biogeochemical processes in the urban environment. The team will present data-driven investigations of urban coastal resistance to precipitation across the United States and global urban soil microbiomes, as well as preliminary results from surveys of organic matter cycling in the Baltimore and Duluth-Superior metropolitan areas.
By calculating a resistance index based on dissolved oxygen, the project uncovers factors influencing coastal resistance to extreme precipitation at the continental scale and reveals that estuaries with higher urban influences seem to be more resistant to precipitation events—a result that is counter to the team’s initial hypothesis. At smaller scales, the factors influencing resistance interact with estuarine salinity and vary across individual estuaries, where researchers find relationships of resistance with additional factors. Considering escalating stressors along urban coastlines, these results are important for informing decisions regarding process-based model representations and estuarine water quality.
The project also uses existing urban soil microbiomes to assess changes in microbial phylogeny and functional potential across the urban environment and to derive a core urban microbiome for process-based model development. The team finds that functional potential is largely correlated to microbial phylogeny at the order-level, regardless of geographic location. Ubiquitous energy-generating pathways leverage the Calvin cycle as well as metabolisms based on nitrogen oxidation and reduction. Core organisms include many members of Pseudomonadota with diverse metabolisms, as well as archaea known to be involved in methane and nitrogen cycling.
Collectively, this project will create a unique knowledge set inclusive of control points, microbial decomposition processes, and their relationships to various urban attributes that influence the response of coastal zones to environmental extremes.