2015 GSA Annual Meeting in Baltimore, Maryland, USA (1-4 November 2015)

Paper No. 276-2
Presentation Time: 8:25 AM


KAUSHAL, Sujay S., Department of Geology and Earth System Science Interdisciplinary Center, University of Maryland, College Park, MD 20740, MCDOWELL, Willam H., Dept. of Natural Resources & the Environment, University of New Hampshire, 56 College Rd, Durham, NH 03824, WOLLHEIM, Wilfred M., Earth System Research Center, University of New Hampshire, Morse Hall, 8 College Road, Durham, NH 03824, JOHNSON, Tamara Newcomer, U.S. Environmental Protection Agency, Washington DC, DC 20460, MAYER, Paul M., Office of Research and Development, National Risk Management Research Laboratory, U.S. Environmental Protection Agency, Ada, OK 74820, BELT, Kenneth T., US Department of Agriculture Forest Service, Northern Research Station, Baltimore, MD 21228 and PENNINO, Michael J., Department of Civil and Environmental Engineering, Princeton University, Princeton, NJ 08544, skaushal@umd.edu

The structure, function, and services of urban ecosystems evolve over time scales from seconds to centuries as Earth’s population grows, infrastructure ages, and management decisions alter them. The concept of “urban evolution” was proposed in order to study changes in urban ecosystems over time. Urban evolution has exerted a major influence on Earth's water and elemental cycles from local to global scales over human history. An understanding of urban evolution allows urban planning, management, and restoration to move beyond reactive management to predictive management. We explore two key mechanisms of urban evolution, urban selective pressure and adaptation, and their relationship to the evolution of modern water and biogeochemical cycles. Urban selective pressure is an environmental or societal driver contributing to urban adaptation. Urban adaptation is the sequential process by which an urban structure, function, or services becomes more fitted to its changing environment or human choices. We show how hydrological and biogeochemical traits evolve across successive generations of urban ecosystems via shifts in urban selective pressures and adaptations. We also discuss how urban evolution can be divided into distinct stages and transition periods of growth and expansion and decay and repair during the Anthropocene epoch. We explore multiple examples and drivers of urban evolution and adaptations including the role of unintended consequences and societal drivers. We present a conceptual model for the evolution of urban waters from the Industrial Revolution to the present day emphasizing the role of urban adaptations in response to selective pressures. Finally, we conclude by proposing new concepts and questions for future research related to the urban evolution of water, material, and energy cycles.