Skip Links

USGS - science for a changing world

Scientific Investigations Report 2012–5070

National Water-Quality Assessment Program

Representation of Regional Urban Development Conditions Using a Watershed-Based Gradient Study Design

By Silvia Terziotti, Gerard McMahon, and Amanda H. Bell

ABSTRACT

As part of the U.S. Geological Survey National Water-Quality Assessment Program, the effects of urbanization on stream ecosystems (EUSE) have been intensively investigated in nine metropolitan areas in the United States, including Boston, Massachusetts; Atlanta, Georgia; Birmingham, Alabama; Raleigh, North Carolina; Salt Lake City, Utah; Denver, Colorado; Dallas–Fort Worth, Texas; Portland, Oregon; and Milwaukee–Green Bay, Wisconsin. Each of the EUSE study area watersheds was associated with one ecological region of the United States. This report evaluates whether each metropolitan area can be generalized across the ecological regions (ecoregions) within which the EUSE study watersheds are located. Seven characteristics of the EUSE watersheds that affect stream ecosystems were examined to determine the similarities in the same seven characteristics of the watersheds in the entire ecoregion. Land cover (percentage developed, forest and shrubland, and herbaceous and cultivated classes), average annual temperature, average annual precipitation, average surface elevation, and average percentage slope were selected as human-influenced, climate, and topography characteristics. Three findings emerged from this comparison that have implications for the use of EUSE data in models used to predict stream ecosystem condition. One is that the predominant or "background" land-cover type (either forested or agricultural land) in each ecoregion also is the predominant land-cover type within the associated EUSE study watersheds. The second finding is that in all EUSE study areas, the watersheds account for the range of developed land conditions that exist in the corresponding ecoregion watersheds. However, six of the nine EUSE study area watersheds have significantly different distributions of developed land from the ecoregion watersheds. Finally, in seven of the nine EUSE/ecoregion comparisons, the distributions of the values of climate variables in the EUSE watersheds are different from the distributions for watersheds in the corresponding ecoregions.

Revised August 29, 2012

First posted May 24, 2012

For additional information contact:
Director
USGS North Carolina Water Science Center
3916 Sunset Ridge Road
Raleigh, NC 27607
phone: (919) 571–4000

Part or all of this report is presented in Portable Document Format (PDF); the latest version of Adobe Reader or similar software is required to view it. Download the latest version of Adobe Reader, free of charge.


Suggested citation:

Terziotti, Silvia, McMahon, Gerard, and Bell, A.H., 2012, Representation of regional urban development conditions using a watershed-based gradient study design: U.S. Geological Survey Scientific Investigations Report 2012–5070, 109 p.



Contents

Foreword

Abstract

Introduction

Purpose and Scope

Methods

Ecoregion Watershed Delineation

Methods of Comparison

Results

Portland

Salt Lake City

Denver

Dallas

Milwaukee

Birmingham

Atlanta

Raleigh

Boston

Discussion

Background Land Cover is Either Forested or Agricultural

Representativeness of the EUSE Urban Gradient Relative to the Gradient for the Entire Ecoregion

Climate Zones

Conclusions

Acknowledgments

References

Appendix 1—Study watersheds in nine metropolitan areas used in the effects of urbanization on stream ecosystems study


Accessibility FOIA Privacy Policies and Notices

Take Pride in America logo USA.gov logo U.S. Department of the Interior | U.S. Geological Survey
URL: http://pubs.usgs.gov/sir/2012/5070/
Page Contact Information: GS Pubs Web Contact
Page Last Modified: Thursday, January 10, 2013, 07:54:59 PM