oEPA
science in ACTION
BUILDING A SCIENTIFIC FOUNDATION FOR SOUND ENVIRONMENTAL DECISIONS
www.epa.gov/ord
ECOLOGICAL
RESEARCH PROGRAM
LANDSCAPE INDICATORS ASSIST GROWTH MANAGEMENT DECISIONS
Issue:
The landscape changes to our
forests, grasslands, and plants can
indicate how humans and natural
conditions are impacting the
environment. Over the last
century, vegetation changes have
been recorded anecdotally by
comparing historical records or
photographs, but these methods
have provided only a snapshot.
New tools and methods are needed
to provide a comprehensive
analysi s of landscape changes over
a wide region and how the
changes are impacting natural
resources such as the supply of
water.
Science Objective:
Scientists at the U.S.
Environmental Protection
Agency's Office of Research and
Development are using earth-
observing satellites and process
models to quantitatively measure
comprehensive changes in
landscape and forecast how
specific land management actions
will impact the environment.
Landscape indicators have been
developed for the San Pedro
River, a moderate-sized watershed
in southeast Arizona and northern
Sonora, Mexico, to estimate the
status of watershed conditi ons, the
sustainability of water supply, and
the condition of habitats.
Scientists developed a spatial
analysis tool known as Automated
Geospatial Watershed Assessment
(AGWA) to understand how the
changes in vegetation are
impacting the overall San Pedro
watershed. AGWA has been used
to evaluate future conditions
associated with changes in land
cover and land use.
Application and Impact:
The forecasting tools and methods
developed are providing a
landscape approach to
environmental planning and
protection for communities.
Researchers are able to compare
and display how potential growth
scenarios will impact the
environment, water supply, and
quality of life. Local planners are
using the science to evaluate
alternative growth management
strategies.
References:
Kepner, W.G.; Semmens, D.J.; Bassett, S.D.;
Mouat, D.A. and Goodrich, D.C. Scenario Analysis
for the San Pedro River, Analyzing Hydrological
Consequences of a Future Environment. Journal of
Environmental Monitoring and Assessment. 2004
94: 115-127. Kluwer Academic Publishers.
http://dx.doi.Org/10.1023/B:EMAS.0000016883.10
110.15
Kepner, W.G.; Edmonds, C.M. and Watts, C.J.
Remote Sensing and Geographic Information
Systems for Decision Analysis in Public Resource
Administration: A Case Study of 25 Years of
Landscape Change in a Southwestern Watershed.
U.S. Environmental Protection Agency,
EPA/600/R-02/039, 2002.
For more information, visit:
www.epa.gov/nerlesdl/land-sci/san-pedro.htm
www.epa.gov/nerlesdl/land-sci/agiva/index.htm
Contact:
William G. Kepner, research ecologist, EPA's
Office of Research and Development, 702-798-
2193, or kepner. william@,epa. gov.
June 2007
U.S. Environmental Protection Agency
Office of Research and Development

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