Thursday, August 6, 2009 - 8:40 AM

OOS 39-3: Complex ecosystem valuation: A study in the San Pedro and Rio Grande

David Brookshire1, Jennifer A. Thacher1, L. Arriana Brand2, Mark Dixon3, Karl Benedict1, Juliet Stromberg4, David C. Goodrich5, Craig D. Broadbent1, Molly McIntosh6, and Steven Stewart7. (1) University of New Mexico, (2) The University of Arizona, (3) University of South Dakota, (4) Arizona State University, (5) USDA-ARS-SWRC, (6) Bilingual Mediation, Facilitator and Interpreting LLC, (7) University of Arizona

Background/Question/Methods

Conservation of freshwater systems is critical in the semi-arid Southwest where groundwater and flood regimes strongly influence the abundance, composition, and structure of riparian (streamside) vegetation. At the same time these systems are in high demand for competing human use.  To address this conflict, natural scientists must evaluate how anthropogenic changes to hydrologic regimes alter ecological systems.  A broad foundation of natural science information is needed for ecological valuation efforts to be successful.  The goal of this research is to incorporate hydrologic, vegetation, avian, and economic models into an integrated framework to determine the value of changes in ecological systems that result from changes in hydrological profiles.  We have developed a hydro-bio-economic framework for the San Pedro River Region (SPRR) in Arizona that considers groundwater, stream flow, and riparian vegetation, as well as abundance, diversity, and distribution of birds within a protected area encompassing the San Pedro Riparian National Conservation Area (SPRNCA).  In addition, we are developing a similar framework for the Middle Rio Grande of New Mexico (MRG).   

Results/Conclusions

Distinct valuation studies using the non-market techniques of Choice Modeling (CM) and Contingent Valuation (CV) are being conducted for each site with benefit-transfer tests to be conducted between the two sites.  Conducting both CM and CVM questionnaires allows us to examine the each of the non-market techniques separately and for a comparison of the techniques.  This research is novel in that it provides much more detailed scientific information for economic valuation models than is typically available.  There are five research components for this project: (1) scenario specification and the hydrologic model, (2) the riparian vegetation model, (3) the avian model, (4) methods for displaying the information gradients in the survey instrument, and (5) the economic framework.  As such, our modeling framework begins with the identification of factors that influence spatial and temporal changes in riparian vegetation on the two rivers.  For the SPRR this is principally through impacts on the availability of surface water and groundwater, while in the MRG the impacts are through regulation of flooding and human restoration activities.  We use the construct of “current conditions” as a basis for making spatial predictions of vegetation change and avian populations in both river systems through linked modeling frameworks.  This framework utilizes the best available information through the direct focus on science-based linkages between flow regimes, habitat quality, birds, and human values. Results for the CV San Pedro Area will be presented.