Grantee Research Project Results
2000 Progress Report: An Integrated Modeling Framework for Analyzing Wetlands Policies
EPA Grant Number: R827932Title: An Integrated Modeling Framework for Analyzing Wetlands Policies
Investigators: Wilen, James , Quinn, James
Current Investigators: Wilen, James , Quinn, James , Newbold, Stephen
Institution: University of California - Davis
EPA Project Officer: Chung, Serena
Project Period: October 1, 1999 through September 30, 2002
Project Period Covered by this Report: October 1, 1999 through September 30, 2000
Project Amount: $125,000
RFA: Decision-Making and Valuation for Environmental Policy (1999) RFA Text | Recipients Lists
Research Category: Environmental Justice
Objective:
The goal of this project is to create a framework for analyzing potential environmental and economic impacts of alternative wetlands management strategies. The research will culminate in a spatial optimization model that will be used to assess tradeoffs between several important ecosystem services that wetlands can support in the Central Valley of California in the context of a fixed management budget. The project consists of two stages: (1) estimating relationships between landscape configuration and the provision of key ecosystem services from wetlands?habitat for key species of concern, water quality enhancement, and flood management benefits; and (2) incorporating these functions, along with functions describing the economic costs of management, into a spatial optimization model that will allow an analyst to determine the optimal configuration of management decisions in a study area.Progress Summary:
In the first year of research, we have developed a spatial optimization model and applied it to a stylized landscape representative of watersheds in the Central Valley of California. We have applied the model to the hypothetical landscapes in a number of simulation exercises, and we have made important progress towards determining the ultimate applicability of the framework.Results of the simulation exercises demonstrate several important points regarding multi-objective decision-making in a spatially interdependent landscape. First, the only way to guarantee cost-effective management is with a strategy that takes into account all of the spatial interdependencies that affect the provision of ecosystem services, and considers how management decisions in each location affect the benefits of management at all other locations. Heuristics based on loose indicators of overall levels of ecosystem functions usually will result in suboptimal levels of ecosystem services, even if total wetland area is maximized.
Second, the performance of suboptimal heuristics, which may be the only feasible means of approaching large problems in the real world, depends in part upon the initial configuration of the landscape. Furthermore, sensitivity analyses demonstrate the importance of the magnitude of the spatial effects on the provision of ecosystem services. For example, a negative effect of wetland edges may be biologically significant for a particular species of concern in the region, but, if they are not sufficiently large, then optimum habitat conditions may be provided by restoring several, inexpensive unconnected wetland patches as opposed to fewer, more costly contiguous patches.
Third, effective management depends not only upon the nature of the processes that determine the level of ecosystem services, but also upon the degree to which the costs of conservation depend on the location and configuration of managed patches. The cost structure is an ingredient that often is lacking in site selection models. An integrated analysis that combines both the relevant ecology and economics is required here, and the framework we are developing will provide this capability.
We currently are near completion of our first set of models of ecosystem services?those that relate to habitat quality for several bird species in the study area. These results will provide the foundation for specifying the production function for habitat quality necessary for the spatial optimization model in the final phase of the project.
We are using regression models to explain the variation in the abundance of birds counted at survey sites throughout the region by the landscape characteristics around each survey location. One of the notable features of the statistical models?and one that is essential for subsequent analyses of the impacts of wetlands management decisions?is the inclusion of measures of landscape configuration. For decisionmaking purposes, we need to know how the total area of wetlands and other land use types affect habitat quality, and how the configuration of wetland patches?in relation to each other and to other types of land?affects overall habitat quality. For many of the modeled species, measures of fit for the Poisson regression models are promising, and parameter estimates generally are in accord with what is known about the species' habitat preferences on a qualitative level.
We also are attempting to determine the scale at which measures of landscape characteristics best predict bird abundances. These results will be of ecological interest in their own right, and they will help to determine the robustness of the habitat preference models. Furthermore, there is substantial variance in the effects of landscape configuration across species, which supports the notion that a one-size-fits-all approach to modeling habitat quality would be inappropriate. It is still an open question, however, and one that is central to the overall project, how this variability in habitat preferences across species will translate into variability in management recommendations.
Future Activities:
In the remainder of this second year of the project, we are completing the habitat quality modeling and estimating relationships between landscape configuration and water quality and expected flooding damages. Whereas our models of habitat quality are based on statistical analyses of species and land use distributions, models of the hydrologic functions will be based on appropriately condensed versions of one or more readily available process models calibrated to conditions in the study area. The challenge in this phase of the project is to translate the complex nonlinear relationships embodied in the process models into a form that can be utilized by our spatial optimization model. Tradeoffs between the mathematical integrity of the original models and the solvability of the final optimization model will be paramount here.In the final year of the project, we will complete the hydrologic (meta) models and estimate management costs. The costs of purchasing parcels for wetlands restoration will be estimated by assessed land values, and restoration costs will be estimated with data from state and federal agencies that have supported and led restoration efforts in the region. Finally, the models of ecosystem services and management costs will be incorporated into the spatial optimization framework that we already have developed, and a number of management scenarios will be analyzed.
Journal Articles:
No journal articles submitted with this report: View all 3 publications for this projectSupplemental Keywords:
ecosystem indicators, watersheds, habitat, aquatic, public policy, cost benefit, nonmarket valuation, public good, social science, socioeconomic., RFA, Scientific Discipline, Economic, Social, & Behavioral Science Research Program, Water, Geographic Area, Ecosystem Protection/Environmental Exposure & Risk, Nutrients, Ecosystem/Assessment/Indicators, Ecosystem Protection, State, Ecological Effects - Environmental Exposure & Risk, Environmental Monitoring, Ecological Risk Assessment, Ecology and Ecosystems, decision-making, Ecological Indicators, Economics & Decision Making, aquatic ecosystem, remote sensing, ecological exposure, wetland policies, wetlands, policy analysis, nutrient sensitive ecosystems, computer simulation model, integrated modeling, San Francisco, flood management, non-market valuation, socioeconomics, cost/benefit analysis, ecosystem restoration, water quality, aquatic ecosystems, wildlife habitat, public policy, wetlands preservation, California (CA), land use, benefits assessment, environmental risk assessmentProgress and Final Reports:
Original AbstractThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.