Models for quantifying ecological benefits for use in a natural resources marketplace: Promise and problems

Background/Question/Methods

While notable successes have helped turn the tide on environmental degradation, in many cases, problems persist despite regulations and restoration efforts.  There is broad recognition that incentive-based frameworks, based on the concept of payments for ecosystem services, may help achieve goals for environmental protection and enhancement where a solely regulatory approach has failed.  We reviewed potential models that can be used to translate specific management actions on the landscape into quantifiable benefits that could be rewarded, incentivized or traded in a nascent natural resources marketplace in Whatcom County, Washington.  We focused on models for assessing three broad categories of ecological benefits in watersheds: water quality, water quantity, and habitat (primarily for anadromous fish).  In looking for win-win opportunities and more transparency in assessing agriculture-watershed tradeoffs, we also assessed metrics for quantifying direct benefits for agriculture as a result of specific actions – both to individual farmers and broader regional goals of maintaining an active agricultural economy.    We ranked models based on several criteria influencing their potential utility for ecosystem service accounting in a marketplace context, including availability of a model for rapid adoption, relevance to and accuracy in local watersheds, sensitivity to important actions, and ease of use. 

Results/Conclusions

We found a number of models for quantifying watershed enhancement benefits for several priority watershed parameters of concern, including nutrients, sediment, temperature, and wetland function.  However, many agricultural and watershed enhancement benefits proved more problematic to quantify. For these, no models immediately met our criteria sufficiently to allow use without substantially more development.  For example, for water quantity benefits for both agricultural and watershed enhancement, the hydrologic and flood models currently used by local governments typically do not achieve the level of spatial sensitivity necessary to account for beneficial actions at the site-scale.  Similarly, while there is substantial interest in quantifying benefits of riparian restoration for salmon habitat, all the models reviewed had at least one significant drawback for our purposes.  Overall, a plethora of models exist, but finding those that are sensitive to the most likely management actions at the site-scale, are well-tested and validated, and run on easily available data remains challenging for several important environmental benefits.