| That ecosystems provide important benefits to society is well-established; that society has the capacity to quantify and evaluate complex trade-offs and interactions among ecosystem services and economic activities at management- and policy-relevant scales is not. This dissertation develops a spatially-explicit model of optimal renewable resource management that accounts for the value of ecosystem services. The model operationalizes the ecosystem service concept in a way that is both practical and theoretically rigorous. It poses the management problem as one of joint production of a renewable resource commodity and the ecosystem services affected by harvest. It incorporates economic and ecological heterogeneity of ecosystem services, including the renewable resource, and also accounts for potential interdependence across space and spatial scales. The theoretical framework applies to a broad spectrum of resources and ecosystems, and it adds coherence to a literature that spans renewable resource use, ecosystem-based management, integrated modeling, and the valuation of ecosystem services.;Practical feasibility is demonstrated with an application of the model to timber management in the Willamette River Basin, a forested watershed in the northwest United States. Utilizing GIS data and economic and ecological parameters from existing literature, the applied model optimizes harvest over time and space, accounting for the value of non-timber forest products, water yield, game species density, recreational amenities, and carbon. It addresses two important practical issues that arise in spatial, dynamic optimization problems such as this: non-convexity of benefits over time, and interdependence in the value of benefits across space. Model results indicate that the marginal value of many ecosystem services is sufficiently low, or their spatial distribution sufficiently limited, as to have little impact on optimal harvest decisions at the landscape scale, though they may affect optimal harvest decisions considerably in particular places. Moreover, trade-offs among services further mute their influence in the optimal harvest regime. However, benefits from carbon storage represent an important exception to the rule. Accounting for the value of carbon, whether alone or alongside other services, substantially changes optimal harvest decisions on nearly all stands and increases the economic value of the forested landscape---by as much as 50 percent relative to a management regime focused solely on maximizing timber profit, in the case of the Willamette River Basin. More broadly, the optimization exercise illustrates the challenges and feasibility of rigorously accounting for the value of ecosystem services in renewable resource management. |
