Two original computer simulation models are presented in this thesis. Although these models differ in their temporal, spatial, and structural dimensions, they are unified by a common purpose: to build quantitative understanding of environmental resources and better inform their future management. According to the U.S. Department of the Interior’s Minerals Management Service, there are significant undiscovered reserves of oil and natural gas located in the Gulf of Mexico Outer Continental Shelf region. While the existence of these energy resources is critical to the nation’s future economic well-being, of equal importance is the amount of already extracted energy that will be required to deliver the new fuel to society in a useful form; the difference between the two quantities is the net energy supply. “Energy return on investment” (EROI) is an indicator of the net productivity of an energy supply process; specifically, it is the ratio of gross energy production to total, direct plus indirect, energy cost. Chapter 1 describes a dynamic model designed to calculate the EROI of offshore energy extraction in the U.S. Gulf of Mexico from 1985 to 2004 under differing assumptions regarding energy cost and technology. In 2004, the EROI of the process is estimated to range from 10 to 25 depending on how comprehensively energy costs are defined. In comparison, the EROI of U.S. onshore petroleum extraction in the 1930s was at least 100. Ecosystem services are those functions of ecosystems that support, directly or indirectly, human welfare. Although interest in ecosystem services has surged in recent decades and is currently still on the rise, these phenomena have yet to be universally quantified. The current Multi-scale, Integrated Models of Ecosystem Services (MIMES) project is an ambitious attempt to do so through dynamic, spatially explicit modeling. As a part of this broad initiative, Chapter 2 details the development and testing of a model designed to measure and map the ecosystem service “water regulation” at multiple scales. The model is an extension of the well known and widely used “runoff curve number” method originally developed by the U.S. Department of Agriculture; it is applied to the Winooski watershed (Vermont, U.S.A.) and to the entire globe.

Ecosystem services are the benefits people obtain from ecosystems. Ecosystem service valuation (ESV) is the process of assessing the contributions of ecosystem services to human well-being. Its goal is to express the effects of changes in ecosystem services in terms of trade-offs against other things that also support human welfare. Ecologists tend to use biophysical-based methods while economists have developed preference-based tools for ESV. In this dissertation I attempt to bridge these two worlds by writing six papers using methods and insights from both disciplines. In paper 1, my coauthors and I (thereafter “we”) reviewed (1) what has been done in ESV research in the last 45 years; (2) how it has been used in ecosystem management; and (3) prospects for the future. One conclusion is that researchers and practitioners will have to transcend disciplinary boundaries and synthesize methodologies and tools from various disciplines in order to meet the challenge of ecosystem service valuation and management. Ninety-four peer-reviewed environmental economic studies were used to value ecosystem services in the State of New Jersey in paper 2. We translated each benefit estimate into 2004 US dollars per acre per year, computed the average value for a given eco-service for a given ecosystem type, and multiplied the average by the total statewide acreage for that ecosystem. The total value of these ecosystem services was estimated as $11.6 billion/year and we believe that this result is conservative. This aggregate value of New Jersey’s ecosystem services is a useful, albeit imperfect, basis for assessing and comparing these services with conventional economic goods and services. In paper 3 we present a conceptual framework for non-market valuation of ecosystem services provided by coastal and marine systems and review the peer-reviewed literature in this area. Next we selected a subset of this literature and conducted the first meta-analysis of the ecosystem service values provided by the costal and nearshore marine systems in paper 4. Using regression we found that over 75% of the variation in willingness to pay (WTP) for coastal ecosystem services could be explained. Our metaregression models also predicted out-of-sample WTPs and showed that the overall average transfer error was 24%, with 40% of the sample having transfer errors of 10% or less, and only 2.5% of predictions having transfer errors of over 100%. In the final two papers our focus is on the linkage between biodiversity and ecosystem function (BEF) which connects ecosystems with human welfare. In paper 5 we first present an overview of the main concepts and findings from a decade of the BEF literature. After a discussion on how agrobiodiversity relates to stability and resilience in agricultural systems at both the species and the landscape scales, we conclude with observations on the research needs in assessing the BEF relationship and the implications for agrobiodiversity ESV research. Finally, in paper 6, by using multiple regression analysis at the site and ecoregion scales in North America, we estimated relationships between biodiversity (using plant species richness as a proxy) and Net Primary Production (NPP, as a proxy for ecosystem services). We tentatively conclude that a 1% change in biodiversity in the high temperature range (which includes most of the world’s biodiversity) corresponds to approximately a 1/2% change in the value estimate of ecosystem services.

Accurate estimation of the responses of understory plants to natural and anthropogenic disturbance is essential for understanding efficacy and non-target effects of management and restoration activities. However, ability to assess changes in abundance of understory plants that result from disturbance may be hampered by inappropriate sampling methodologies. Conventional methods for sampling understory plants may be robust for common, well-distributed species, but may fail to adequately characterize the abundance of less-common species, which are often the taxa of management concern. I tested conventional and novel approaches to sampling understory plants to determine their efficacy (in terms of number of replicates and time required) for quantifying abundance of plants of varying frequency and spatial heterogeneity on three control and three thinned-and-burned treatment units located within the western Montana block of the Fire and Fire Surrogates Project (FFS) a large-scale investigation of the effects of fuel-hazard reduction treatments on a variety of ecosystem components. In each treatment unit, I used four sampling methods (modified Whittaker plots, Daubenmire transects, point line intercept transects, and strip adaptive cluster sampling) to estimate the cover of 24 understory species that vary in abundance. Compared to Daubenmire and point line intercept transects, modified Whittaker plots estimated cover with the lowest variances and, consequently, for the majority (67%) of species required the smallest sample sizes to accurately measure cover. However, this greater sampling efficiency was offset by increased time required to sample. For species grouped by growth-form and for common species, all three conventional sampling designs (i.e. Daubenmire transects, modified Whittaker plots, and point line intercept transects) were capable of estimating cover with a 50% relative margin of error with reasonable sample sizes (3-36 plots or transects for growth-form groups; 8-14 for common species); however, increasing the precision to 25% relative margin of error required sampling sizes that may be logistically infeasible (11-143 plots or transects for growth-form groups; 28-54 for common species). In addition, all three designs required enormous sample sizes to estimate cover of non-native species as a group (29-60 plots or transects) and of individual less-common species (62-118 plots or transects), even with 50% relative margin of error. Strip adaptive cluster sampling was the only method tested that efficiently sampled less-common species: for Cirsium arvense, an invasive non-native plant, adaptive sampling required five times fewer replicates than needed for modified Whittaker plots and 20 times less than for Daubenmire or point line intercept transects. My findings suggest that conventional designs may not be effective for accurately estimating the abundance of newly establishing, non-native plants as a group or of the majority of forest understory plants, which are characterized by low abundance and spatial aggregation. Novel methods such as strip adaptive cluster sampling should be considered in investigations for which cover of these species is a primary response variable.

Nitrogen (N) is a primary limiting nutrient in all ecosystems. Therefore, a thorough understanding of N cycling processes in forest ecosystems is required to minimize N losses to fire, harvesting, and other forms of land management. The influence of fire, fire exclusion and forest restoration treatments on non-symbiotic N-fixation in the forest ecosystem has been poorly studied. Over the past 100 years, fire has been greatly excluded from low elevation, fire maintained forests as a result of active fire suppression as well as land management activities that create discontinuities in landscape fire patterns. Previous studies have shown this activity to inhibit recolonization of sites by symbiotic N-fixing plant species. The lack of these important N fixing species may make non-symbiotic, free-living N fixing bacteria a more important source for N recovery in these forest ecosystems following disturbance. Recent studies also suggest that free-living N-fixing bacteria colonizing decomposing woody roots have the capacity to fix large amounts of N. The purpose of these studies was to investigate the effect of fire, fire exclusion, and forest restoration on the N contribution of non-symbiotic N-fixing bacteria (colonizing soil, woody roots, and soil crusts) to the forest ecosystem and how their contribution compares to symbiotic N-fixers in Western Montana. Studies were conducted in the laboratory and at numerous field sites throughout western Montana. In order to determine the N-fixation activity of organisms in these systems, we used the acetylene reduction technique. Neither time since fire, nor restoration treatment had any direct influence on free living N-fixation in soil or woody roots. Moisture and N availability were the potent drivers of free living N-fixation in western Montana. Nitrogen-fixation rates were low in decomposing woody roots in these ecosystems and woody roots do not contribute a significant amount of N to low elevation ponderosa pine/Douglas-fir forests in western Montana. Free-living N-fixing bacteria in soils were found to make a significant, yet modest N contribution to the forest ecosystem. Nitrogen demand by trees and shrubs are being maintained by residual soil organic N, symbiotic N fixation, and wet and dry N deposition in the Inland Northwest

Thesis (Ph.D.)--University of Vermont, 2009. / Includes bibliographical references (leaves 233-239).

Thesis (Ph. D.)--Drexel University, 2004. / Includes abstract and vita. Includes bibliographical references (leaves 192-199).

Thesis (M.S.)--Oregon State University, 2002. / Typescript (photocopy). Includes bibliographical references (leaves 85-98). Also available on the World Wide Web.

The thesis addresses the question of how to establish an appropriate methodology for monitoring sustainable tourism development (STD) in Samoa, an independent small island state in the South Pacific. The theoretical starting point and common thread throughout this study is that sustainable development can and must form the paramount context for STD. The author adopts an interdisciplinary approach, drawing on innovative research in the field of ecology and ecosystem management in order to gain understanding of new and emerging interpretations of sustainability and their implications for STD. Three guiding principles are identified and consequently form the conceptual foundation for the work. That understanding and implementing STD requires: i) a comprehensive systemic approach; ii) a stakeholder-driven focus; and iii) the adaptive capacity to accommodate the non-linear behaviour of complex systems. These principles are tested in the context of the development of a place-based STD monitoring programme in Samoa. In collaboration with the Samoa Visitors Bureau (SVB) and a multidisciplinary stakeholder committee, a set of STD objectives for Samoa were formulated, 20 indicators were identified to monitor progress towards their achievement, and a monitoring programme was established to utilise the results. The objectives and corresponding indicators are broad in their coverage of tourism and sustainable development issues, have stakeholder resonance, and are feasible considering the technical and human capacity currently available in SVB. The monitoring programme also has the flexibility to adapt to change as it inevitably occurs. The work undertaken in Samoa demonstrates that as well as generating timely information on the current state of STD, if a stakeholder approach is adopted, monitoring can also provide the opportunity for considerable social learning, and help bridge the gap between indicator development and indicator use, ensuring indicator results are actually used to change the way tourism is planned, developed and managed.

Adaptive Management (AM) is an “approach to managing natural resources that emphasizes learning from the implementation of policies and strategies” (Allan & Curtis, 2005). The approach involves the monitoring and evaluation of hypotheses regarding system responses and/or the success of individual projects followed by integration of the findings into future efforts. It can be characterized as active (focused upon testing hypotheses) or passive (focused upon implementation). AM has been used by several federal and state agencies for the implementation of large-scale restoration efforts. This paper explores the use of AM in two large, regional water resources projects with state and federal agency involvement and significant ecological and economic resources at risk without intervention: the Sacramento-San Joaquin Bay Delta in California and the Everglades Restoration in Florida. The paper explores potential avenues for further improvement of the AM efforts with an emphasis on: governance; establishment of networks to aid adaptive management, provisions for funding especially for active AM; cost-benefit analyses; and delegation of authority to allow for implementation of adaptive management. / text

This thesis applies mixed ethnographic methods at field sites in British Columbia and the United Nations to explore the spread and uptake of the "ecosystem services" idea in different institutions of environmental governance. I explore intensifying efforts by ecosystem services proponents to rearticualte living nature in various ways and with various objectives around the concept. As the idea manifests in a wide array of different policies and practices, I attempt to characterize a process of 'discursive refraction,' and argue ecosystem services represents a kind of chimera, appearing differently to the disparate practitioners interpreting, responding to, and beginning to use it. Consequently, the idea takes on diverse forms and functions in those institutional settings where it appears. I conclude that the discourse of ecosystem services remains a locus of ongoing contestation, which significantly complicates the relationship between what its proponents intend for it, and its ideological, institutional, and ecological consequences.