Rivers deliver significant macronutrients and sediments to lakes that can vary substantially throughout the year. These nutrient and sediment loadings, exacerbated by winter and spring runoff, impact aquatic ecosystem productivity and drive the formation of harmful algae blooms. The source, extent and magnitude of nutrient and sediment loading can vary drastically due to extreme weather events and hydrologic processes, such as snowmelt or high flow storm events, that dominate during a particular time period, making the temporal component (i.e., time over which the loading is estimated) critical for accurate forecasts. In this work, we developed a data-driven framework that leverages the temporal variability embedded in these complex hydrologic regimes to improve loading estimates. Identifying the "correct" time scale is an important first step for providing accurate estimates of seasonal nutrient and sediment loadings. We use water quality concentration and associated 15-minute discharge data from nine watersheds in Vermont's Lake Champlain Basin to test our proposed framework. Optimal time periods were selected using a hierarchical cluster analysis that uses the slope and intercept coefficients from individual load-discharge regressions to derive improved linear models. These optimized linear models were used to improve estimates of annual and "spring" loadings for total phosphorus, dissolved phosphorus, total nitrogen, and total suspended loads for each of the nine study watersheds. The optimized annual regression model performed ~20% better on average than traditional annual regression models in terms of Nash-Sutcliffe efficiency, and resulted in ~50% higher cumulative load estimates with the largest difference occurring in the "spring". In addition, the largest nutrient and sediment loadings occurred during the "spring" unit of time and were typically more than 40% of the total annual estimated load in a given year. The framework developed here is robust and may be used to analyze other units of time associated with hydrologic regimes of interest provided adequate water quality data exist. This, in turn, may be used to create more targeted and cost-effective management strategies for improved aquatic health in rivers and lakes.

Silviculture practices interact with multiple sources of variability to influence regeneration trends in northern hardwood forests. There is uncertainty whether low-intensity selection harvesting techniques will result in desirable tree regeneration. Our research is part of a long-term study that tests the hypothesis that a silvicultural approach called "structural complexity enhancement" (SCE) can promote accelerated development of late-successional forest structure and functions. Our objective is to understand the regeneration dynamics following three uneven-aged forestry treatments modified to increase postharvest structural retention: single-tree selection, group selection, and SCE. In terms of regeneration densities and composition, how do light availability, competition, seedbad, and herbivory interact with overstory treatment effects? To explore these relationships, manipulations and controls were replicated across 2-hectare treatment units at two sites in Vermont, USA. Forest inventory data were collected pre-harvest and 13 years post-harvest. We used linear mixed effects models with repeated measures to evaluate the effects of treatment on seedling and sapling abundances and diversity (Shannon-Weiner H'). Multivariate analyses evaluated the relative predictive strength of treatment versus alternative sources of ecological variability. Thirteen-years post-harvest, the harvested treatments were all successful in recruiting a sapling class with a significantly higher mean than the control. However, in all of the treatments prolific beech regeneration dominated the understory in patches. Seedling densities exhibited pulses of recruitment and mortality with a significant positive treatment effect on all harvested treatments in the first four years post-harvest. Seedling diversity was maintained, while sapling diversity was negatively influenced by herbivory (deer and moose browse) and leaf litter substrate. Multivariate analyses suggest that while treatment had a dominant effect, other factors were strongly influential in driving regeneration responses. Results indicate variants of uneven-aged systems that retain or enhance stand structural complexity, including old-growth characteristics, generally regenerate at adequate and desirable densities depending on site conditions.

Student Number : 0500819P - MSc dissertation - School of Geography, Archaeology and Environment Studies - Faculty of Science / The research assesses the impacts of Community-Based Natural Resource Management (CBNRM) and tourism upon community livelihoods, local behaviour and wildlife conservation. The research aims to analyze whether CBNRM is working as it is intended as well as to assess the socio-economic status of the community in terms of whether the CBNRM project has influenced their livelihoods for the better, than when the project was non-existent. The research findings indicate that CBNRM projects can deliver in terms of improvement of rural local community’s livelihoods and natural resources management. However, a lack of understanding of the CBNRM concept, lack of entrepreneurships and managerial skills, poor participation by general membership, poor distribution of the income benefits and lack of consultation to the project’s community membership by the project management are some of the constraints and challenges that emerge from the case study of the Nata Bird Sanctuary CBNRM project.

This study examines the process and implementation of a conservation project in Chimanimani locality, a remote rural area located in Sussundenga district in the central province of Manica. The Chimanimani Transfrontier Conservation Area Project, as the Project became known, was one of the conservation area projects established in three provinces of Mozambique (Maputo, Gaza and Manica1) in the years following the civil conflict. In essence the Chimanimani Project was framed to enhance environmental sustainability of the targeted areas and contribute to poverty reduction through sustainable use of local natural resources. Accordingly, it was seen as a way of improving the overall quality of life of the targeted communities. The study analyses the Project efforts of utilizing the synergies between conservation and community development in rural areas where income-earning opportunities are limited. The research has focused on two of the five Chimanimani communities (Nhaedzi and Moribane) and brings to the fore evidences of the factors that have affected either positively or negatively the success of the Project.

This dissertation examines the relationship between political institutions and development policies across a wide array of policy arenas. It consists of three essays. In the first essay, I examine how corruption in political institutions affects citizens’ attitudes towards proposed policy reforms that should yield long-run benefits. I argue that where corruption in political institutions reduces citizens’ benefits from existing programs, governmental promises to deliver benefits via reforms are less credible. Thus, citizens will cling to inefficient policies not because they are unable to recognize the benefits of reform but because they do not trust political institutions to implement reforms in ways that will benefit them in practice. I use this logic to explain why citizens frequently resist attempts to reform the economically and environmentally costly practice of setting domestic gasoline prices below market prices. To reveal these patterns, I rely on original survey and administrative data from Indonesia. The second essay maintains the focuses on the quality of political institutions and natural resource governance but from a more macro perspective. In this essay, I argue that political regimes and political time horizons shape financial arrangements between governments and multinational oil companies. This essentially asks the reverse of a central question in comparative politics. Rather than asking how oil income affects political institutions, I ask how political institutions motivate politicians to make policy choices that increase or decrease the government’s access to oil income over time. To do so, I utilize an original dataset on financial arrangements between host countries and multinational oil companies, as reflected in historically confidential oil contracts. The final essay travels to a different substantive area of development policy, yet allows for a critical role for political institutions. This essay argues that the relationship between developing country governments and foreign aid donors should be conditional on the quality of political institutions, with aid donors giving countries with institutions better able to commit to selecting policies that promote development wider latitude to direct foreign aid resources towards local priorities. Instead, I find that political and security alliances shape whether donors give developing country governments more “ownership” over aid flows. Overall, the dissertation deepens understanding of the relationship between the quality of political institutions and policies within developing countries, while offering insights into contemporary policy debates about natural resource governance, environmental politics, and development aid.

The sustainable management of the environment has emerged as a major conceptual and policy challenge. In this thesis, I discuss both general theoretical considerations and aspects of a striking and important case study. In chapters 1-4, I study the dynamics of collective decisions on long-term investments in public goods, in situations in which different stake-holders disagree on the relative valuation of short-term costs and future benefits. The discussion is inspired by climate change economics but is general. Chapters 5-8 discuss aspects of the depletion of groundwater in India, one of the most dramatic resource sustainability crisis in the world, and analyze empirically the implications for irrigation, in terms of sustainability, efficiency and reliability.

Shoreline hardening and construction of restoration oyster reefs are occurring at rapid rates throughout Chesapeake Bay and little research has been conducted to determine whether installment of a hardened shoreline and oyster reef placement has an effect on the surrounding benthic infaunal communities. I investigated the effects of shoreline development and oyster reefs on benthic communities in Lynnhaven, Virginia. Throughout Lynnhaven, I determined the effects of shoreline type (natural marsh, oyster reef, rip-rap and bulkhead), sediment grain size, Total Organic Carbon/Total Nitrogen (TOC/TN) of the sediment, and predation (caging study) on density, biomass, and diversity of benthic infauna. An information-theoretic approach using Akaike’s Information Criterion (AIC) was used. Of the variables measured, shoreline type was the best predictor of benthic infaunal density (highest density at oyster reefs and lowest at bulkheads), while sediment composition (grain size and TOC/TN) and predators were the best predictors of biomass and diversity. Lynnhaven is a polyhaline, shallow, semienclosed, natural marsh-dominated system with high overall productivity, which could be masking any small-scale disturbances due to shoreline hardening at the sites. A Before-After-Control-Impact (BACI) study was completed at two sites (Eastern Branch and Linkhorn Bay) in Lynnhaven to examine the benthos before and after placement of oyster reefs. Replicate samples for benthic infauna, sediment grain size, and sediment TOC/TN were taken before and one year after reef placement. Based on the AIC analysis, oyster reefs had a positive effect on infaunal density at the Linkhorn Bay site after one year, mainly attributed to an influx of the bivalve Gemma gemma. The density increase occurred even with a decrease in polychaete density. There was no change in infaunal biomass or diversity at this site. At the Eastern Branch site, there was no effect of oyster reefs on density, biomass, or diversity. To characterize the benthos prior to reef placement, benthic samples were collected at two sites (Eastern Branch and Linkhorn Bay) in Lynnhaven. Four reef types (oyster shell, rip-rap, concrete modules, and reef ball) were deployed at both sites. Oyster production values for existing oyster reefs were used to estimate expected oyster production on each reef type. Biomass estimates and published P:B ratios for each taxa were used to calculate secondary production for benthic infauna and oysters. Lost benthic production due to each reef type at both sites was compared to estimated oyster production on each reef type to determine if each reef compensated for benthic production lost by placing the reefs on top of the benthos. Oyster production on oyster shell and reef ball reefs compensated for benthic production lost due to placement of the reefs at both sites. Oyster productivity on rip-rap and concrete module reefs did not compensate for lost benthic production at the highly productive Eastern Branch site, and barely compensated for lost benthos at the lower productivity Linkhorn Bay site. The preservation of natural marsh and use of the proper types of oyster reefs could help maintain the high productivity of both the benthic community and the Lynnhaven system itself.

The International Organization of Standardization (ISO) has created a series of voluntary standards (ISO 14000) which promote waste reduction and improve businesses’ environmental management. ISO 14001 is the Environmental Management System portion of ISO 14000 requiring employee awareness and involvement. The Robert Bosch Corporation is undergoing ISO 14001 certification. In this study, a 23-question survey was used to evaluate Bosch employees’ awareness of ISO 14000 and their support of a waste reduction program at four plants (Johnson City, TN; Sumter, South Carolina; Ashland, Ohio; and South Bend, Indiana). Employees surveyed were not yet familiar with ISO 14000 and that their awareness varied across job title and location. Employees were pro-environment and supported waste reduction programs under the condition they would not be penalized financially as a result. Results of this study will be used to identify strengths and weaknesses in EMS training at the surveyed facilities.

Bison spp. (bison) fossils are scarce on the Colorado Plateau, especially within the greater Grand Canyon region. Because of the poor fossil record for bison on the plateau and in Grand Canyon National Park, various resource managers have surreptitiously designated bison a nonnative and human-introduced species. The lack of evidence for bison seems to be the result of collection bias rather than a true lack of bison remains. Today, Grand Canyon National Park has a neighboring herd of 350 bison that have meandered unwantedly onto National Park lands from neighboring Forest Service and State of Arizona lands. This study spatiotemporally illustrates bison are recently native to the greater Grand Canyon area based on previously misidentified specimens in archaeological collections. Data here may require resource managers to reconsider whether or not bison should be reconsidered a native species to the Grand Canyon National Park and elsewhere on the Colorado Plateau.

The research projects presented in this dissertation used multiple tagging technologies to examine the movements, growth, and mortality rates of summer flounder tagged and released in Chesapeake Bay. In the first two chapters, I used acoustic, archival, and conventional tags to examine the behavior of summer flounder on different spatial scales. Investigating the movement behavior of individuals on different scales is an important step towards understanding how large-scale distributions of a population are established. Based on the observed behaviors of summer flounder, I hypothesize that the movements of these fish are primarily related to foraging behavior while they are resident in Chesapeake Bay. In the third chapter, I use growth models to investigate hypotheses regarding recreational angler noncompliance with minimum size regulations in Virginia. Angler noncompliance with management regulations can severely degrade the ability of fishery managers to prevent overexploitation of fish populations. Using a growth model fit to recreational angler mark-recapture data, I demonstrate that recreational anglers in Virginia responded to changes in summer flounder management regulations, but considerable levels of noncompliance were detected in years when management agencies drastically increased the minimum size regulations. In the final chapter, I attempt to estimate natural and fishing mortality rates of summer flounder using conventional mark-recapture data collected by an angler tagging program. These mortality rates were estimated using a Barker model, which is a generalization of the Cormack-Jolly-Seber tagging model. Results from this study indicated that sublegal summer flounder experience different emigration or mortality processes than do larger fish. Furthermore, handling and tagging mortality rates of summer flounder were much larger than the recreational discard mortality rate currently used in the stock assessment, implying that the recreational discard mortality rate should be reexamined. The research presented in this dissertation provides information that could be used by management agencies to further understand the behavior of summer flounder, and how to most effectively manage this population.