The future prospects for the Lake Victoria fishery

The annual fish yields from Lake Victoria have been increasing when the species diversity was dramatically declining. The new fishery is dominated by the introduced predator (Lates niloticus Linne), the exotic herbivore (Oreochromis niloticus Linne) and an indigenous zooplanktivore (Rastrineobola argentea Pellegrin). While the three predominant fish species could sustain the high catch levels, the future viability for the fishery will depend on prudent exploitation regimes and effective management and conservation strategies.

Lake Inaha 217971

This vessel was built at Lorain, Ohio in 1919 by the American Ship Building Company. Until 1930, she was owned by the U. S. Shipping Board of Washington, D. C. That year she was sold to the Ford Motor Company. In 1943, she once again was owned by the U.S. Shipping Board. In 1946, she was purchased by the Bright Star Steamship Company of Washington, Panama. Her name was changed to "Captain John." From 1951 to 1954, she was owned by Navebras of Rio de Janeiro, Brazil. Her name was then changed to "Santa Martha." In 1954, she foundered off the coast of Brazil.

Lake Manitoba (Canada 29344)

The "Lake Manitoba" was built by Davie Shipbuilding, Ltd. in Lauzon, P. Q. in 1968. Until 1986, she was owned by Nipigon Transport, Ltd, of Montreal. That year she was purchased by Algoma Central Marine of Sault Ste. Marie, Ontario. The following year, she was renamed the "Algomarne". In 1989, she was converted to a self unloader.

Lake Belnona 217230

"Lake Belnona" was built at Saginaw, Michigan in 1918 by the Saginaw Shipbuilding Company. She was owned by the U. S. Shipping Board of Washington, D. C. until 1928 when she was scrapped at River Rouge, Michigan by the Ford Motor Company

Design investigation of the Lake Calumet Complex: improving water quality to regenerate local industrial, community, and ecosystem resources

This design thesis is an inquiry of the highly industrialized urban landscape of the Lake Calumet Complex on the South Side of the City of Chicago. It examines geologic and anthropogenic strata within this region as waste used for staging various social, industrial, and ecological systems. Today, these social, industrial, and ecological systems are not responsive to each other and certainly do not possess resilient attributes that would allow them to interact within the landscape in perpetuity. The resulting design strategy seeks to re-think the treatment of waste in the landscape into a new framework for future park design. This park will serve as grounds to interweave these complex systems in order to rehabilitate ecosystem functions and improve water quality. Additionally the park hybridizes many social and ecological functions to improve community recreational opportunities and gain public acceptance and appeal.

BALD EAGLES (HALIAEETUS LEUCOCEPHALUS) AS INDICATORS OF GREAT LAKES ECOSYSTEM HEALTH

Environmental indicators have been proposed as a means to assess ecological integrity, monitoring both chemical and biological stressors. In this study, we used nestling bald eagles as indicators to quantify direct or indirect tertiary-level contaminant exposure. The spatial and temporal trends of polychlorinated biphenyl (PCB) congeners were evaluated in nestling plasma from 1999–2014. Two hexa-chlorinated congeners, PCB-138 and 153, were detected with the highest frequency and greatest concentrations throughout Michigan. Less-chlorinated congeners such as PCB-52 and 66 however, comprised a greater percentage of total PCB concentrations in nestlings proximate to urbanized areas, such as along the shorelines of Lake Erie. Toxic equivalents were greatest in the samples collected from nestlings located on Lake Erie, followed by the other Great Lakes spatial regions. Nestling plasma samples were also used to measure concentrations of the most heavily-used group of flame retardants, brominated diphenyl ethers (BDEs), and three groups of alternative flame retardants, non-BDE Brominated Flame Retardants (NBFRS), Dechloranes, and organophosphate esters (OPs). BDE-47, 99 and 100 contributed the greatest to total BDE concentrations. Concentrations of structurally similar NBFRs found in this study and recent atmospheric studies indicate that they are largely used as replacements to previously used BDE mixtures. A variety of Dechloranes, or derivatives of Mirex and Dechlorane Plus, were measured. Although, measured at lesser concentrations, environmental behavior of these compounds may be similar to mirex and warrant future research in aquatic species. Concentrations of OPs in nestling plasma were two to three orders of magnitude greater than all other groups of flame retardants. In addition to chemical indicators, bald eagles have also been proposed as indicators to identify ecological stressors using population measures that are tied to the fitness of individuals and populations. Using mortality as a population vitality rate, vehicle collisions were found to be the main source of mortality with a greater incidence for females during white-tailed deer (Odocoileus virginianus) hunting months and spring snow-melt. Lead poisoning was the second greatest source of mortality, with sources likely due to unretrieved hunter-killed, white-tailed deer carcasses, and possibly exacerbated by density-dependent effects due to the growing population in Michigan.

APPLICATION OF AN IMPUTATION METHOD FOR GEOSPATIAL INVENTORY OF FOREST STRUCTURAL ATTRIBUTES ACROSS MULTIPLE SPATIAL SCALES IN THE LAKE STATES, U.S.A.

Credible spatial information characterizing the structure and site quality of forests is critical to sustainable forest management and planning, especially given the increasing demands and threats to forest products and services. Forest managers and planners are required to evaluate forest conditions over a broad range of scales, contingent on operational or reporting requirements. Traditionally, forest inventory estimates are generated via a design-based approach that involves generalizing sample plot measurements to characterize an unknown population across a larger area of interest. However, field plot measurements are costly and as a consequence spatial coverage is limited. Remote sensing technologies have shown remarkable success in augmenting limited sample plot data to generate stand- and landscape-level spatial predictions of forest inventory attributes. Further enhancement of forest inventory approaches that couple field measurements with cutting edge remotely sensed and geospatial datasets are essential to sustainable forest management. We evaluated a novel Random Forest based k Nearest Neighbors (RF-kNN) imputation approach to couple remote sensing and geospatial data with field inventory collected by different sampling methods to generate forest inventory information across large spatial extents. The forest inventory data collected by the FIA program of US Forest Service was integrated with optical remote sensing and other geospatial datasets to produce biomass distribution maps for a part of the Lake States and species-specific site index maps for the entire Lake State. Targeting small-area application of the state-of-art remote sensing, LiDAR (light detection and ranging) data was integrated with the field data collected by an inexpensive method, called variable plot sampling, in the Ford Forest of Michigan Tech to derive standing volume map in a cost-effective way. The outputs of the RF-kNN imputation were compared with independent validation datasets and extant map products based on different sampling and modeling strategies. The RF-kNN modeling approach was found to be very effective, especially for large-area estimation, and produced results statistically equivalent to the field observations or the estimates derived from secondary data sources. The models are useful to resource managers for operational and strategic purposes.

SYSTEM DYNAMICS MODELING AS A QUANTITATIVE-QUALITATIVE FRAMEWORK FOR SUSTAINABLE WATER RESOURCES MANAGEMENT: INSIGHTS FOR WATER QUALITY POLICY IN THE GREAT LAKES REGION

Early water resources modeling efforts were aimed mostly at representing hydrologic processes, but the need for interdisciplinary studies has led to increasing complexity and integration of environmental, social, and economic functions. The gradual shift from merely employing engineering-based simulation models to applying more holistic frameworks is an indicator of promising changes in the traditional paradigm for the application of water resources models, supporting more sustainable management decisions. This dissertation contributes to application of a quantitative-qualitative framework for sustainable water resources management using system dynamics simulation, as well as environmental systems analysis techniques to provide insights for water quality management in the Great Lakes basin. The traditional linear thinking paradigm lacks the mental and organizational framework for sustainable development trajectories, and may lead to quick-fix solutions that fail to address key drivers of water resources problems. To facilitate holistic analysis of water resources systems, systems thinking seeks to understand interactions among the subsystems. System dynamics provides a suitable framework for operationalizing systems thinking and its application to water resources problems by offering useful qualitative tools such as causal loop diagrams (CLD), stock-and-flow diagrams (SFD), and system archetypes. The approach provides a high-level quantitative-qualitative modeling framework for "big-picture" understanding of water resources systems, stakeholder participation, policy analysis, and strategic decision making. While quantitative modeling using extensive computer simulations and optimization is still very important and needed for policy screening, qualitative system dynamics models can improve understanding of general trends and the root causes of problems, and thus promote sustainable water resources decision making. Within the system dynamics framework, a growth and underinvestment (G&U) system archetype governing Lake Allegan's eutrophication problem was hypothesized to explain the system's problematic behavior and identify policy leverage points for mitigation. A system dynamics simulation model was developed to characterize the lake's recovery from its hypereutrophic state and assess a number of proposed total maximum daily load (TMDL) reduction policies, including phosphorus load reductions from point sources (PS) and non-point sources (NPS). It was shown that, for a TMDL plan to be effective, it should be considered a component of a continuous sustainability process, which considers the functionality of dynamic feedback relationships between socio-economic growth, land use change, and environmental conditions. Furthermore, a high-level simulation-optimization framework was developed to guide watershed scale BMP implementation in the Kalamazoo watershed. Agricultural BMPs should be given priority in the watershed in order to facilitate cost-efficient attainment of the Lake Allegan's TP concentration target. However, without adequate support policies, agricultural BMP implementation may adversely affect the agricultural producers. Results from a case study of the Maumee River basin show that coordinated BMP implementation across upstream and downstream watersheds can significantly improve cost efficiency of TP load abatement.

FACTORS AFFECTING DIPOREIA GROWTH RATES IN LAKE SUPERIOR

An ability to predict population dynamics of the amphipod Diporeia is important in understanding how energy pathways in the Lake Superior food web might be altered by disturbances to the ecosystem. Estimating growth rates for this prominent prey item for fish requires information on the physiological effects of changes to its environment. These effects have been investigated for Diporeia in other Great Lakes, but little is known about Lake Superior populations. The primary objective of this study is to obtain quantitative data for rates of Diporeia respiration and consumption that can be incorporated into a bioenergetics model for Lake Superior. Benthic communities in Lake Superior were sampled bimonthly from April through September during 2011 and 2012 to investigate spatial and temporal trends of Diporeia abundances as well as size class structures of the population. Additional samples of Diporeia were collected and kept alive in natural sediment for laboratory experiments. Respiration rates for Diporeia were measured by monitoring dissolved oxygen concentrations in microcosoms using microelectrodes. Additionally, a series of experiments to estimate consumption rates based on food availability were conducted using 14C-labeled algae (Selenastrum capricornutum). Amphipod population densities are highest between 30-110 m (slope) compared to 0-30 m (shelf) or >110 m (profundal) regions in Lake Superior. This heterogeneous distribution of Diporeia in Lake Superior is an important component to quantifying lake-wide biomass. Rates of oxygen consumption by Diporeia range from 32.0 to 44.7 mgO2*gDW-1*d-1, and do not vary significantly with body size per individual. The predicted consumption rate corresponding to average Lake Superior algal carbon fluxes was 0.08 ± SE mgC*gDW-1*d-1. Data on Lake Superior Diporeia biomass and bioenergetics found in this study can be incorporated in a model used to estimate the viability of this population under potential future environmental stressors.

Development of measurement and modeling techniques to quantify atmospheric deposition of persistent, bioaccumulative and toxic chemicals in the Great Lakes

Measurement and modeling techniques were developed to improve over-water gaseous air-water exchange measurements for persistent bioaccumulative and toxic chemicals (PBTs). Analytical methods were applied to atmospheric measurements of hexachlorobenzene (HCB), polychlorinated biphenyls (PCBs), and polybrominated diphenyl ethers (PBDEs). Additionally, the sampling and analytical methods are well suited to study semivolatile organic compounds (SOCs) in air with applications related to secondary organic aerosol formation, urban, and indoor air quality. A novel gas-phase cleanup method is described for use with thermal desorption methods for analysis of atmospheric SOCs using multicapillary denuders. The cleanup selectively removed hydrogen-bonding chemicals from samples, including much of the background matrix of oxidized organic compounds in ambient air, and thereby improved precision and method detection limits for nonpolar analytes. A model is presented that predicts gas collection efficiency and particle collection artifact for SOCs in multicapillary denuders using polydimethylsiloxane (PDMS) sorbent. An approach is presented to estimate the equilibrium PDMS-gas partition coefficient (Kpdms) from an Abraham solvation parameter model for any SOC. A high flow rate (300 L min-1) multicapillary denuder was designed for measurement of trace atmospheric SOCs. Overall method precision and detection limits were determined using field duplicates and compared to the conventional high-volume sampler method. The high-flow denuder is an alternative to high-volume or passive samplers when separation of gas and particle-associated SOCs upstream of a filter and short sample collection time are advantageous. A Lagrangian internal boundary layer transport exchange (IBLTE) Model is described. The model predicts the near-surface variation in several quantities with fetch in coastal, offshore flow: 1) modification in potential temperature and gas mixing ratio, 2) surface fluxes of sensible heat, water vapor, and trace gases using the NOAA COARE Bulk Algorithm and Gas Transfer Model, 3) vertical gradients in potential temperature and mixing ratio. The model was applied to interpret micrometeorological measurements of air-water exchange flux of HCB and several PCB congeners in Lake Superior. The IBLTE Model can be applied to any scalar, including water vapor, carbon dioxide, dimethyl sulfide, and other scalar quantities of interest with respect to hydrology, climate, and ecosystem science.

Biological Impacts and Uses of Black Bass Competitive Fishing Tournaments on Large Lake Systems

Thesis (Master, Biology) -- Queen's University, 2016-09-28 15:06:46.124

Turning conflict into coexistence: cross-cutting ties and institutions in the agro-pastoral borderlands of Lake Naivasha basin, Kenya

The Maasai/Kikuyu agro-pastoral borderlands of Maiella and Enoosupukia, located in the hinterlands of Lake Naivasha’s agro-industrial hub, are particularly notorious in the history of ethnicised violence in the Kenya’s Rift Valley. In October 1993, an organised assault perpetrated by hundreds of Maasai vigilantes, with the assistance of game wardens and administration police, killed more than 20 farmers of Kikuyu descent. Consequently, thousands of migrant farmers were violently evicted from Enoosupukia at the instigation of leading local politicians. Nowadays, however, intercommunity relations are surprisingly peaceful and the cooperative use of natural resources is the rule rather than the exception. There seems to be a form of reorganization. Violence seems to be contained and the local economy has since recovered. This does not mean that there is no conflict, but people seem to have the facility to solve them peacefully. How did formerly violent conflicts develop into peaceful relations? How did competition turn into cooperation, facilitating changing land use? This dissertation explores the value of cross-cutting ties and local institutions in peaceful relationships and the non-violent resolution of conflicts across previously violently contested community boundaries. It mainly relies on ethnographic data collected between 2014 and 2015. The discussion therefore builds on several theoretical approaches in anthropology and the social sciences – that is, violent conflicts, cross-cutting ties and conflicting loyalties, joking relationships, peace and nonviolence, and institutions, in order to understand shared spaces that are experiencing fairly rapid social and economic changes, and characterised by conflict and coexistence. In the researched communities, cross-cutting ties and the split allegiances associated with them result from intermarriages, land transactions, trade, and friendship. By institutions, I refer to local peace committees, an attempt to standardise an aspect of customary law, and Nyumba Kumi, a strategy of anchoring community policing at the household level. In 2010, the state “implanted” these grassroots-level institutions and conferred on them the rights to handle specific conflicts and to prevent crime. I argue that the studied groups utilise diverse networks of relationships as adaptive responses to landlessness, poverty, and socio-political dynamics at the local level. Material and non-material exchanges and transfers accompany these social and economic ties and networks. In addition to being instrumental in nurturing a cohesive social fabric, I argue that such alliances could be thought of as strategies of appropriation of resources in the frontiers – areas that are considered to have immense agricultural potential and to be conducive to economic enterprise. Consequently, these areas are continuously changed and shaped through immigration, population growth, and agricultural intensification. However, cross-cutting ties and intergroup alliances may not necessarily prevent the occurrence or escalation of conflicts. Nevertheless, disputes and conflicts, which form part of the social order in the studied area, create the opportunities for locally contextualised systems of peace and non-violence that inculcate the values of cooperation, coexistence, and restraint from violence. Although the neo-traditional institutions (local peace committees and Nyumba Kumi) face massive complexities and lack the capacity to handle serious conflicts, their application of informal constraints in dispute resolution provides room for some optimism. Notably, the formation of ties and alliances between the studied groups, and the use of local norms and values to resolve disputes, are not new phenomena – they are reminiscent of historical patterns. Their persistence, particularly in the context of Kenya, indicates a form of historical continuity, which remains rather “undisturbed” despite the prevalence of ethnicised political economies. Indeed, the formation of alliances, which are driven by mutual pursuit of commodities (livestock, rental land, and agricultural produce), markets, and diversification, tends to override other identities. While the major thrust of social science literature in East Africa has focused on the search for root causes of violence, very little has been said about the conditions and practices of cooperation and non-violent conflict resolution. In addition, situations where prior violence turned into peaceful interaction have attracted little attention, though the analysis of such transitional phases holds the promise of contributing to applicable knowledge on conflict resolution. This study is part of a larger multidisciplinary project, “Resilience in East African Landscapes” (REAL), which is a Marie Curie Actions Innovative Training Networks (ITN) project. The principal focus of this multidisciplinary project is to study past, present, and future thresholds and sustainable trajectories in human-landscape interactions in East Africa over the last millennia. While other individual projects focus on long-term ecosystem dynamics and societal interactions, my project examines human-landscape interactions in the present and the very recent past (i.e. the period in which events and processes were witnessed or can still be recalled by today’s population). The transition from conflict to coexistence and from competition to cooperative use of previously violently contested land resources is understood here as enhancing adaptation in the face of social-political, economic, environmental, and climatic changes. This dissertation is therefore a contribution to new modes of resilience in human-landscape interactions after a collapse situation.

Key Facts in Rural Health : Vulnerable Rural Counties : The Changing Rural Landscape, 2000-2010

In 2008, the U.S. experienced its worst recession since the Great Depression, particularly affecting rural America. The South Carolina Rural Health Research Center used county-level data to examine rural demographic changes over the last decade. Most counties experienced increased levels of poverty between 2000-2010. Rural counties were disproportionately affected. Rural counties experienced a growth in the 65 and older population while losing children. Rural counties gained in racial/ethnic diversity.

Best after rain : waterfall discharges and the tourist experience

Waterfalls attract tourists because they are aesthetically appealing landscape features that are not part of everyday experience. It is generally understood that falls are usually seen at their best when there is a copious flow of water, especially after heavy rain. Guidebooks often contain this observation when referring to waterfalls, sometimes warning readers that the flow may be severely reduced during dry periods. Indeed, many visitors are disappointed when they see falls at such times. Some are saddened when the discharge of a waterfall has been depleted by the abstraction of water upstream for power generation or other purposes. While, for those in search of the Sublime or merely the superlative, size is often important, small waterfalls can give great pleasure to lovers of landscape beauty. According to guidebooks, however, even these falls are usually best seen after rain. Drawing on tourist and travel literature and personal journals from the eighteenth century to the present, and with reference to examples from different parts of the world, this paper discusses the importance of discharge in the tourist experience of waterfalls.