Atlanta is one of the largest metropolitan areas in the southeastern United States and is the only area in the region currently listed in “serious” 1-hour ozone nonattainment. Despite its exceedance history, impacts on Atlanta’s urban forests have not been the focus of any major studies. The purpose of this study was to examine air pollution damage to vegetation using a foliar-injury survey on Stone Mountain. The objectives of this project included 1) establishing that pollution transport from Atlanta to Stone Mountain occurs, 2) determining the magnitude of ozone concentrations near Stone Mountain and 3) assessing sensitive plant species on Stone Mountain for foliar injury. Results from this study confirm that Stone Mountain is located downwind from Atlanta. Ozone concentrations were sufficiently high to damage vegetation and these consistently peaked in July. Foliar injury was present on understory species on Stone Mountain, but was not observed on loblolly pine species.

Tyrimo objektas – Pagramančio regioninio parko bebrų populiacija. Pagrindinis tyrimų vienetas – bebravietė. Tyrimo tikslas – ištirti bebrų pasiskirstymą atskiruose biotopuose ir įvertinti jų įtaką aplinkai. Tikslui įgyvendinti buvo iškelti uždaviniai: Nustatyti bebrų gausą atskiruose biotopuose ir įvertinti jų įtaką aplinkai Nustatyti bebrų pasiskirstymą Tyrimų metodai: literatūros loginės analizės, tiesioginis bebrų stebėjimas, jų veklos žymių analizės. Buvo naudojami tokie tyrimo duomenys: kartografinė medžiaga, bebrų apskaita, bebrų poveikio aplinkai vertinimas. Mokslinis tiriamasis darbas buvo atliktas 2007 metų pavasarį, nutirpus sniegui ir susinormalizavus vandens lygiui (balandžio mėnesį). Pirminiai duomenys apie bebraviečių lokalizacijas buvo renkami pasitelkiant miškininkų, medžiotojų pateiktą informaciją. Ši informacija buvo tikrinama natūroje bei ieškomos naujos nežinomos bebravietės. Kiekviena bebravietė esanti tiriamoje teritorijoje buvo užregistruota. Rezultatai: Nustatyta, kad Pagramančio regioniniame parke daugiausia bebrai įsukuria miškuose ( 53 % ), melioracijos kanaluose ( 70,6 % ) ir sudaro mažas šeimas ( 35 % ). Šioje teritorijoje daugiausia jaunų ar vidutinio amžiaus bebraviečių, pilnos sudėties šeimų ( 58,8 % ). Pagal patvankos pobūdį teritorijoje visos bebravietės buvo su užtvankom, kadangi ežerų čia nėra, o bebrai gyvena tik melioracijos kanaluose ir upėse. / The subject of reserach – beavers population in Pagramantis regional park. The main fugure – beavers lodge. The point of reserach – to analyse beavers distriction in the separate ecosystems and set their effect to landscape. To implement the main point I set a tasks: To set plenty of beavers in different ecosystems and set their effect to landscape. To set distribution of beaver. The method of reserch. Logical analysis of literature, ostensible observation of beaver, wheir work signs analysis. Where were usable material of research: cartografic material, record of beaver, their effect to landscape. Scientific research project was made in 2007 spring, when snow was numbed and water level was normalized ( in April ). Incomposite data about localization of lodge was elected by invoking information of foresters and hunters. This information were cheking in nature and where were seeking new and undiscovered lodge of beavers. Each of lodge in searching teritory were registered. Results: Finding that in Pagramantis regional park beavers settle down in forests ( 53 % ), in melioration channels ( 70,6 % ) and beavers making a small familys ( 35 % ). In this territory for the most part are young and middle-aged lodges, full compositios of family ( 58,8 % ). By the tone of lift in territory all the lodges were with dams, whereas where no lakes beavers are living in melioration channles and rivers.

Freshwater ecosystem degradation in the Amazon and Orinoco river basins is increasing due to rising human population numbers, and large water development projects. Therefore, monitoring ecosystem condition in these rivers of high biodiversity is of global conservation importance. This dissertation evaluated the potential of using river dolphins as indicators of ecosystem condition in large tropical rivers of South America. First, population estimates of river dolphins were obtained by line-strip transect surveys and mark-recapture methods on photo-identifications. Using this information, I identified critical habitat, hotspots, and areas of concern for river dolphins, as well as the relationship between dolphin density and group size estimates with ecological features. Second, I evaluated the relationship between dolphin estimates and human stressors. Higher densities of dolphins occurred in rivers with low indices of overall freshwater degradation, such as rivers with high water quality and the lowest human population numbers. Thus, dolphin density estimates seem to be good indicators of freshwater ecosystem degradation in the Amazon and Orinoco basins. These top predators not only are indicator species, but also have the potential to act as flagship and sentinel species, indicating freshwater ecosystem degradation and stimulating conservation action. This dissertation highlights the large changes in the Amazon and Orinoco that are approaching fast. Indicator, flagship and sentinel species can become science-based conservation tools not to only document freshwater ecosystem degradation, but to raise awareness about broader implications of human stressors on biodiversity and river systems.

The motivation for this study arose from the dual observation that there are very few estimates of the local costs of climate change in developing countries and that the few studies that do exist rarely take into account the non-market value of ecosystem services. Using a case study of a coastal lagoon ecosystem in Uruguay, I explore practical reasons for why this might be the case. Informational difficulties related to identifying local climate trends and the identification of ecosystem services as well as the relevance and feasibility of monetary valuation methodologies are discussed using specific examples. Three valuation methodologies are implemented to estimate the monetary values of climate change impacts on specific ecosystem services. The results suggest that climate change is affecting the economic value of the coastal lagoon ecosystem. Implications for local management and lessons learned from the case study are discussed.

The i-Tree Eco model, developed by the U.S. Forest Service, is commonly used to estimate the value of the urban forest and the ecosystem services trees provide. The model relies on field-based measurements to estimate ecosystem service values. However, the methods for collecting the field data required for the model can be extensive and costly for large areas, and data collection can thus be a barrier to implementing the model for many cities. This study investigated the use of geospatial technologies as a means to collect urban forest structure measurements within the City of Ottawa, Ontario. Results show that geospatial data collection methods can serve as a proxy for urban forest structure parameters required by i-Tree Eco. Valuations using the geospatial approach are shown to be less accurate than those developed from field-based data, but significantly less expensive. Planners must weigh the limitations of either approach when planning assessment projects.

Oyster reef habitats have declined from historic levels due to a variety of reasons, including overharvest, disease, and degraded water quality. The harvesting of oysters has led to a loss of reef habitat for both oysters and reef-associated fauna. When oysters spawn, the larval oysters, or spat, depend on hard substrate for settlement and growth. Oyster shell is the preferred substrate for use in restoration because it most closely matches natural reef habitat, but it is often expensive and in limited supply. This study incorporated field and laboratory experiments to assess the relative habitat value of alternative substrates (crushed concrete, porcelain, crushed limestone, and river rock, as well as oyster shell) for larval oyster recruitment as well as reef resident fishes and macro-invertebrates. Replicate trays of each substrate type were deployed in St. Charles Bay, TX for four months during spring and summer 2012 and assessed for oyster recruitment and faunal diversity and density. Concrete, river rock, limestone and porcelain had similar spat recruitment densities compared to oyster shell (1300-2300 spat). Spat shell heights were also larger on these substrates (13-16 mm), while spat on porcelain substrates were slightly smaller (10-13 mm). All substrates except bare sediment had similar fauna species densities (200-500 individuals m-2). Limestone had lower fauna diversity (H’; 0-1) than concrete and shell (1-2). Laboratory experiments compared the effectiveness of these substrates in providing prey refuge from pinfish and blue crab predators. All substrates performed similarly resulting in very low (<20 %) prey mortality rates for either predator. Results may enable future restoration plans to be implemented at a lower cost while providing similar habitat functions.

Freshwater ecosystems face unprecedented levels of human-induced stresses and it is expected that the invasion of non-indigenous species will cause the greatest loss of biodiversity in lakes and rivers worldwide. Bythotrephes longimanus is a predatory invertebrate that invaded North America in the early 1980s, first being detected in the Great Lakes, and then moving to a number of inland lakes in Ontario and the northern United States. Using experimental and survey-based approaches, I tested several hypotheses concerning the effects of Bythotrephes on native zooplankton community structure and function. My results indicate that Bythotrephes reduces total abundance, biomass, and richness of zooplankton, especially cladoceran taxa, throughout the ice-free season. As a result of high predation pressure by the invader, total seasonal and epilimnetic zooplankton production was also substantially reduced in invaded lakes, which may have important consequences for the transfer of energy to fish and other taxa that feed on zooplankton. Interestingly, there was some evidence that zooplankton shifted their reproduction in time and space to avoid Bythotrephes, which may buffer the effects of the invader on food web functioning. Other measures of ecosystem function were relatively unaffected by the invasion of Bythotrephes. In addition, Bythotrephes may interact in unexpected ways with other anthropogenic stressors, and act to slow down the process of recovery by preying on species that maintain community abundance during acidification, but also affecting species attempting to recolonize historically acidified lakes. Although dispersal of zooplankton may maintain some of the ecosystem functions provided by zooplankton communities, loss of biodiversity may be a permanent result of invasion. The effects of the continued spread of invasive species across the landscape may be profound, as the invader Bythotrephes has demonstrably altered zooplankton communities and may reduce the ability of freshwater ecosystems to respond to future environmental change and maintain ecosystem functioning. / Thesis (Ph.D, Biology) -- Queen's University, 2007-07-19 14:56:57.102

Cape Bounty, Melville Island is a partially vegetated High Arctic landscape with three main plant communities: polar semi-desert (47% of the study area), mesic tundra (31%) , and wet sedge meadows (7%). The objective of this research was to relate biophysical measurements of soil, vegetation, and CO2 exchange rates in each vegetation type to high resolution satellite data from IKONOS-2, extending plot level measurements to a landscape scale. Field data was collected through six weeks of the 2008 growing season. Two IKONOS images were acquired, one on July 4th and the other on August 2nd. Two products were generated from the satellite data: a land-cover classification and the Normalized Difference Vegetation Index (NDVI). The three vegetation types were found to have distinct soil and vegetation characteristics. Only the wet sedge meadows were a net sink for CO2; soil respiration tended to exceed photosynthesis in the sparsely vegetated mesic tundra and polar semi-desert. Scaling up the plot measurements by vegetation type area suggested that Cape Bounty was a small net carbon source (0.34 ± 0.47 g C m-2 day-1) in the summer of 2008. NDVI was strongly correlated with percent vegetation cover, vegetation volume, soil moisture, and moderately with soil nitrogen, biomass, and leaf area index (LAI). Photosynthesis and respiration of CO2 both positively correlated with NDVI, most strongly when averaged over the season. NDVI increased over time in every vegetation type, but this change was not reflected in any significant measured changes in vegetation or CO2 flux rates. A simple spatial model was developed to estimate Net Ecosystem Exchange (NEE) at every pixel on the satellite images based on NDVI, temperature and incoming solar radiation. It was found that the rate of photosynthesis per unit NDVI was higher early in the growing season. The model estimated a mean flux to the atmosphere of 0.21 g C m-2 day-1 at the time of image acquisition on July 4th, and -0.07 g C m-2 day-1 (a net C sink) on August 2nd. The greatest uncertainty in the relationship between NDVI and CO2 flux was associated with the polar semi-desert class. / Thesis (Master, Geography) -- Queen's University, 2011-12-28 23:27:34.824

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