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Numerous supraglacial and proglacial lakes have developed on debris-covered glaciers in conjunction with 20th-century retreat associated with global warming. When a glacier holds a substantial debris cover on its lower reach and/or is calving into a proglacial water body, the behaviour of its terminus can be modified to varying degrees compared to that of land-terminating or debris-free glaciers. The terminus is not just retreating from its frontal position but it is disintegrating through several processes that are linked. An improved understanding of these glacier margins is needed for the prediction and management of hazards associated with these types of lakes for hydroelectric power generation, recreational purposes and areas threatened by potential glacier outburst floods as well as for the interpretation of glacio-geological records and reconstruction of former glacial environments and palaeoclimate. The principal research question of this study is how processes of ice loss contribute to the terminus disintegration of a debris-covered, lake-calving glacier. This is addressed by an application of a field-based strategy which includes extensive field observations of variables, processes and their controls, and subsequent analysis of the data in the light of previous models and concepts. The study attempts to combine and integrate different aspects of glaciological research that have previously been examined mostly separately. It investigates the prevalent processes at the glacier terminus and their controls over different time periods ranging from days to years at Mueller, Hooker and Tasman Glaciers in Mount Cook National Park, New Zealand. The data form the basis for models of calving and pond development and future retreat scenarios. This study has demonstrated that this glacial environment is characterised by ice-frontal processes with complex inter-relationships that vary between glaciers and in particular between stages of terminus development. While surface ice melt in the terminus area is substantially reduced by supraglacial debris, sub-debris melt contributes the largest fraction of ice loss. Other important effects of debris are restraining thermal undercutting, reducing subaqueous melt and decreasing buoyancy. Data from supraglacial ponds and proglacial lakes show that limnological factors become increasingly important with increasing pond/lake size. Changes in water currents and temperature lead to changes in significance and rates of ice loss processes, the most important being the change from melting to predominantly calving. This study has confirmed the hypothesis that thermal undercutting is the rate-controlling process for calving. This process is controlled by the cliff geometry, debris supply, subaqueous geometry and water temperatures, currents and level variations. The results from the examination of calving processes suggest that the process of regular, progressive calving through the stages suggested previously may not be widely applicable to slow-moving, lake-calving glaciers. The several forms of subaerial calving identified in this study can present themselves as largely independent events, a combination of events or as a progression. At the central submerged part of the ice face, subaqueous ice melt is likely to be the dominant form of ice loss, leading to horizontal ice loss. Subaqueous calving is prevalent in gently-sloping lateral areas, leading to vertical ice loss. This process is controlled by buoyancy forces which are affected by sedimentation and lake and glacier geometry. The onset of subaqueous calving in the earlier stages of lake development is a crucial process for the transition to faster disintegration and ice loss, accelerating subaqueous melt. Due to the complex inter-relationships attempts to formulate general relationships between calving or retreat rates and other glaciological parameters may not be feasible.

(1) Aerial survey methods for estimating population size of feral water buffalo in northern Australia were examined. (2) Line transect models underestimated population size. Of six models tested the most accurate underestimated by nearly half. The models give biased estimates most probably because not all animals on the survey line were sighted . (3) Aerial strip transect surveys were also negatively biased. The extent of this bias was estimated in index-removal experiments. Experiments were carried out on two populations in areas of differing obstructive canopy cover. (4) In woodland habitat with a canopy cover of 30- 60%, a correction factor of 3.2 was required to take account of animals not seen. In forest habitat with a canopy cover of 60-100%, a correction factor of 4.9 was required. (5) Using these results, the population size of feral buffalo, cattle and horses in Kakadu National Park was estimated by aerial survey at the end of each year over 6 years. Annual rates of increase for three regions of the Park were estimated, taking into account known removals from the population. The effects of dry season rainfall and population density in the preceding year on rate of increase were examined for each species. (6) The mean annual exponential rate of increase for each species was 0.10 yr-1 for buffalo, 0.23 yr-1 for cattle and -0.14 yr-1 for horses. (7) The annual rates of increase varied greatly between years within all species and were highly correlated with dry season rainfall in the year of survey for buffalo and cattle but not for horses. (8) No significant effect of preceding density on rate of increase was found for any species. A large reduction in buffalo populations did not correspond with an increase in unharvested populations of horses, suggesting the two species do not compete for food or other resources. (9) A campaign to control populations of feral water buffalo in Kakadu National Park was assessed. Between 1979 and 1988, approximately 79,000 animals were removed, 54% by commercial live-capture, 35% by shooting from helicopters and 10% by shooting from the ground. (10) In the period 1983-1988 when population estimates from aerial survey are available, mean buffalo population density was reduced from 5.60 km-2 to 1.17 km-2 over the surveyed area of the Park. (11) The costs of removal by shooting from helicopters, capturing animals alive and shooting from the ground were compared. The mean costs per animal in 1988 were $24.13, $74.53, and $86.02 respectively. (12) The effects of initial density and time spent shooting on number of animals removed by shooting from helicopters were examined. One linear and two curvilinear models were fitted to data from four different removal exercises. The relationship between time spent shooting and number removed was best described by a curvilinear (Ivlev) function. This model was used to estimate costs of control to a specified density. (13) Model regression coefficients differed between removal exercises, suggesting that the number removed may be affected by variables other than time spent shooting and initial density. Data from the range of conditions encountered during removal is thus likely to be required for robust estimation of removal costs.

This study considers how environmental concerns helped shape Melbourne's public parkland in the period 1850-1920, when Melbourne's first parks were developed and during which ecology began to replace natural history as the determinant of environmental thought. Theories propounded by such figures as Alexander von Humboldt and George Perkins Marsh profoundly influenced land management around the world during this period, and by relating specific parkland developments to professional and popular ideas about the environment the study aims to place the parkland in an international context. Previous research has given little thought to the effect of environmental thought on Melbourne's parks, except for Ferdinand von Mueller's development of the Melbourne Botanic Garden where the influence is evident. Such influence has not been considered in Clement Hodgkinson's contemporaneous development of the city's other parks and gardens even though, like Mueller, Hodgkinson was closely involved with environmental issues of the day. The Field Naturalists Club of Victoria, of which Mueller was a member, has long been credited with influencing Wattle Park's development early in the 20th century, although there is little critical analysis of the extent to which it was able to bring popular concerns about the environment to bear on park design. The relationship between Mueller's environmental views and actions and his development of the Botanic Garden is discussed first. Connections are then made between Hodgkinson's early experiences as a surveyor, his later work as Victoria's foremost land manager, his association with Mueller, and his design of Melbourne's first parks and gardens. Finally, the FNCV's involvement in park development is examined while exploring the changing nature of environmental thought. Clearly, environmental thought did influence the development of some parkland, but only those reserves administered by Mueller and Hodgkinson and only while the two men remained in control. The success of the FNCV in influencing the future direction of any Melbourne park or garden is not so easily discernible, with little evidence that the Club played an important role in Wattle Park's development.

Thesis (D.Admin.(Public Administration))--University of Pretoria, 2007. / Summary and abstract in English. Includes bibliographical references. Available on the Internet via the World Wide Web.

Thesis (M.S.) in Forestry--University of Maine, 2004. / Includes vita. Includes bibliographical references (leaves 104-115).

<p>Syftet med uppsatsen är att öka förståelsen dels för hur olika brukargruppers samutnyttjande av offentliga platser fungerar och dels för hur detta hanteras inom planeringen. Använda teorier behandlar det offentliga rummets demokratiska funktion och brukares upplevelse av det. En kvalitativ metod har använts där observationer och intervjuer med brukare i Trekantsparken och planerare samt planeringsdokument från Stockholms stad har varit grunden för empirin, en kvalitativ analys har sedan utförts. I parken förekommer intressemotsättningar mellan de brukare som leker med sina barn i parken eller bor i den nya bebyggelsen och de som dricker alkohol. Man kan också notera en uppdelning av användandet. Fokus i planerarnas hantering av dessa ligger på trygghet och vad människor värderar i sin vardag. Åtgärder som vidtas är att informera om ansvarsförhållanden och genomföra trygghetsvandringar. Man talar om att genomföra en tredje insats som går ut på att bryta en av de fysiska uppdelningarna av parken. Det framkommer även att det finns motsättningar mellan de olika syften med det offentliga rummet som uttrycks inom olika nivåer inom planeringen.</p>

<p>Electricity accounts for much of the primary energy used in China, and more thanthree-quarter of the total electricity is generated by coal combustion. Coal burningcombined with flue gas cleaning system generates large quantity of coal combustionproducts (CCPs), which has caused significant environmental and economic burden tothe economy, ecology and society. Of great importance are thus different applicationswhich contribute to the increased use of CCPs. This thesis looks at an overview ofCCPs production and utilization all around the world and investigates current CCPsapplications as well as potential technically sound and economically justifiedtechnologies. Results of this thesis show that CCPs utilization rate in differentcountries varies widely from 13% to 97%. Worldwide, a significant proportion ofCCPs from the main producers, e.g. China, the United States and India, is still beingdisposed off, resulting in a low-level of overall utilization of these products. It isevident that the amount of CCPs produced substantially exceeds consumptionsbecause of various existing obstacles and limitations. In order to formulate effectiveapproaches, identifying challenges to increased use of CCPs is of great weight. The aimof this thesis is to analyze current and potential utilizations of CCPs and morespecifically address factors that inhibit or promote the use of CCPs from coal-firedpower plants in China.</p><p>Savings of natural resources, energy, emissions of pollutants, GHG emissions anduseful land were found as the major incentives for CCPs utilization. In China, a ban ofsolid clay bricks was also found to be a very powerful measure to stimulate thedevelopment of other by-product based wall materials while saving useful land andprotecting the environment. However, this strong support from the government hasnot been fully implemented, which seriously hampered CCPs uses. Results presentedin this thesis also show that high transportation cost of low unit-value CCPs,competition from available natural materials and spatial variation in supply-demandposes three of the most important barriers to the increased use of CCPs in China.Industrial organizations with assistances from the government have shown to be offundamental importance for formulating approaches to take in overcoming thebarriers.</p><p>This thesis emphasized that transforming laboratory- and pilot-scale technologies intocommercial productivity is of the highest priority for increased use of CCPs. Aconceptual model of CCPs Eco-Industry Park (EIP) as a potential effective solutionwas proposed. Mutual economic and environmental benefits can be achieved throughthe collaboration between different industries in the CCPs EIP. And other feasiblerecommendations of initiatives from both the government and industries were alsodiscussed.</p>

Ambystoma macrodactylum (long-toed salamander) and A. gracile (northwestern salamander) are two common salamander species occupying key trophic positions in mountain ponds of Mount Rainier National Park. The objective of this research was to document and evaluate the distributions and abundances of the two species, relative to habitat characteristics of ponds in the park. Amphibian distributions and abundances were assessed in 20 ponds from June through September 1993 to 1996. Nutrient concentrations (total nitrogen, Kjeldahl-N, total phosphorus, and orthophosphate-P), habitat characteristics (surface area, depth, elevation, substratum organic content lost on ignition, amount of coarse woody debris, aquatic vegetation, and bottom firmness), and water quality (temperature, dissolved oxygen, alkalinity, conductivity, and pH) were measured. Distinct habitat associations were found for each Ambystoma species. Ponds with one species only were different in surface area, maximum depth, substratum organic content, and elevation. Ponds with A. macrodactylum were small, shallow, high in elevation, and had firm sediments low in organic matter relative to A. gracile ponds. Ambystoma macrodactylum ponds typically contained little coarse woody debris relative to the amount of aquatic vegetation. Ambystoma gracile ponds were large, deep, low in elevation, had flocculent sediment high in organic content, abundant coarse woody debris, and little aquatic vegetation relative to A. macrodactylum ponds. Two ponds supported reproducing populations of both species and exhibited habitat characteristics intermediate to the allopatric pond types. These findings suggest that habitat complexity plays an important role in the segregation of A. macrodactylum and A. gracile. / Graduation date: 2000

Thesis (M.A.)--Ohio University, June, 2006. / Title from PDF t.p. Includes bibliographical references (p. 85-96)