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Physical And Chemical Climate In The Nepal Himalaya, Arun Bhakta Shrestha

Doctoral Dissertations

The physical climate of the Himalaya is governed by monsoon circulation, a primary source of moisture to the region. To date, little research has focused on the physical and chemical climate in the Himalaya, while not much is known about the chemical climate there. This dissertation is a first attempt to investigate both the physical and chemical aspects of climate in the Nepal Himalaya with the objective of documenting current conditions and past trends as well as laying the foundation for investigations of their inter-relationship in the future.

Temperature and precipitation records from a network of meteorological station in Nepal …

Measuring And Modeling Northeastern Forest Ecosystem Response To Environmental Stresses, Jennifer Caroline Jenkins

Doctoral Dissertations

Because forest responses to CO$\sb2$ fertilization and associated climate change are likely to be extremely complex, numerical models representing forest response to an integrated set of future conditions can be useful predictive tools. I compared predictions of forest net primary productivity (NPP) made by two ecosystem process models (PnET-II and TEM 4.0) using different climate scenarios, spatial resolutions, and methods of representing land cover and soils. Decreasing spatial resolution did not appreciably change NPP estimates. Input datasets, particularly climate, land cover, and soil water holding capacity, were important sources of variability in NPP estimates. These datasets interacted with model structures …

Alternative Removal Methodologies For Environmental Waters, Shannon Patrick Hogan

Doctoral Dissertations

The Environmental Protection Agency (EPA) continues to establish criteria for the reduction of pathogens in environmental waters used for drinking water. The EPA also states criteria on the amount of chlorine by-products allowed in drinking water. Alternative removal methods that are used in conjunction with chlorine are needed to assure safe drinking water.

The Surface Water Treatment Rule (SWTR) states that a 99.99% reduction of viruses and a 99.9% reduction in Giardia lamblia cysts needs to be achieved by a treatment facility that uses surface water for the production of drinking water. The SWTR also states Maximum Contaminant Levels (MCL) …

Ice Core Glaciochemical Records Of Late Holocene Climatic Variability In West Antarctica, Karl Jacob Kreutz

Doctoral Dissertations

The complex atmospheric and glaciological dynamics of West Antarctica make this region of particular interest in addressing the continent's cause and effect relationship in the global climate system, and for evaluating future global change scenarios. Ice core records from this region provide the resolution necessary to both improve our understanding of modern regional climate variability, and to reconstruct past changes in a number of climate components.

High-resolution (subannual to biannual) snow and ice core samples collected from two regions of West Antarctica, Siple Dome and Marie Byrd Land, were analyzed for water soluble major ion content. Examination of detailed surface …

Controls On Ch(4) Emissions From Boreal And Arctic Wetlands, Sadredin Cyrus Moosavi

Doctoral Dissertations

This thesis examines the environmental controls on the biogeochemical cycling of the radiatively active trace gas CH$\sb4$ within boreal and arctic wetlands. Net CH$\sb4$ flux along peatland hydrologic gradients were examined to determine the effects of temperature and water table on CH$\sb4$ emissions. The level of the water table acts as a switch between CH$\sb4$ production and oxidation with small water level changes producing large changes in flux balance. Soil temperature determined whether CH$\sb4$ production potential was realized within sufficiently moist environments. A selective inhibitor technique was developed for directly measuring CH$\sb4$ oxidation in wetland soils. CH$\sb4$ oxidation was found …

Bioavailability Of Nutrients And Metals Following Land Application Of Organic Wastes, Jianqiang Zhao

Doctoral Dissertations

Field, greenhouse and laboratory studies were conducted to investigate the effects of soil-incorporated organic wastes on nitrogen release patterns, groundwater nitrate-nitrogen levels, nutrient/metal uptake, and plant yield.

Three field studies with corn (Zea mays L.) were conducted during 1993 to 1997 at three locations in New Hampshire using a randomized complete block design with three or four replications, two or three waste materials as main plots, and various application rates as subplots. Compared to dairy manure, Concord biosolids showed a slower release rate measured as soil NO$\sb3$-N concentrations in early season but higher post-harvest levels of soil NO$\sb3$-N.

Groundwater NO$\sb3$-N …

Turning To Earth: Paths To An Ecological Practice, Florence Marina Schauffler

Doctoral Dissertations

In highly developed countries like the United States, conventional approaches to environmental change emphasize systemic measures such as policies and regulations. Yet many intractable environmental problems appear to be rooted in the perspectives and practices of individual citizens. Efforts to restore 'outer ecology' may depend, therefore, on transforming 'inner ecology'--the constellation of spiritual and moral values that guide action. This dissertation examines the inner dimensions of ecological change, demonstrating how individuals redefine their relation to earth through a process of 'ecological conversion.'.

In assessing the dynamics of conversion, this work relies primarily on the testimony of six 20th-century American writers: …