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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Dynamic properties of sandy and gravelly soils

Menq, Farn-yuh. January 2003 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2003. / Vita. Includes bibliographical references. Available also from UMI Company.
12

Decomposition, function, and maintenance of organic matter in a sandy nursery soil

Munson, Kenneth R. January 1982 (has links)
Thesis (Ph. D.)--University of Florida, 1982. / Description based on print version record. Typescript. Vita. Includes bibliographical references (leaves 92-95).
13

A Conceptual Model of the Individual and Household Recovery Process: Examining Hurricane Sandy

Gould, Laura Ann January 2014 (has links)
This study examined how comprehensively the Bolin and Trainer (1978) model of recovery reflects the recovery process of individuals and households. A review of the literature since 1978 suggested that various revisions and additions were warranted, but additional research was needed to examine these elements collectively. Rubin and Rubin’s (2012) Responsive Interviewing Model was employed to collect and analyze data related to the recovery process of individuals impacted by Hurricane/Superstorm Sandy to determine whether an updated model was appropriate. Interviews with twenty-one respondents representing non-governmental organizations involved in Sandy-related recovery efforts revealed the need for a revised model reflecting key aspects of the original model, revisions suggested by the literature, and a new addition based on the data collected through this study. A Revised Bolin and Trainer Model of Individual and Household Recovery was suggested and implications for the discipline and practice of emergency management discussed.
14

Influence of Colorado River Silt on Some Properties of Yuma Mesa Sandy Soil

McGeorge, W. T. 01 June 1941 (has links)
This item was digitized as part of the Million Books Project led by Carnegie Mellon University and supported by grants from the National Science Foundation (NSF). Cornell University coordinated the participation of land-grant and agricultural libraries in providing historical agricultural information for the digitization project; the University of Arizona Libraries, the College of Agriculture and Life Sciences, and the Office of Arid Lands Studies collaborated in the selection and provision of material for the digitization project.
15

Interactive effects of atmospheric CO←2 enrichment, salinity and nitrogen concentration on performance of a C←3 and a C←4 strandline annual

Adams, Gina Anne January 1996 (has links)
No description available.
16

A study of adhesion between P. V. C. pipe and sand

Erickson, Forrest E. January 2011 (has links)
Digitized by Kansas Correctional Industries
17

The use of relative density for compaction control

Gerstner Bruns, Erhard January 2010 (has links)
Digitized by Kansas Correctional Industries
18

Sustainable Ecological and Recreational Management of Sandy Beach Systems

January 1994 (has links)
Sandy beaches are a primary focus of recreational and other pressures from growing coastal populations, and are major natural and economic assets for national and international tourism, but have not received adequate research attention prior to this study. Although the limited ecological research to date indicates that the nearshore volumes of sandy beach systems may be as biologically productive as estuaries and wetlands, the management of sandy beaches has not been based on ecological or sustainability principles. In this study, the principles and goals of ecologically sustainable development (ESD) are applied in investigations designed to develop improved ecological and recreational management of metropolitan sandy beach ecosystems, whereby ecological functions are maintained simultaneously with recreational and related uses. The conventional view that sandy beaches are resilient to recreational use, and are more likely to be seriously impacted by other forms of human activity, seems to have precluded serious research investigation of questions such as: what are the responses of both beach biota and human users to environmental variables influencing the system; what are the simultaneous levels, distributions and diversity of beach biota in relation to levels, distributions and categories of beach users; and what ecological impacts are likely from human beach use on biota at points of interaction, temporally and spatially? From the first section of the project, it has been shown that our present understanding of the functions, processes and responses to human disturbances of sandy beach ecosystems is extremely poor, compared with that of rock platforms. New methodologies have been developed in the current study for experimental investigations into aspects of sandy beach ecology and recreational use which have never previously been considered. Relationships between environmental variables and categories of beach use have been quantified, and show promise for use in predictive modelling to guide management. Current approaches to the management of sandy beaches and beach recreation, as aspects of environmental and coastal resource management, were then critically examined. The structures, functions and decision-making procedures of the major spheres of government, and their management agencies, were evaluated and found to provide inherent obstacles to effective ecological and recreational management of ecosystems. Coastal resource and beach management by public agencies were assessed for Durban and Sydney. Comparative analysis has provided information that can be used to develop guidelines for integrated ecologial and recreational management of sandy beach systems. In a synthesis of all of the above findings, a new procedural model has been constructed, for sustainable ecological and recreational management of sandy beach systems. This model is proposed as a framework for future integrated coastal resource research and management. Note: Three published papers have been produced from the research in this study, and have been presented at conferences, being Sinclair-Hannocks and Keane (1992) at the Sydney Sister City Environmental Summit; Sinclair-Hannocks (1993) at the World Leisure and Recreation Association Congress; and Tsang and Sinclair-Hannocks (1993) at the Local Government and Environment Conference.
19

Generation of water repellence in sands, and its amelioration by clay addition / Philip R. Ward.

Ward, Philip R. January 1993 (has links)
Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Soil Science,1993
20

Patterns and processes of sediment transport following sediment-filled dam removal in gravel bed rivers

Stewart, Gregory B. 04 May 2006 (has links)
Graduation date: 2006 / Dam removal is increasingly viewed as a river restoration tool because dams affect so many aspects of river hydrology, geomorphology, and ecology; but removal also has impacts. When a dam is removed, sediment accumulated over a dam’s lifetime may be transported downstream; and the timing, fate and consequences of this sediment remain some of the greatest unknowns associated with dam removal. In this thesis, I develop a conceptual model for erosion and deposition following removal of sediment-filled dams in mountain streams, and use field studies to document actual change. The data show that reservoir erosion in mountain rivers is likely to occur by knickpoint migration, with 85% of stored sediment being released during a single storm event in two field studies, at shear stresses less than that required for mobilization of the median surface particle size. Coarse sediment is predicted to deposit close to the dam with channel aggradation decreasing exponentially with increasing distance downstream, although some channel features are shown to have a greater propensity for aggradation than others. Field studies show that turbidity associated with dam removal and reservoir erosion may decrease hyporheic exchange, but gravel deposition (e.g., 470 m3 of gravel from Dinner Creek Dam) has the potential to more than offset that decrease, and increased hyporheic exchange is shown to reduce diurnal temperature change. Macroinvertebrate density and taxa richness did not respond to dam removal itself, but rather with time-lagged reservoir erosion. Following reservoir erosion, macroinvertebrate density recovered quickly, although longterm taxa community composition appears to be altered. On the Sandy River, field measurements of shear stress and patterns of sediment deposition following cold lahars were used as an analog to predict the fate of fine sediment, which is likely to deposit far from the dam. Results show that the Sandy River has little capacity for fine sediment storage in pools above RK 6.4 (~ 42 kilometers below Marmot Dam) at discharges associated with reservoir sediment releases. Taken as a whole, this paper illustrates a complex suite of process that may accompany removal of sediment-filled dams in mountain rivers.

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