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Status Of Heavy Metals Pollution In The Nile Around Khartoum Area, F I. Habbani, S E. Salih Dec 1999

Status Of Heavy Metals Pollution In The Nile Around Khartoum Area, F I. Habbani, S E. Salih

Tanzania Journal of Science

Investigations for heavy metals pollution in the Nile around Khartoum area were carried Out using the technique of x-ray fluorescence (XRF). Samples were collected from various locations around Khartoum area before and after the flood. The results indicated that there was no heavy metals pollution in the Nile in Khartoum area resulting from industrial activities. The origin for the observed heavy metals concentrations, except for Pb, was considered to be soil erosion caused by the river on its journey from the Ethiopian Highlands and Lake Victoria. However, there are indications that some Pb pollution could be due to emissions of …


Breeding Bird Census On Four Shelterwood-Cut Stands In Buckingham County, Virginia, Sally Ann Statham Dec 1999

Breeding Bird Census On Four Shelterwood-Cut Stands In Buckingham County, Virginia, Sally Ann Statham

Theses & Honors Papers

The Breeding Bird Census (BBC) technique was used to study breeding bird populations on two paired shelter wood-cut oak stands in Buckingham County, Virginia. The four plots are part of a study to determine oak regeneration following controlled burns in the Virginia piedmont. There is an interest in determining how shelter wood-cut plots affect the breeding birds of Virginia. A total of twenty-seven bird species established and defended territories among the four plots. Ten bird species defended territories on all four plots. All of these species were birds characteristic of forest habitats.


Fisheries Research Report No. 118 - A Study Into Western Australia's Open Access And Wetline Fisheries, F Crowe, W Lehre, R C J Lenanton Dec 1999

Fisheries Research Report No. 118 - A Study Into Western Australia's Open Access And Wetline Fisheries, F Crowe, W Lehre, R C J Lenanton

Fisheries Research Reports

Western Australia's wetline fishery potentially includes every licensed fishing boat in the State and encompasses a number of inter-relationships between various boats and commercial fisheries. This study covers the 'wetline' or open access fishery, which encompasses those activities associated with the unrestricted Western Australian fishing boat licence (FBL). The activities associated with this fishery involve any commercial fishing which is not covered by fisheries legislation.

A separate section entitled 'So you want to go wetlining?' is provided at page 101 as an easy reference guide to industry and others interested in wetline fishing. It is recommended that it be read …


Investigating Ground And Surface Water In The Republican River Basin Of Nebraska Using Water Chemistry And Environmental Isotopes, Jennifer J. Schellpeper Dec 1999

Investigating Ground And Surface Water In The Republican River Basin Of Nebraska Using Water Chemistry And Environmental Isotopes, Jennifer J. Schellpeper

School of Natural Resources: Dissertations, Theses, and Student Research

Recent legal battles concerning water use initiated an investigation of the stream/aquifer relationships in the Republican River Basin located in southwest Nebraska. Ground and surface water was analyzed for tritium, deuterium, 18O, and major ions. Temperature, pH, conductivity and alkalinity were determined on-site. Samples were collected during 1997 and 1998 from irrigation wells throughout the entire basin. Localized interactions between groundwater and surface water were examined during twenty-four hour pump tests performed on the irrigation wells screened in the alluvium along the river valley and its tributaries. These data show there are differences between the ground and surface waters …


Ecology Of Elk In Northwestern Nebraska: Demographics, Effects Of Human Disturbance, And Characteristics Of Calving Habitat, Bruce A. Stillings Dec 1999

Ecology Of Elk In Northwestern Nebraska: Demographics, Effects Of Human Disturbance, And Characteristics Of Calving Habitat, Bruce A. Stillings

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


La Gestion De La Faune Aux Aeroports, Edward C. Cleary , Richard A. Dolbeer Dec 1999

La Gestion De La Faune Aux Aeroports, Edward C. Cleary , Richard A. Dolbeer

Other Bird Strike and Aviation Materials

L’homme a toujours ete intrigue et inspire par la beaute des oiseaux et leur capacite de voler. Mais si les oiseaux ont colonise le ciel il y a quelque 150 millions d’annees, nous ne partageons leur espace aerien que depuis cent ans. Helas, ce partage forcement simultane est source de collisions. Certes, les oiseaux ne sont pas les seuls problemes des pilotes.


Black-Tailed Deer Habitat Changes In A Portion Of The Mount St. Helens Blast Zone, Ronald W. Davis Dec 1999

Black-Tailed Deer Habitat Changes In A Portion Of The Mount St. Helens Blast Zone, Ronald W. Davis

All-Inclusive List of Electronic Theses and Dissertations

This study utilized Landsat TM imagery to evaluate black-tailed deer habitat changes in a portion of the Mount Saint Helens blast zone in western Washington. The purpose of this study was to compare the post eruption vegetation changes with population trends for black tailed deer. The 55,000-acre study area comprises a Washington Department of Game Management unit (GMU 524) located to the northnorthwest of Mount St. Helens. Approximately 80% ofthe mostly forested study area was affected by lateral blast from the 1980 eruption. The area is predominantly private land managed for timber production but a small portion falls within the …


Vol. 22 No. 3-4 (1999): Pacific Studies Full Issue, The Jonathan Nāpela Center For Hawaiian And Pacific Islands Studies Dec 1999

Vol. 22 No. 3-4 (1999): Pacific Studies Full Issue, The Jonathan Nāpela Center For Hawaiian And Pacific Islands Studies

Pacific Studies

Pacific Studies is published two times a year by The Jonathan Nāpela Center for Hawaiian and Pacific Studies, Brigham Young University Hawai‘i #1979, 55–220 Kulanui Street, Lāʻie, Hawai‘i 96762, but responsibility for opinions expressed in the articles rests with the authors alone. Subscription rate is US$40.00 yearly, payable to The Jonathan Nāpela Center for Hawaiian and Pacific Studies. The Jonathan Nāpela Center for Hawaiian and Pacific Studies (formerly The Pacific Institute) is an organization funded by Brigham Young University Hawai‘i. The Center assists the University in meeting its cultural and educational goals by undertaking a program of teaching, research, and …


Intelligent Visualization And Automated Processing For Large Scale Geographic Information Systems, Yu Jiang Dec 1999

Intelligent Visualization And Automated Processing For Large Scale Geographic Information Systems, Yu Jiang

All-Inclusive List of Electronic Theses and Dissertations

This research focuses on developing a new output system that compacts maps in multiple projections into a single Geographic Information System (GIS) without visual errors, through constructing a discrete GIS database that is managed by a Relational Data Base Management System (RDBMS). Unlike in a traditional large GIS database, the data are "physically discrete but logically continuous." In a new discrete GIS database, every map keeps its individuality without a relationship to any other map, and the relationships among the maps are centrally managed by a RDBMS. A study site was chosen at the boundary of the state of Indiana …


The Probe, Issue 207 – December 1999 Dec 1999

The Probe, Issue 207 – December 1999

The Probe: Newsletter of the National Animal Damage Control Association

NADCA: A Proud History, A New Future -- Robert H. Schmidt, President, NADCA
Position Announcement: WILDLIFE ECOLOGIST - Urban Wildlife & Urban-Human Conflict Management Illinois Natural History Survey, Urbana-Champaign, IL
In Memoriam: Guy R. Hodge
Personnel Changes in USDA Wildlife Services: Two new State Directors
Book review: "Wildlife of the New Millennium: A Field Guide" by Buck Peterson. Published by Longstreet Press, Marietta, Georgia 1999. (152 pages, illustrated. $11.95) ISBN 1-56352-546-1
Euthanasia Chamber Available from Pioneer Wildlife Control of Westwood, MA

Abstracts from the 6th Annual Conference of The Wildlife Society - September 1999, Austin, TX
Public health significance of …


Evaluation Of Sampling Methodologies For Assessing Fish Species Richness In Ridge And Valley Streams In Chattanooga, Tennessee, Evan Robertson Crews Dec 1999

Evaluation Of Sampling Methodologies For Assessing Fish Species Richness In Ridge And Valley Streams In Chattanooga, Tennessee, Evan Robertson Crews

Masters Theses and Doctoral Dissertations

I evaluated the adequacy of different electrofishing approaches for estimating species richness in small Ridge and Valley streams. My study objectives were to determine the effects of the sampling season, reach length, habitat sequences surveyed, and sampling intensity on estimates of fish species richness. Fish assemblages were sampled at 18 sites across five streams in the Chattanooga, Tennessee area, May-June (spring) and July-August (summer) 1998. Reach lengths ranged from 103 to 278 m (30 to 61 times the mean stream width [MSW]). At each site, fish were collected using one or two backpack electrofishers within habitat-specific enclosures (riflle-run or pool). …


Comparison Of One-Dimensional And Two-Dimensional Hydrodynamic Modeling Approaches For Red River Basin, Sajjad Ahmad, Slobodan P. Simonovic Dec 1999

Comparison Of One-Dimensional And Two-Dimensional Hydrodynamic Modeling Approaches For Red River Basin, Sajjad Ahmad, Slobodan P. Simonovic

Civil and Environmental Engineering and Construction Faculty Research

EXECUTIVE SUMMARY

A devastating flood in Red River valley in 1997 emphasized the need to study the flood control measures in the Red River basin using state of the art modeling tools. The Red River and its floodplains can be modeled using one-dimensional, quasi two-dimensional or fully two-dimensional hydrodynamic models. Each modeling approach has its own advantages and limitations. The main purpose of this report is a comparison between one-dimensional (or quasi two dimensional) and fully two-dimensional hydrodynamic modeling approaches for modeling floods in the Red River basin.

A two-dimensional hydrodynamic model, MIKE 21, coupled with Geographic Information System (GIS) …


Water Current, Volume 31, No. 6, December 1999 Dec 1999

Water Current, Volume 31, No. 6, December 1999

Water Current Newsletter

Conference to Develop a Management Agenda for Nebraska's Water Future
From the Director: We Have a Long Way, But We Need to Go Further; Water Center Recognized as "Groundwater Guardian" Partner
NU Research Faculty Voice Desires for Strong Water Center Leadership
Citizen Stewards of the Pines and Plains
Fourth Water Tabloid Now Available from NU
Water News Briefs
Sixth Annual Undergrad Research Conference
Publications
National Geographic Society Awarding Science Grants
Call for Papers: Spatial Symposium in Reno, Nevada
Call for Papers: 11th Platte River Basin Symposium
Cooperation and Tension: The History, Reality and Future of Nebraska's Interstate Agreements


Introduction: Defining And Understanding Sustainability In Small Island States, Charles J. Stevens Dec 1999

Introduction: Defining And Understanding Sustainability In Small Island States, Charles J. Stevens

Pacific Studies

No abstract provided.


The Sustainable, The Expendable, And The Obsolete, Michael D. Lieber Dec 1999

The Sustainable, The Expendable, And The Obsolete, Michael D. Lieber

Pacific Studies

This is a preliminary exploration of the concept of sustainability and its potential usefulness to anthropologists. “Sustainable” is distinguished from “stable” and “viable” in terms of its implications of directionality of time, pointing both backward and forward. Given the time implications, the contexts of “sustainable Xs” (technology, activity, development, etc.) are crucial to explaining what happened to X in the past and prognosticating its future. The argument is illustrated by analyzing data on obsolete fishing practices on Kapingamarangi Atoll (Federated States of Micronesia), focusing on the contexts of change in political /religious organization in the twentieth century. Changing access to …


Development, Sustainability, And The Deforestation Of Samoa, Paul Shankman Dec 1999

Development, Sustainability, And The Deforestation Of Samoa, Paul Shankman

Pacific Studies

The forests of Samoa (formerly Western Samoa) are rapidly disappearing. This article reviews the history of Samoan deforestation, particularly during the last four decades, in the context of ideas about development and sustainability. It also examines the role of village agriculturalists in the process of deforestation. Recent economic, technological, and organizational changes have increased village agricultural expansion and, consequently, deforestation.


Reconnaissance Survey Of Lewis And Clark On The Missouri National Recreational River, Nebraska And South Dakota, Anne P. Diffendal, Gary E. Moulton, Michael Shambaugh-Miller, Robert F. Diffendal Jr. Dec 1999

Reconnaissance Survey Of Lewis And Clark On The Missouri National Recreational River, Nebraska And South Dakota, Anne P. Diffendal, Gary E. Moulton, Michael Shambaugh-Miller, Robert F. Diffendal Jr.

School of Natural Resources: Faculty Publications

Part I
Lewis and Clark on the Middle Missouri by Gary E. Moulton
Appendix: Principal Sites and Events
Select Bibliography

Part II
Locating Lewis and Clark Sites
Site #1 Floyd's Bluff
Site #2 Gass's Election
Site #3 Ionia Volcano
Site #4 1804 Mouth of the Vermillion River
Site #5 Spirit Mound
Site #6 Shannon's Absence
Site #7 Calumet Bluff
Site #8 "Ancient Fortifications"
Site #9 Mouth of the Niobrara River
Site # 10 Old Baldy


The Effect Of Divalent Cations On The Prophenoloxidase Enzyme Cascade Activity In The Freshwater Crayfish Cambarus Latimanus, Hans Skailand Eikaas Dec 1999

The Effect Of Divalent Cations On The Prophenoloxidase Enzyme Cascade Activity In The Freshwater Crayfish Cambarus Latimanus, Hans Skailand Eikaas

Theses and Dissertations

The effect of divalent cations such as cadmium, calcium, copper, lead and magnesium upon the prophenoloxidase system (proPO) was studied in hemocytes of the crayfish Cambarus latimanus. It was demonstrated that cadmium, calcium, copper and lead increased proPO activity significantly, whereas magnesium had no statistically significant effect on the system. Also, the molecular weight of the proPO enzyme was estimated using SDS-PAGE and found to be approximately 76 kDa.


Local And Landscape Factors Affecting Nest Site Selection And Nest Success Of Burrowing Owls In Western Nebraska, Rebecca T. Ekstein Dec 1999

Local And Landscape Factors Affecting Nest Site Selection And Nest Success Of Burrowing Owls In Western Nebraska, Rebecca T. Ekstein

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Legislating A Sustainable Land Ethic For New Zealand, Michèle D. Dominy Dec 1999

Legislating A Sustainable Land Ethic For New Zealand, Michèle D. Dominy

Pacific Studies

This article explores competing discourses of sustainability in New Zealand’s South Island. As active resource managers, high-country pastoralists’ conception of “country” contests predominant reductive and binary models of production/ conservation and economic resource/visual resource and suggests a more complicated dynamic between scientific and cultural paradigms of sustainability than has been acknowledged. This dynamic is captured in the internationally driven top-down concept of equitable sustainable land management with a dual commitment to both cultural and ecological diversity as defined locally, formulated as part of the United Nations Rio Declaration of 1992, agenda 21, chapter 13. I examine an emergent high-country “land …


Contributors: Vol 22 No. 3-4, The Jonathan Nāpela Center For Hawaiian And Pacific Islands Studies Dec 1999

Contributors: Vol 22 No. 3-4, The Jonathan Nāpela Center For Hawaiian And Pacific Islands Studies

Pacific Studies

Contributors list of Vol. 22 (1999): Pacific Studies Full Issue 3-4


Accounting For Change: Bringing Interdependence Into Defining Sustainability, Karen L. Nero Dec 1999

Accounting For Change: Bringing Interdependence Into Defining Sustainability, Karen L. Nero

Pacific Studies

“Sustainability,” the key word of international development bodies currently intervening in the restructuring of the Marshall Islands economy, is defined within Western economic conceptualizations. I argue that such characterizations are incomplete: they fail to capture the full nature of the ongoing Marshallese economy by focusing too narrowly on transfers related to the Compact of Free Association and by their partial understanding of Marshallese food systems and easy dichotomies between imported and local foods. The segregation of external interventions by sector further distorts their possible impact. Structural imbalances within the Marshallese and other Pacific nations’ economies have been exacerbated by the …


Artisanal Coral Reef Fisheries And Sustainable Development: The Arno Atoll Fisheries Association, Jim Hess Dec 1999

Artisanal Coral Reef Fisheries And Sustainable Development: The Arno Atoll Fisheries Association, Jim Hess

Pacific Studies

The concept of sustainable development is inexact, requiring additional specification in application. How the subject of analysis is bounded will have consequences for understanding what is being sustained as well as for determining whether something is sustained. Here I examine a fisheries development project in the Marshall Islands. Shifting boundaries, I create three accounts of the project. In the first account, which focuses on resources and monetary cost and benefits, the project is clearly unsustainable. In the second account, focusing on international relations, the project sustains the relations of power and dependency. In the third account, I suggest that evaluation …


Is Tonga's Mirab Economy Sustainable? A View From The Village And A View Without It, Mike Evans Dec 1999

Is Tonga's Mirab Economy Sustainable? A View From The Village And A View Without It, Mike Evans

Pacific Studies

The development implications of the now-classic MIRAB economic pattern for South Pacific microstates (with economies dominated by overseas remittances and foreign aid) have attracted considerable attention. Some scholars argue the MIRAB pattern is well entrenched and can be sustained with a minimum of undesirable social and economic outcomes. Others decry the acceptance of the dependency of South Pacific nations and argue for renewed effort toward the development of self-sustaining economies. I argue that the debate must directly address the underlying social relations that facilitate and shape migration and remittances. In Tonga, the movement of people from rural areas has wide-ranging …


Production Of The Subtropical Seagrass, Halodule Wrightii Aschers., In Lower Laguna Madre, Texas, Joseph L. Kowalski Dec 1999

Production Of The Subtropical Seagrass, Halodule Wrightii Aschers., In Lower Laguna Madre, Texas, Joseph L. Kowalski

Theses and Dissertations - UTB/UTPA

The autecology of shoal grass, Halodule wrightii Aschers., was studied at 1.2 m depth from June 1995 to February 1997 in Lower Laguna Madre (LLM), Texas. Halodule wrightii in LLM received about 47% surface irradiance, but otherwise displayed lower growth rates and biomass in nutrient-poor rhizosphere and water-column environments compared to H. wrightii populations in other Texas estuaries. High tissue N content and low C:N ratios belied low growth dynamics. Halodule wrightii in LLM is probably nutrient limited. A high nutrient demand by H. wrightii in a nutrient-poor environment may explain, in part, its gradual displacement by Thalassia testudinum and …


Year In Review - 1999, Annis Water Resources Institute Dec 1999

Year In Review - 1999, Annis Water Resources Institute

AWRI Reviews

No abstract provided.


Trace-Level Determination Of Fluorescently Labeled Phenoxy Acid Herbicides And The Study Of Their Crop Uptake And Soil Accumulation, Noura Saeed Al Nuaimi Dec 1999

Trace-Level Determination Of Fluorescently Labeled Phenoxy Acid Herbicides And The Study Of Their Crop Uptake And Soil Accumulation, Noura Saeed Al Nuaimi

Theses

A challenging problem facing the determination of phenoxy acid herbicides in samples is their low UV absorptivity and the interference associated with the matrix in which these analytes exist. This thesis is concerned with improving the detection limits of this group of herbicid as well as reduce or eliminate interference associated with the sample matrix.

Native phenoxy acid herbicides could be analyzed by high performance liquid chromatography (HPLC) with ultraviolet detection. Phenoxy herbicides were analyzed by HPLC employing a gradient conditions that allowed baseline resolution of all analytes used in this study in approximately 20 min. However, the average detection …


Reciprocal Transplantation Of The Desert Soil Crust: Can It Be Done?, Christina D. Cole Dec 1999

Reciprocal Transplantation Of The Desert Soil Crust: Can It Be Done?, Christina D. Cole

UNLV Theses, Dissertations, Professional Papers, and Capstones

A 100 meter X 100 meter study site was chosen at White Rock Springs in Red Rock Canyon National Conservation Area, Nevada. To examine Syntrichia caninervis, a desert crustal moss, reciprocal transplantations (20 mm and 40 mm diameter cores) were performed between shaded to shaded, exposed to exposed, and shaded to exposed microsites to determine if it was possible to transplant the study organism with reasonable survivorship. Transplants were inspected following rain events for percent hydration, number of dead stems, and change in percent cover. Data indicated that there was a low mortality rate of S. caninervis stems, and few …


Systemic Environmental Analysis Of The Legal Mechanisms For Controlling Air Pollution In The Las Vegas Valley, Richard Little Dec 1999

Systemic Environmental Analysis Of The Legal Mechanisms For Controlling Air Pollution In The Las Vegas Valley, Richard Little

UNLV Theses, Dissertations, Professional Papers, and Capstones

This study examines the air pollution control structure for the Las Vegas Valley. A System Dynamics computer model was created that represents the structure of the real world system for controlling air pollution, in order to examine how the current air pollution control system might behave in the future.


Evaporation Of Jet Fuels, Charles Eric Hack Dec 1999

Evaporation Of Jet Fuels, Charles Eric Hack

Theses and Dissertations

Determining the fate and transport of JP-8 jet fuel is a complex and important problem. As part of the startup procedures for jet engines, fuel is passed through aircraft engines before combustion is initiated. Because of the extremely low temperatures at northern tier Air Force bases, the unburned fuel does not evaporate readily and may come into contact with ground crew. To determine the amount and duration of contaminant contact, the evaporation of the emitted fuel must be modeled. The amount and composition of the fuel upon reaching the ground crew may be determined by droplet evaporation models that have …