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2008

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Full-Text Articles in Physical Sciences and Mathematics

Automatic Reaction To A Chemical Event Detected By A Low-Cost Wireless Chemical Sensing Network, Stephen Beirne, King Tong Lau, Brian Corcoran, Dermot Diamond Dec 2008

Automatic Reaction To A Chemical Event Detected By A Low-Cost Wireless Chemical Sensing Network, Stephen Beirne, King Tong Lau, Brian Corcoran, Dermot Diamond

Faculty of Science - Papers (Archive)

A test-scale wireless chemical sensor network (WCSN) has been deployed within a controlled Environmental Chamber (EC). The combined signals from the WCSN were used to initiate a controllable response to the detected chemical event. When a particular sensor response pattern was obtained, a purging cycle was initiated. Sensor data were continuously checked against user-defined action limits, to determine if a chemical event had occurred. An acidic contaminant was used to demonstrate the response of the sensor network. Once the acid plume was simultaneously detected by a number of wireless chemical sensor nodes, an automatic response action, which was the purging …


The 4 X 4 Semantic Model: Exploiting Data, Functional, Non-Functional And Execution Semantics Across Business Process, Workflow, Partner Services And Middleware Services Tiers, Amit P. Sheth, Karthik Gomadam Dec 2008

The 4 X 4 Semantic Model: Exploiting Data, Functional, Non-Functional And Execution Semantics Across Business Process, Workflow, Partner Services And Middleware Services Tiers, Amit P. Sheth, Karthik Gomadam

Kno.e.sis Publications

Business processes in the global environment increasingly encompass multiple partners and complex, rapidly changing requirements. In this context it is critical that strategic business objectives align with and map accurately to systems that support flexible and dynamic business processes. To support the demanding requirements of global business processes, we propose a comprehensive, unifying 4 X 4 Semantic Model that uses Semantic Templates to link four tiers of implementation with four types of semantics. The four tiers are the Business Process Tier, the Workflow Enactment Tier, the Partner Services Tier, and the Middleware Services Tier. The four types of semantics are …


Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending December 31, 2008, Margaret N. Rees Dec 2008

Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending December 31, 2008, Margaret N. Rees

Wildlife Monitoring

Project 1. Relict Leopard Frog Monitoring, Management, and Research

  • All milestones and deliverables associated with the MSHCP project are on schedule
  • Completion of 2008 monitoring survey efforts
  • Coordination is ongoing to identify potential translocation sites, including assisting efforts to identify a potential site in the western Grand Canyon
  • RLFCT meeting hosted and minutes of meeting drafted
  • Annual report provided to RLFCT, final draft in review
  • Sampling for the amphibian chytrid fungus conducted at many sites

Project 2. Bald Eagle Winter Monitoring and Evaluation

  • All MSHCP milestones and deliverables are on schedule
  • Planning and coordination of the 2009 Eagle Count conducted …


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Report, Period Ending December 31, 2008, Margaret N. Rees Dec 2008

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Report, Period Ending December 31, 2008, Margaret N. Rees

Limnological Studies

Project 1: Technical input has been provided at four advisory team meetings attended this quarter.

Project 2: A formal report titled, Surface Water Monitoring for Indicator Bacteria in High-use Sites of the Lake Mead National Recreation Area, has been prepared; an accompanying poster presentation for the Lake Mead Science Symposium is in preparation.

Project 3: A draft document titled, “Interagency Monitoring Action Plan (I-MAP): Quagga Mussels in Lakes Mead and Mohave” has been presented to an interagency core group to review and input. Six oral presentations related to quagga mussels are in preparation by this group for the Lake Mead …


Laser-Induced Photon-Branched Chain Reaction In A Chemically-Active Gas-Dispersed Medium, Thomas George, Renat Letfullin, Galen Duree Dec 2008

Laser-Induced Photon-Branched Chain Reaction In A Chemically-Active Gas-Dispersed Medium, Thomas George, Renat Letfullin, Galen Duree

Chemistry & Biochemistry Faculty Works

A promising avenue in the development of high-energy pulsed chemical HF/DF lasers and amplifiers is the utilization of a photon-branched chain reaction initiated in a two-phase active medium, that is, a medium containing a laser working gas and ultradispersed passivated metal particles. These particles are evaporated under the action of IR laser radiation which results in the appearance of free atoms, their diffusion into the gas, and the development of a photon-branching chain process, which involves photons as both reactants and products. The key obstacle here is the formation of a relatively large volume (in excess of 10^3 cm^3) of …


Laser-Induced Photon-Branched Chain Reaction In A Chemically-Active Gas-Dispersed Medium, Thomas F. George, Renat R. Letfullin, Galen C. Duree Dec 2008

Laser-Induced Photon-Branched Chain Reaction In A Chemically-Active Gas-Dispersed Medium, Thomas F. George, Renat R. Letfullin, Galen C. Duree

Thomas George

A promising avenue in the development of high-energy pulsed chemical HF/DF lasers and amplifiers is the utilization of a photon-branched chain reaction initiated in a two-phase active medium, that is, a medium containing a laser working gas and ultradispersed passivated metal particles. These particles are evaporated under the action of IR laser radiation which results in the appearance of free atoms, their diffusion into the gas, and the development of a photon-branching chain process, which involves photons as both reactants and products. The key obstacle here is the formation of a relatively large volume (in excess of 10^3 cm^3) of the …


Structure And Dynamics Of Metalloproteins In Live Cells, Jeremy D. Cook, James E. Penner-Hahn, Timothy L. Stemmler Dec 2008

Structure And Dynamics Of Metalloproteins In Live Cells, Jeremy D. Cook, James E. Penner-Hahn, Timothy L. Stemmler

Biochemistry and Molecular Biology Faculty Publications

X-ray absorption spectroscopy (XAS) has emerged as one of the premier tools for investigating the structure and dynamic properties of metals in cells and in metal containing biomolecules. Utilizing the high flux and broad energy range of X-rays supplied by synchrotron light sources, one can selectively excite core electronic transitions in each metal. Spectroscopic signals from these electronic transitions can be used to dissect the chemical architecture of metals in cells, in cellular components and in biomolecules at varying degrees of structural resolution. With the development of ever-brighter X-ray sources, X-ray methods have grown into applications that can be utilized …


Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang Dec 2008

Towards The Total Synthesis Of Thioviridamide: Thiyl Radical Approach To The Beta-Thioenamide Linkage Formation, Jung-Hoon Kang

Theses and Dissertations

We developed an approach to the β-thioenamide linkage contained in the S-(2-aminovinyl)cysteine (avCys) residue of thioviridamide.1,2 Kinetic and thermodynamic control of radical additions of thiols to ynamides were studied for the formation of β-thioenamide linkage. Thiyl radicals are electrophilic and ynamides are electron-rich alkynes. This complementary polarity of the radical and acceptor increases the likelihood of a successful radical addition reaction. Because little is known about these types of compounds (β-thioenamides), we were unsure what kinds of yields and stereoselectivities (cis vs. trans) to expect. The adduct stability is another issue to consider. Fortunately, under typical radical addition conditions, the …


Semantic Sensor Web, Amit P. Sheth, Cory Henson, Krishnaprasad Thirunarayan Dec 2008

Semantic Sensor Web, Amit P. Sheth, Cory Henson, Krishnaprasad Thirunarayan

Kno.e.sis Publications

No abstract provided.


Capturing Workflow Event Data For Monitoring, Performance Analysis, And Management Of Scientific Workflows, Matthew Valerio, Satya S. Sahoo, Roger Barga, Jared Jackson Dec 2008

Capturing Workflow Event Data For Monitoring, Performance Analysis, And Management Of Scientific Workflows, Matthew Valerio, Satya S. Sahoo, Roger Barga, Jared Jackson

Kno.e.sis Publications

To effectively support real-time monitoring and performance analysis of scientific workflow execution, varying levels of event data must be captured and made available to interested parties. This paper discusses the creation of an ontology-aware workflow monitoring system for use in the Trident system which utilizes a distributed publish/subscribe event model. The implementation of the publish/subscribe system is discussed and performance results are presented.


Early Post-Fire Recovery On A Heavily Visited Mojave Desert Burn: Red Rock Canyon Near Las Vegas, Nevada, Scott R. Abella, E. Cayenne Engel, Christina L. Lund, Jessica E. Spencer Dec 2008

Early Post-Fire Recovery On A Heavily Visited Mojave Desert Burn: Red Rock Canyon Near Las Vegas, Nevada, Scott R. Abella, E. Cayenne Engel, Christina L. Lund, Jessica E. Spencer

Fire Science Presentations

Wildfire has become widespread in southwestern USA deserts. In a record 2005 fire season in the Mojave Desert, for example, more than 385,000 hectares burned (Brooks and Matchett 2006). This burned area is approximately 3% of the entire Mojave Desert. Fueled in large part by exotic annual grasses, these fires burned desert ecosystems thought to have only burned infrequently historically. Burns now occupy significant portions of desert landscapes, posing prominent management challenges. Improving our understanding of plant recovery on desert burns is important for evaluating future fire hazard, whether natural revegetation will meet management objectives, and for planning active revegetation …


Using A Diverse Seed Mix To Establish Native Plants On A Sonoran Desert Burn, Scott R. Abella, John L. Gunn, Mark L. Daniels, Judith D. Springer, Susan E. Nyoka Dec 2008

Using A Diverse Seed Mix To Establish Native Plants On A Sonoran Desert Burn, Scott R. Abella, John L. Gunn, Mark L. Daniels, Judith D. Springer, Susan E. Nyoka

Fire Science Presentations

  • Revegetating burned areas is a formidable challenge facing resource managers in southwestern United States arid lands.
  • Natural revegetation of desert burns by native species may be slow, or dominated by exotic annual grasses that perpetuate a frequent-fire regime.
  • Resource managers may have several reasons for actively revegetating burns with native species, such as for providing competition with exotic species, minimizing soil erosion and dust pollution, and improving aesthetics.
  • The use of native species in revegetation has been limited by a lack of available seed and by findings that native desert species are difficult to establish (e.g., Bainbridge and Virginia 1990, …


Post-Fire Plant Recovery In The Mojave And Sonoran Deserts Of Western North America, Scott R. Abella, Public Lands Institute, Department Of Environmental Studies, University Of Nevada, Las Vegas Dec 2008

Post-Fire Plant Recovery In The Mojave And Sonoran Deserts Of Western North America, Scott R. Abella, Public Lands Institute, Department Of Environmental Studies, University Of Nevada, Las Vegas

Fire Science Presentations

Fire is thought to have been generally rare historically in the Mojave and Sonoran Deserts. However, invasion by exotic grasses (e.g., Schismus spp.) has increased fuel continuity, promoting fire in these deserts. Succession and recovery are not well understood processes in deserts, nonetheless for a novel disturbance like fire. In addition to helping build theories of desert succession and recovery, information on post-fire recovery has numerous practical implications (e.g., determining whether active revegetation is needed). Systematic reviews provide a means for obtaining literature using reproducible search criteria. This approach facilitates a balanced appraisal of available information, synthesizes scattered literature, and …


Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto Dec 2008

Giant Sequoia Insect, Disease, And Ecosystem Interactions, Douglas D. Piirto

Douglas D. Piirto

Individual trees of giant sequoia (Sequoia gigantea [Lindl.] Decne.) have demonstrated a capacity to attain both a long life and very large size. It is not uncommon to find old-growth giant sequoia trees in their native range that are 1,500 years old and over 15 feet in diameter at breast height. The ability of individual giant sequoia trees to survive over such long periods of time has often been attributed to the species high resistance to disease, insect, and fire damage. Such a statement, however, is a gross oversimplification, given broader ecosystem and temporal interactions. For example, why isn't there …


Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson Dec 2008

Efficacy Of Herbicide Application Methods Used To Control Tanoak (Lithocarpus Densiflorus) In An Uneven-Aged Coast Redwood Management Context, Douglas D. Piirto, Brenda Smith, Eric K. Huff, Scott T. Robinson

Douglas D. Piirto

Three methods of tanoak (Lithocarpus densiflorus [Hook. & Arn.] Rehd.) control involving the application of the amine or ester form of triclopyr were evaluated in this coast redwood uneven-aged forest management study of herbicides. A cut-stump application with the amine form of triclopyr (Garlon 3A), frill cut with the amine form of triclopyr, basal-bark (outer surface) with the ester form of triclopyr (Garlon 4), and an untreated control were replicated three times. The tanoak control results in Douglas-fir (Pseudotsuga menziesii [Mirb.] Franco) and/ or coast redwood (Sequoia sempervirens [D. Don] Endl.) predominated stands obtained in earlier studies …


Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto Dec 2008

Cost-Effective Fire Management For Southern California's Chaparral Wilderness: An Analytical Procedure, Chris A. Childers, Douglas D. Piirto

Douglas D. Piirto

Fire management has always meant fire suppression to the managers of the chaparral covered southern California National Forests. Today, Forest Service fire management programs must be cost effective, while wilderness fire management objectives are aimed at recreating natural fire regimes. A cost-effectiveness analysis has been developed to compare fire management options for meeting these objectives in California's chaparral wilderness. This paper describes the analytical procedure using examples from a study currently being conducted for the Los Padres National Forest, and discusses some preliminary results.


Three-Dimensional Microfluidic Devices Fabricated In Layered Paper And Tape, Andres W. Martinez, Scott T. Phillips, George M. Whitesides Dec 2008

Three-Dimensional Microfluidic Devices Fabricated In Layered Paper And Tape, Andres W. Martinez, Scott T. Phillips, George M. Whitesides

Chemistry and Biochemistry

This article describes a method for fabricating 3D microfluidic devices by stacking layers of patterned paper and double-sided adhesive tape. Paper-based 3D microfluidic devices have capabilities in microfluidics that are difficult to achieve using conventional open-channel microsystems made from glass or polymers. In particular, 3D paper-based devices wick fluids and distribute microliter volumes of samples from single inlet points into arrays of detection zones (with numbers up to thousands). This capability makes it possible to carry out a range of new analytical protocols simply and inexpensively (all on a piece of paper) without external pumps. We demonstrate a prototype 3D …


Minerva 2008, The Honors College Dec 2008

Minerva 2008, The Honors College

Minerva

This issue of Minerva includes an article on the completion of the restoration of Colvin Hall; a reflection by Ruth Nadelhaft, former UMaine Honors program director; and an article on Honors alumnus and Nobel Peace Prize winner Bernard Lown and his 2008 Rezendes Visiting Scholar in Ethics Lecture/Distinguished Honors Graduate Lecture.


On The Movement Of Beluga Whales In Cook Inlet, Alaska: Simulations Of Tidal And Environmental Impacts Using A Hydrodynamic Inundation Model, Tal Ezer, Roderick Hobbs, Lie-Yauw Oey Dec 2008

On The Movement Of Beluga Whales In Cook Inlet, Alaska: Simulations Of Tidal And Environmental Impacts Using A Hydrodynamic Inundation Model, Tal Ezer, Roderick Hobbs, Lie-Yauw Oey

CCPO Publications

The population of beluga whales in Cook Inlet, Alaska, is in decline, and since 2000 these whales have been under consideration for designation as "endangered" under the Endangered Species Act (and were placed on the list in October 2008, just before this article went to press). In order to study environmental and hydrodynamic impacts on the belugas' movements and survival in the unique habitat of the inlet, a three-dimensional ocean circulation and inundation model is combined with satellite-tracked beluga whale data. Model-wale data comparisons from two whale paths during a five-day period (september 17-21, 2000) covering 10 tidal cycles suggest …


Lidar-Derived Benthic Habitat Maps Enable The Quantification Of Potential Dredging Impacts To Coral Reef Ecosystems, Brian K. Walker, Richard E. Dodge, David S. Gilliam Dec 2008

Lidar-Derived Benthic Habitat Maps Enable The Quantification Of Potential Dredging Impacts To Coral Reef Ecosystems, Brian K. Walker, Richard E. Dodge, David S. Gilliam

Marine & Environmental Sciences Faculty Proceedings, Presentations, Speeches, Lectures

An essential component to the analysis of ecosystem services is to characterize and define the major habitats within the area of interest. Aerial photography and/or satellite imagery coupled with geographic information systems (GIS) are frequently used to identify and quantify habitats in open terrestrial ecosystems. However, it is more difficult to successfully apply this methodology to deeper, <20 m, underwater environments. Light detection and ranging (LIDAR), a relatively new remote sensing technology that provides detailed bathymetry, can be used when adequate imagery is not available. This study uses LIDAR as the basis to characterize various benthic habitats in a coral reef ecosystem in order to quantify the habitats for a Habitat Equivalency Analysis (HEA) related to planned dredging activities to expand the Port Everglades entrance channel, Broward County, FL. As part of a regional mapping effort, marine benthic habitats were characterized for Broward County, FL. A mosaic of interpolated, sunshaded, laser bathymetry data served as the foundation upon which acoustic ground discrimination, limited subbottom profiling and aerial photography, and groundtruthing data were added in a GIS to aid in interpretation of benthic habitats. Expert-driven visual interpretation outlined geomorphological features in the LIDAR data at a scale of 1:6000 with a minimum mapping unit of 1 acre. The map of Broward County yielded a high overall accuracy of 89.6%. To quantify the potential dredging impacts, the habitat layer was clipped in GIS to the boundaries of anticipated direct and indirect impacts of the proposed project. Then the area of each clipped polygon was totaled for each habitat by impact type. HEA and Florida’s Uniform Mitigation Assessment Method (UMAM) were performed using these areas. This work would not have been possible using satellite imagery or aerial photography alone and illustrates the capability of relatively new remote sensing technologies to aid in the definition and quantification of habitats for ecosystem service analyses.


Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo Dec 2008

Effects Of Olfactory And Visual Predators On Nest Success And Nest-Site Selection Of Waterfowl In North Dakota, Jennifer Borgo

Green Canyon Environmental Research Area, Logan Utah

No abstract provided.


Preliminary Perspectives On The Health Needs Of Pastoral Women On The Borana Plateau Using Participatory Approaches, D. Layne Coppock, Seyoum Tezera, Solomon Desta Dec 2008

Preliminary Perspectives On The Health Needs Of Pastoral Women On The Borana Plateau Using Participatory Approaches, D. Layne Coppock, Seyoum Tezera, Solomon Desta

Environment and Society Faculty Publications

Since 2000, the PARIMA project has conducted participatory research and outreach among pastoralists in southern Ethiopia. This has led to notable achievements in terms of forming collective-action groups dominated by women, stimulation of sustainable micro-finance and micro-enterprise activities, and improving linkages of pastoral producers to livestock markets. Despite such gains, there are many other challenges to be addressed. One is poor human health. PARIMA researchers used participatory and qualitative methods to conduct a preliminary assessment of women’s health problems among members of six, well-established collective-action groups from the Borana and Gugi zones in the Oromia Regional State during 2008. Conventional …


Integrating Landscapes That Have Experienced Rural Depopulation And Ecological Homogenization Into Tropical Conservation Planning, Aerin L. Jacob, Ismael Vaccaro, Raja Sengupta, Joel N. Hartter, Colin A. Chapman Dec 2008

Integrating Landscapes That Have Experienced Rural Depopulation And Ecological Homogenization Into Tropical Conservation Planning, Aerin L. Jacob, Ismael Vaccaro, Raja Sengupta, Joel N. Hartter, Colin A. Chapman

Geography

If current trends of declining fertility rates and increasing abandonment of rural land as a result of urbanization continue, this will signal a globally significant transformation with important consequences for policy makers interested in conservation planning. This transformation is presently evident in a number of countries and projections suggest it may occur in the future in many developing countries. We use rates of population growth and urbanization to project population trends in rural areas for 25 example countries. Our projections indicate a general decline in population density that has either occurred already (e.g., Mexico) or may occur in the future …


Remarks On The Stability Of Some Size-Structured Population Models Iii: The Case Of Constant Inflow Of Newborns, Mohammed El-Doma Dec 2008

Remarks On The Stability Of Some Size-Structured Population Models Iii: The Case Of Constant Inflow Of Newborns, Mohammed El-Doma

Applications and Applied Mathematics: An International Journal (AAM)

The stability of some size-structured population dynamics models are investigated. We determine the steady states and study their stability. We also give examples that illustrate the stability results. The results in this paper generalize previous results, for example, see Calsina, et al. (2003), El- Doma (2006) and El-Doma (2008).


An Assessment Of Alternative Feed Ingredients In Practical Diets For Florida Pompano (Trachinotus Carolinus) Held In Low Salinity Recirculating Systems, Terhea Nichole Williams Dec 2008

An Assessment Of Alternative Feed Ingredients In Practical Diets For Florida Pompano (Trachinotus Carolinus) Held In Low Salinity Recirculating Systems, Terhea Nichole Williams

Electronic Theses and Dissertations

The identification of alternative protein sources for partial or whole replacement of fishmeal (FM) is a priority in the development of suitable, low cost feed formulations for the Florida pompano (Trachinotus carolinus). To evaluate alternative feed ingredients for the potential replacement of FM in diets fed to juvenile pompano, a series of four experiments were conducted. The objectives of Experiments 1 and 2 were to determine the apparent digestibility of crude protein (ADCP), energy (ADE), and apparent amino acid availability (AAAA) of three plant based ingredients (soybean meal (SBM), soy protein isolate (SPI), corn gluten meal (CGM)) and three by-product …


What Are Consumers In Moyale, Kenya Willing To Pay For Improved Milk Quality?, D. Layne Coppock, Francis O. Wayua, Mohamed G. Shibia, Moses S. Mamo Dec 2008

What Are Consumers In Moyale, Kenya Willing To Pay For Improved Milk Quality?, D. Layne Coppock, Francis O. Wayua, Mohamed G. Shibia, Moses S. Mamo

Environment and Society Faculty Publications

Pastoralists in northern Kenya and southern Ethiopia may be able to diversify income by selling milk to urban residents. However, milk sold in open-air markets is often low in quality because it has been transported long distances without refrigeration and is subject to spoilage, or because milk is adulterated prior to sale to boost volume or enhance appearance. Open-air markets are characterized by low-income consumers who must make choices about milk quality with virtually no information other than their own sensory perceptions. PARIMA researchers used an experimental-auction approach to determine what residents in Moyale, Kenya, are willing to pay (WTP) …


Growing Fields Of Interest: Using An Expand And Reduce Strategy For Domain Model Extraction, Christopher Thomas, Pankaj Mehra, Roger Brooks, Amit P. Sheth Dec 2008

Growing Fields Of Interest: Using An Expand And Reduce Strategy For Domain Model Extraction, Christopher Thomas, Pankaj Mehra, Roger Brooks, Amit P. Sheth

Kno.e.sis Publications

Domain hierarchies are widely used as models underlying information retrieval tasks. Formal ontologies and taxonomies enrich such hierarchies further with properties and relationships associated with concepts and categories but require manual effort; therefore they are costly to maintain, and often stale. Folksonomies and vocabularies lack rich category structure and are almost entirely devoid of properties and relationships. Classification and extraction require the coverage of vocabularies and the alterability of folksonomies and can largely benefit from category relationships and other properties. With Doozer, a program for building conceptual models of information domains, we want to bridge the gap between the vocabularies …


Successful Implementation Of Collective Action And Human-Capacity Building Among Pastoralists In Southern Ethiopia: Lessons Learned, 2001-2008, D. Layne Coppock, Seyoum Tezera, Solomon Desta, Getachew Gebru Dec 2008

Successful Implementation Of Collective Action And Human-Capacity Building Among Pastoralists In Southern Ethiopia: Lessons Learned, 2001-2008, D. Layne Coppock, Seyoum Tezera, Solomon Desta, Getachew Gebru

Environment and Society Faculty Publications

Since 2000 the PARIMA project has implemented pilot risk-management activities among poverty-stricken, semi-settled pastoralists in southern Ethiopia. The goal has been to improve human welfare via collective action and capacity building. Outcomes include progress in income generation, asset conservation, and livelihood diversification. The approach has been unique to southern Ethiopia in that a bottom-up, participatory perspective has dominated. It has focused on the priorities and felt needs of local people rather than top-down development of livestock or agricultural technology. Fifty-nine collective-action groups were created. Dominated by women, they have included over 2,300 members and most groups have been recently merged …


Decadal-Scale Changes On Coral Reefs In Quintana Roo, Mexico, Thaddeus Allen Nicholls Dec 2008

Decadal-Scale Changes On Coral Reefs In Quintana Roo, Mexico, Thaddeus Allen Nicholls

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In 1988 data on coral reef community composition were collected from two areas, Akumal and Chemuyil, Quintana Roo, Mexico, ranging from 5-35m depth. These areas were revisited in 2005 and data were collected by the same methods and at the same depths as in 1988. Data from 1988 and 2005 were compared to determine if the coral reefs had undergone significant changes, and what specific changes had occurred. Chi-square analysis determined that community composition data collected in 1988 are significantly different from data collected in 2005 at all sites and depths within the categories of corals, gorgonians, sponges, and macroalgae. …


Are Cattle Die-Offs Predictable On The Borana Plateau, D. Layne Coppock, Getachew Gebru, Solomon Desta, Sintayehu Mesele, Seyoum Tezerra Dec 2008

Are Cattle Die-Offs Predictable On The Borana Plateau, D. Layne Coppock, Getachew Gebru, Solomon Desta, Sintayehu Mesele, Seyoum Tezerra

Environment and Society Faculty Publications

Drought regularly affects rangelands and contributes to high death rates for livestock and poverty for pastoralists. But do livestock losses occur randomly simply when rainfall is low, or are they cyclical and predictable? Previously, PARIMA researchers proposed that high stocking rates—combined with low rainfall—trigger livestock die-offs on the Borana Plateau. It takes about six years for animal numbers to recover, setting the stage for another die-off when a dry year occurs. This “boom-and-bust” cycle is based on observed herd crashes in 1983-5, 1991-3, and 1998-9. Researchers predicted in 2002 that the next major die-off would occur during 2004-06, and one …