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Full-Text Articles in Physical Sciences and Mathematics

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 …


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 …


Managing Gambel Oak In Southwestern Ponderosa Pine Forests: The Status Of Our Knowledge, Scott R. Abella Nov 2008

Managing Gambel Oak In Southwestern Ponderosa Pine Forests: The Status Of Our Knowledge, Scott R. Abella

Public Policy and Leadership Faculty Publications

Gambel oak (Quercus gambelii) is a key deciduous species in southwestern ponderosa pine (Pinus ponderosa) forests and is important for wildlife habitat, soil processes, and human values. This report (1) summarizes Gambel oak’s biological characteristics and importance in ponderosa pine forests, (2) synthesizes literature on changes in tree densities and fire frequencies since Euro-American settlement in pine-oak forests, (3) suggests management prescriptions for accomplishing various oak management objectives (for example, increasing diameter growth or acorn production), and (4) provides an appendix containing 203 Gambel oak literature citations organized by subject. Nine studies that reconstructed Gambel oak density changes since settlement …


Adaptive Management Report For The Clark County, Nevada Multiple Species Habitat Conservation Plan, Desert Conservation Program Oct 2008

Adaptive Management Report For The Clark County, Nevada Multiple Species Habitat Conservation Plan, Desert Conservation Program

Publications (C)

The Desert Conservation Program administers an incidental take permit for desert tortoise and 77 other species. The permit was issued in 2001 by the United States Fish and Wildlife Service in accordance with the Endangered Species Act. Compliance with the permit requires implementation of the Clark County Multiple Species Habitat Conservation Plan. This plan requires an adaptive management program and a biennial report by an independent science advisor to assess the status of the plan and make recommendations for future funding. The 2008 Adaptive Management Report reviews current data on land use trends, habitat loss, species status, plan implementation, programmatic …


Inside Unlv, Diane Russell, Shane Bevell, Jennifer Vaughan Oct 2008

Inside Unlv, Diane Russell, Shane Bevell, Jennifer Vaughan

Inside UNLV

No abstract provided.


Mojave Applied Ecology Notes Fall 2008, Alice Miller, Joshua Hoines, Scott R. Abella Oct 2008

Mojave Applied Ecology Notes Fall 2008, Alice Miller, Joshua Hoines, Scott R. Abella

Mojave Applied Ecology Notes

Effects of wildfires in Joshua Tree National Park, Blackbrush masting volunteer seed collection effort, new book chapter on Mojave revegetation, Natural Areas Association presentations.


Consequences Of More Extreme Precipitation Regimes For Terrestrial Ecosystems, S. D. Smith, C. Beier, Aimee T. Classen, Melinda D. Smith, Jana L. Heisler, S. W. Leavitt, Alan K. Knapp, D. Briske, Y. Luo, M. Reichstein, J. E. Bell, Philip A. Fay, R. Sherry, Benjamin Smith Oct 2008

Consequences Of More Extreme Precipitation Regimes For Terrestrial Ecosystems, S. D. Smith, C. Beier, Aimee T. Classen, Melinda D. Smith, Jana L. Heisler, S. W. Leavitt, Alan K. Knapp, D. Briske, Y. Luo, M. Reichstein, J. E. Bell, Philip A. Fay, R. Sherry, Benjamin Smith

Life Sciences Faculty Research

Amplification of the hydrological cycle as a consequence of global warming is forecast to lead to more extreme intra-annual precipitation regimes characterized by larger rainfall events and longer intervals between events. We present a conceptual framework, based on past investigations and ecological theory, for predicting the consequences of this underappreciated aspect of climate change. We consider a broad range of terrestrial ecosystems that vary in their overall water balance. More extreme rainfall regimes are expected to increase the duration and severity of soil water stress in mesic ecosystems as intervals between rainfall events increase. In contrast, xeric ecosystems may exhibit …


New Book Chapter Reviewing Mojave Desert Revegetation Practices Is Forthcoming, Scott R. Abella Oct 2008

New Book Chapter Reviewing Mojave Desert Revegetation Practices Is Forthcoming, Scott R. Abella

Public Policy and Leadership Faculty Publications

I was invited to write a chapter for a forthcoming book on Arid Environments to be published by Nova Science Publishers. This book is anticipated to appear in late 2008 or early 2009, and we will be able to provide additional details about the entire book at that time. I co-authored our chapter on revegetation with Alice Newton, Vegetation Manager at Lake Mead National Recreation Area. We systematically reviewed 23 published studies of planting or seeding native species in the Mojave Desert.


Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending September 30, 2008, Margaret N. Rees Sep 2008

Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending September 30, 2008, Margaret N. Rees

Wildlife Monitoring

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

  • Completion of translocation and augmentation efforts for 2008
  • Summer egg mass surveys completed
  • Coordination is ongoing to identify potential translocation sites near Moapa
  • Habitat improvements coordinated for Bighorn Sheep Spring
  • Annual Project Review Presentation provided to Clark County
  • All milestones and deliverables associated with the MSHCP project are on schedule

Project 2. Bald Eagle Winter Monitoring and Evaluation

  • Initial habitat suitability models and maps developed
  • Annual Project Review and Presentation given to Clark County
  • All MSHCP milestones and deliverables associated with this project are on schedule

Project 3. Peregrine Falcon Monitoring …


Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Year-End Progress Report, October 1, 2007 To September 30, 2008, Margaret N. Rees Sep 2008

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Year-End Progress Report, October 1, 2007 To September 30, 2008, Margaret N. Rees

Vegetation Monitoring

Executive Summary

  • The Weed Sentry program surveyed over 335 miles and 2,610 acres of transportation corridors on federal land in Clark County for incipient populations of exotic plants.
  • 18 manuscripts attained in-press or published status and one manuscript was submitted for review this year. Among published manuscripts, are one documenting Sahara mustard germination patterns (Western North American Naturalist), one assessing exotic species distributions in Clark County (Environmental Monitoring and Assessment), and another is a synthesis of burro effects on Mojave Desert vegetation (Environmental Management), and one assessing vegetation in grassy remnants of the Las Vegas Valley (Desert Plants)
  • Staff delivered …


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Report, Period Ending September 30, 2008, Margaret N. Rees Sep 2008

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Report, Period Ending September 30, 2008, Margaret N. Rees

Limnological Studies

Project 1: Technical input has been provided at eight advisory team meetings attended this quarter. Broad, overarching “Issues of Concern” developed for the Boulder Basin Adaptive Management Plan are currently under review by Drs. David Wong and Shawn Gerstenberger. A Selenium Management Plan is also under review.

Project 2: Data collected by the Southern Nevada Water Authority has been synthesized to summarize bacteria counts in high-use areas of Lakes Mead and Mohave. This information will be documented and interpreted for management use in a formal report in the upcoming quarter.

Project 3: A draft document titled “Suggested Standard Methods for …


Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer Sep 2008

Estimating Soil Seed Bank Characteristics In Ponderosa Pine Forests Using Vegetation And Forest-Floor Data, Scott R. Abella, Judith D. Springer

Public Policy and Leadership Faculty Publications

Soil seed banks are important for vegetation management because they contain propagules of species that may be considered desirable or undesirable for site colonization after management and disturbance events. Knowledge of seed bank size and composition before planning management activities facilitates proactive management by providing early alerts of exotic species presence and of abilities of seed banks to promote colonization by desirable species. We developed models in ponderosa pine (Pinus ponderosa) forests in northern Arizona to estimate the size and richness of mineral soil seed banks using readily observable vegetation and forestfloor characteristics. Regression models using three or fewer predictors …


Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella Sep 2008

Gambel Oak Growth Forms: Management Opportunities For Increasing Ecosystem Diversity, Scott R. Abella

Public Policy and Leadership Faculty Publications

Gambel oak (Quercus gambelii) clones have several different growth forms in southwestern ponderosa pine (Pinus ponderosa) forests, and these growth forms each provide unique wildlife habitat and resource values. The purposes of this note are to review published growth-form classifications for Gambel oak, provide examples of ecological effects of different growth forms, and summarize management strategies for promoting desired growth forms. Four different growth-form classifications have been published, which generally recognize variants of three basic forms: shrubby thickets of small-diameter stems, pole-sized clumps, and large trees. These growth forms exemplify ecological and management tradeoffs. For example, shrubby forms provide browse …


Changes In Gambel Oak Densities In Southwestern Ponderosa Pine Forests Since Euro-American Settlement, Scott R. Abella, Peter Z. Fule Sep 2008

Changes In Gambel Oak Densities In Southwestern Ponderosa Pine Forests Since Euro-American Settlement, Scott R. Abella, Peter Z. Fule

Public Policy and Leadership Faculty Publications

Densities of small-diameter ponderosa pine (Pinus ponderosa) trees have increased in southwestern ponderosa pine forests during a period of fire exclusion since Euro-American settlement in the late 1800s. However, less well known are potential changes in Gambel oak (Quercus gambelii) densities during this period in these forests. We reviewed published literature to summarize changes in oak density in ponderosa pine forests over the past 140 years and evaluated the possibility that large-diameter oaks have decreased in density. All nine studies examining oak density changes found that densities of small-diameter oaks have escalated. Increases ranged from 4- to more than 63-fold. …


Plant Recruitment In A Northern Arizona Ponderosa Pine Forest: Testing Seed- And Leaf Litter- Limitation Hypotheses, Scott R. Abella Aug 2008

Plant Recruitment In A Northern Arizona Ponderosa Pine Forest: Testing Seed- And Leaf Litter- Limitation Hypotheses, Scott R. Abella

Public Policy and Leadership Faculty Publications

Seed availability and leaf litter limit plant establishment in some ecosystems. To evaluate the hypothesis that these factors limit understory plant recruitment in Pinus ponderosa forests, I conducted a seeding and litter removal experiment at six thinned sites in the Fort Valley Experimental Forest, northern Arizona. Experimental seeding of four native species (Penstemon virgatus, Erigeron formosissimus, Elymus elymoides, and Festuca arizonica) and raking of litter occurred in 2005. Seeding resulted in a substantial recruitment of 14 to 103 seedlings/m2 (1 to 10/ft2) one month after seeding for two species (P. virgatus and E. elymoides), but these densities subsequently declined by …


Legislative Committee On Public Lands, Margaret N. Rees Jul 2008

Legislative Committee On Public Lands, Margaret N. Rees

Presentations (PLI)

The Public Lands Institute is dedicated to strengthening the national fabric that is essential for the protection, conservation, multiple use, and management of public lands.


Mojave Applied Ecology Notes Summer 2008, Doug Merkler, Scott R. Abella, Dianne N. Bangle, Donovan J. Craig, Jessica E. Spencer, Alex Suazo Jul 2008

Mojave Applied Ecology Notes Summer 2008, Doug Merkler, Scott R. Abella, Dianne N. Bangle, Donovan J. Craig, Jessica E. Spencer, Alex Suazo

Mojave Applied Ecology Notes

Soil climate project, rare plant monitoring, JFS update, granivory and Sahara mustard


Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Quarterly Progress Report, April 1, 2008 To June 30, 2008, Margaret N. Rees Jul 2008

Lake Mead National Recreation Area Vegetation Monitoring And Analysis: Quarterly Progress Report, April 1, 2008 To June 30, 2008, Margaret N. Rees

Vegetation Monitoring

Executive Summary

  • The Weed Sentry program surveyed over 182 miles of transportation corridors on federal land in Clark County for incipient populations of exotic plants.
  • Five manuscripts attained published or in-press status this quarter. The published manuscripts are (1) assessing vegetation in grassy remnants of the Las Vegas Valley (Desert Plants), (2) assessing exotic species distributions in Clark County (Environmental Monitoring and Assessment), (3) a synthesis of burro effects on Mojave Desert vegetation (Environmental Management), and (4) examining canopy-tree influences along a soil parent material gradient in (Journal of the Torrey Botanical Society).
  • Staff delivered eight presentations this quarter at …


We're Moving Into Unlv's New Science And Engineering Building, Scott R. Abella Jul 2008

We're Moving Into Unlv's New Science And Engineering Building, Scott R. Abella

Public Policy and Leadership Faculty Publications

Our research group is one of the few select groups that is moving into the new, $113-million UNLV Science and Engineering Building. The building is exclusively dedicated to research, and its four stories contain 200,000 square feet of research laboratories, faculty offices, and auditorium space for research symposia. Located on North Campus just northeast of the Biology Building, the building is anticipated to obtain LEED (Leadership in Energy and Environmental Design) certification.


Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending June 30, 2008, Margaret N. Rees Jun 2008

Lake Mead National Recreation Area Monitoring And Evaluation Of Sensitive Wildlife: Quarterly Progress Report, Period Ending June 30, 2008, Margaret N. Rees

Wildlife Monitoring

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

  • Translocation program completed this quarter at current active translocation sites.
  • Egg mass surveys at Blue Point Spring conducted approximately weekly; two additional egg massed collected from site for head-starting.
  • Frogs released at Blue Point and Rogers from egg masses collected at Blue Point in March and April, further augmentations planned.
  • Spring nocturnal surveys completed.
  • Coordination for potential translocation sites on BLM lands ongoing.
  • Habitat improvements coordinated and conducted at one new translocation site on BLM lands in the Gold Butte; site received frogs in April.
  • All milestones and deliverables associated with …


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

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

Limnological Studies

Hiring: Limnologist Dr. Wai Hing (David) Wong was hired and officially reported to work on 5/15/2008.

Project 1 and Project 2: Dr. Wong has commenced work on Projects 1 and 2.

Project 3: Dr. Wong has commenced work on Project 3. A comprehensive zebra/quagga mussel bibliography has been completed and published to the 100th Meridian Web site. Six interagency, multi-disciplinary quagga mussel meetings have been held. A quagga mussel substrate project has been initiated and, through the coordination efforts of this project, two other studies have been selected and refined to help determine the ecological impacts of quagga mussel infestation …


An Overview Of The Vegetation Research Program: Knowledge Services For Land Management, Scott R. Abella Apr 2008

An Overview Of The Vegetation Research Program: Knowledge Services For Land Management, Scott R. Abella

Fire Science Presentations

  • Provide knowledge services about the ecology and management of southwestern dryland ecosystems
  • Specialize in working with resource managers to conduct applied research
  • Conduct and provide research, monitoring, scientific literature synthesis, and technical assistance


Inside Unlv, Shane Bevell, Mamie Peers, David Ashley, Diane Russell, Michelle Mouton, Grace Russell Apr 2008

Inside Unlv, Shane Bevell, Mamie Peers, David Ashley, Diane Russell, Michelle Mouton, Grace Russell

Inside UNLV

No abstract provided.


Mojave Applied Ecology Notes Spring 2008, Lesley Defalco, E. Cayenne Engel, Scott R. Abella, Jessica E. Spencer, Jill E. Craig Apr 2008

Mojave Applied Ecology Notes Spring 2008, Lesley Defalco, E. Cayenne Engel, Scott R. Abella, Jessica E. Spencer, Jill E. Craig

Mojave Applied Ecology Notes

Post-fire restoration, fire chronosequence study, Joint Fire Science update, Weed Sentry program and DNWR surveys


Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: April 1, 2008, Margaret N. Rees Apr 2008

Limnological Assistance For The Lake Mead National Recreation Area In Meeting The Challenge Of The Water 2025 Initiative: Quarterly Progress Report, Period Ending: April 1, 2008, Margaret N. Rees

Limnological Studies

Hiring: A decision is anticipated in the upcoming weeks regarding the hiring of a limnologist. Two candidates were selected from among three qualified applicants for telephone interviews; they were subsequently interviewed in-person.

Project 1: Review of the draft Boulder Basin Adaptive Management Plan is on-going. Meetings of the Systems Conveyance and Operations Program (SCOP) Technical Advisory Teams were attended.

Project 2: Development of a white paper expressing the joint needs of the entities involved in Water 2025 projects is on-going; scientific review of data and reports related to bacteria in high-use areas of Lake Mead is underway.

Project 3: Discussions …


Plant Community Response To Fire: A Chronosequence Study, Scott R. Abella, E. Cayenne Engel Apr 2008

Plant Community Response To Fire: A Chronosequence Study, Scott R. Abella, E. Cayenne Engel

Public Policy and Leadership Faculty Publications

Fires are becoming more prevalent events across the landscape in the southwestern US. Over the next several decades the already arid southwest is predicted to become warmer and drier, with longer summers, and an increase of “extreme” weather events such as lightening inducing thunderstorms. While the “hotter and drier” forecast may indicate less abundant plant life, and thus less available biomass for fuel, exotic invasive plant species are becoming more dominant across the landscape with increases in human travel and commerce. Exotic species (particularly many of the invasive grasses) are adding fuel for the fires to burn when the annuals …


Fire Effects On Gambel Oak In Southwestern Ponderosa Pine-Oak Forests, Scott R. Abella, Peter Z. Fule Apr 2008

Fire Effects On Gambel Oak In Southwestern Ponderosa Pine-Oak Forests, Scott R. Abella, Peter Z. Fule

Public Policy and Leadership Faculty Publications

Gambel oak (Quercus gambelii) is ecologically and aesthetically valuable in southwestern ponderosa pine (Pinus ponderosa) forests. Fire effects on Gambel oak are important because fire may be used in pine-oak forests to manage oak directly or to accomplish other management objectives. We used published literature to: (1) ascertain historical fire regimes in pine-oak forests, (2) discern prescribed burning effects on Gambel oak survival and diameter growth, and (3) provide suggestions for using fire to manage oak. Frequent fire is part of Gambel oak’s historical environment, as historical fire return intervals often averaged less than 10 years in pine-oak forests. More …