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Full-Text Articles in Natural Resources and Conservation

The Role Of Adaptive Capacity In Creating Fire-Adapted Human Communities, Pamela J. Jakes, Matthew S. Carroll, Travis B. Paveglio, Soren Newman Jan 2010

The Role Of Adaptive Capacity In Creating Fire-Adapted Human Communities, Pamela J. Jakes, Matthew S. Carroll, Travis B. Paveglio, Soren Newman

Joint Fire Science Program Research Project Reports

In this research we sought answers to the question: What are the social characteristics and conditions of human communities that promote adaptive capacity for wildfire? The Quadrennial Fire Review (USDA and USDI 2009) promotes a goal of “achieving fire-adapted communities” in the wildland urban interface (WUI), and identifies metrics for determining whether a community is fire-adapted. While these metrics address some of the biophysical conditions necessary for fire-adapted human communities, they offer little insight into the social elements that promote or sustain adaptive capacity. Adaptive capacity refers to the individual and collective resources, capabilities, and actions that alleviate the risk …


2010 Western Mensurationists’ Conference, David Affleck, John Goodburn, Christopher Keyes, Renate Bush Jan 2010

2010 Western Mensurationists’ Conference, David Affleck, John Goodburn, Christopher Keyes, Renate Bush

Joint Fire Science Program Research Project Reports

The 2010 Western Mensurationists’ Conference in Missoula, MT, drew together forest scientists and land managers with primary expertise in the measurement and modeling of forest resources. The meeting provided an opportunity to focus the collective technical expertise of this group on crossdisciplinary conifer crown modeling issues that are of increasing importance to existing and emerging forest management strategies in western North America. Thus, a special invited session on conifer crown modeling results and opportunities was added to the conference agenda together with a participatory workshop on crown modeling needs and challenges. Funding was provided by the Joint Fire Science Program …


A Proposal To Improve Performance Of The Forest Vegetation Simulator - Fire And Fuels Extension, Dave C. Cawrse, Michael G. Van Dyke, Nicolas Nicholas L. Crookston, Donald Robinson, Sarah Beukema Jan 2010

A Proposal To Improve Performance Of The Forest Vegetation Simulator - Fire And Fuels Extension, Dave C. Cawrse, Michael G. Van Dyke, Nicolas Nicholas L. Crookston, Donald Robinson, Sarah Beukema

Joint Fire Science Program Research Project Reports

The Forest Vegetation Simulator (FVS) and its associated Fire and Fuels Extension (FFE) have been used to provide information required by larger software systems like the Interagency Fuels Treatment - Decision Support System (IFT-DSS). Interacting with FVS in an automated fashion has been difficult, and simulations with very large numbers of stands, such as those necessary for landscape analyses for fire planning, could take a significant amount of time to process. This project was designed to: (A) develop a requirements document considering Service Oriented Architecture and how that may apply to FVS, and how FVS will be used interactively; (B) …


Assessment Of Canopy Fuel Loading Across A Heterogeneous Landscape Using Lidar, Kenneth L. Clark, Nicholas Skowronski, Michael Gallagher, Nicholas Carlo, Michael Farrell, Melanie R. Maghirang Jan 2010

Assessment Of Canopy Fuel Loading Across A Heterogeneous Landscape Using Lidar, Kenneth L. Clark, Nicholas Skowronski, Michael Gallagher, Nicholas Carlo, Michael Farrell, Melanie R. Maghirang

Joint Fire Science Program Research Project Reports

Our research used light detection and ranging (LiDAR) systems coupled with sequential harvesting of Pitch pine (Pinus rigida Mill.) to quantify canopy fuels in three dimensions across a large, heterogeneous landscape impacted by multiple wildfires, prescribed burns and insect defoliation events. We used a three-tiered approach; 1) calibration of upward sensing profiling LiDAR data with sequential harvesting of 20 x 20 meter plots to quantify the mass of foliage, branches and stems in Pitch pine canopies in 1-meter height layers, 2) scaling results to the landscape scale using previously-published relationships between upward sensing and downward sensing scanning LiDAR systems in …


Annual Brome Biocontrol After Wildfire Using A Native Fungal Seed Pathogen, Susan E. Meyer, Phil S. Allen, Julie Beckstead, Michael Gregg, Heidi Newsome, Kathleen Harcksen, Gary Kidd, Glenn Paulsen, Karen Prentice, Dana Quinney, David Wilderman, Stephanie Carlson, Suzette Clement, Duane Smith, Thom Stewart, Katie Merrill, Keith Merrill, Kedra Foote, Stephen Harrison, Kelly Bergen, Brian Connelly, Trevor Davis, Sandra Dooley, Michael Huck, Laura Street, Lauren Miller Jan 2010

Annual Brome Biocontrol After Wildfire Using A Native Fungal Seed Pathogen, Susan E. Meyer, Phil S. Allen, Julie Beckstead, Michael Gregg, Heidi Newsome, Kathleen Harcksen, Gary Kidd, Glenn Paulsen, Karen Prentice, Dana Quinney, David Wilderman, Stephanie Carlson, Suzette Clement, Duane Smith, Thom Stewart, Katie Merrill, Keith Merrill, Kedra Foote, Stephen Harrison, Kelly Bergen, Brian Connelly, Trevor Davis, Sandra Dooley, Michael Huck, Laura Street, Lauren Miller

Joint Fire Science Program Research Project Reports

A major problem in post-fire restoration of semi-arid shrublands dominated by annual bromes is the presence of carryover seed banks that cannot be controlled using conventional methods. These seeds can provide significant competition for seeded species in the years following treatment. We investigated the feasibility of using a naturally occurring seed pathogen, the ascomycete Pyrenophora semeniperda, as a biocontrol organism for eliminating this carryover seed bank. We carried out the necessary technology development to create and apply field inoculum to cheatgrass- or red brome-infested areas (both burned and unburned) at six sites located in three states across two years of …


Changes In Vegetation And Fuels Due To The Warm Fire On The Kaibab National Forest, Melissa A. Mcmaster, Andrea Thode, Brian Brost, Matthew Williamsen, Ethan Aumack, Dave Mertz Jan 2010

Changes In Vegetation And Fuels Due To The Warm Fire On The Kaibab National Forest, Melissa A. Mcmaster, Andrea Thode, Brian Brost, Matthew Williamsen, Ethan Aumack, Dave Mertz

Joint Fire Science Program Research Project Reports

Fire is a significant and essential disturbance in ponderosa pine ecosystems but the management and the re-introduction of fire across the landscape is a difficult task for land managers. In this study we worked with land managers, stakeholders and researchers to examine the effects of a large wildfire on the Kaibab Plateau in northern Arizona. We analyzed litter and duff depth, downed woody debris and understory vegetation responses to low and high burn severity and assessed the response of the understory vegetation to seeding with Lolium perenne ssp. multiflorum in high severity burn areas. To assist land managers in future …


Continued Evaluation Of Post-Fire Recovery And Treatment Effectiveness For Validation Of The Ermit Erosion Model, Peter R. Robichaud, William J. Elliot, Joseph W. Wagenbrenner, Sarah A. Lewis, Louise E. Ashmun, Peter M. Wohlgemuth, Robert E. Brown Jan 2010

Continued Evaluation Of Post-Fire Recovery And Treatment Effectiveness For Validation Of The Ermit Erosion Model, Peter R. Robichaud, William J. Elliot, Joseph W. Wagenbrenner, Sarah A. Lewis, Louise E. Ashmun, Peter M. Wohlgemuth, Robert E. Brown

Joint Fire Science Program Research Project Reports

The use and cost of post-fire emergency stabilization treatments continues to grow. To help maximize the impact of these treatments, many assessment teams use the Erosion Risk Management Tool (ERMiT) erosion model to predict postfire erosion and mitigation effects. However, despite several completed JFSP projects, the long-term effects of these treatments remain unknown, and the ERMiT model has not been validated. Long-term post-fire erosion and runoff data on a variety of mulches and erosion barriers were collected using 12 existing sites throughout the Western U.S. The agricultural straw and wood strand mulch treatments were very effective at reducing erosion and …


Effectiveness Of Fuel Treatments For Mitigating Wildfire Severity: A Manager‐Focused Review And Synthesis, Philip N. Omi, Erik J. Martinson Mr. Jan 2010

Effectiveness Of Fuel Treatments For Mitigating Wildfire Severity: A Manager‐Focused Review And Synthesis, Philip N. Omi, Erik J. Martinson Mr.

Joint Fire Science Program Research Project Reports

The 2008 Request for Applications from the Joint Fire Science Program called for a synthesis of the extant literature that addresses the effectiveness of fuel treatments. We employed a four‐pronged approach to address this task, including several scoping exercises with land managers, a literature review, a meta‐analysis, and development of an online pictorial database.


An Enhanced Online Piled Fuels Biomass Calculator, Clinton S. Wright, Paige C. Eagle Jan 2010

An Enhanced Online Piled Fuels Biomass Calculator, Clinton S. Wright, Paige C. Eagle

Joint Fire Science Program Research Project Reports

A web-programming project was undertaken to allow users of the online Hand-piled Fuels Biomass Calculator to also estimate the volume, biomass and potential emissions of mechanically piled fuels. Machine pile calculations encoded in the decision support software CONSUME 3.0 were added to the online Calculator to achieve this objective. In addition, the ability to batch process piled fuels data was added to the online Calculator to ease data input for large analysis projects. A stand-alone version of the Calculator was developed for users without access to the Internet. As it is executed within a standard web browser (e.g., Microsoft Internet …


Evaluating The Effects Of Pinyon Thinning Treatments At A Wildland Urban Interface, J. R. Matchett, Matthew L. Brooks, Anne Halford, Dale Johnson, Helen Smith Jan 2010

Evaluating The Effects Of Pinyon Thinning Treatments At A Wildland Urban Interface, J. R. Matchett, Matthew L. Brooks, Anne Halford, Dale Johnson, Helen Smith

Joint Fire Science Program Research Project Reports

This study evaluated the short-term effects of thinning methods for pinyon pine woodlands at two sites in the southwestern Great Basin. Both cut/pile/burn and mastication treatments were equally effective at reducing the target fuels which were mature, live pinyon trees. Application costs though differed substantially, with the cut/pile/burn technique being less expensive. Thinning treatments increased the abundance of herbaceous vegetation, although in some cases the strength of the increase was constrained by the level of pre-treatment tree dominance. Increases in perennial grass cover and density in response to thinning were usually greatest at lower levels of pre-treatment pinyon dominance, whereas …


Exploring The Traditional Use Of Fire In The Coastal Mountains Of Central California, Brent E. Johnson, Rand R. Everett, Kent G. Lightfoot, Charles J. Stiplen Jan 2010

Exploring The Traditional Use Of Fire In The Coastal Mountains Of Central California, Brent E. Johnson, Rand R. Everett, Kent G. Lightfoot, Charles J. Stiplen

Joint Fire Science Program Research Project Reports

This study brought together a team of ecologists, archaeologists, environmental historians, indigenous peoples, and land managers within a research framework combining an ethnographic investigation of traditional practices with cutting-edge paleoecological techniques to answer questions about Indian utilization of fire as an ecological and cultural landscape management tool in Central Coastal California. The study was designed around four key elements: (1) examining fire regimes for research sites using a combination of fire scar dendrochronology, phytoliths, archaeology, historical information, and traditional ecological knowledge; (2) attempting to formalize a methodology for using phytoliths to estimate the fire return interval and intensity in grassland …


Fire Regimes Of The Southern Appalachian Mountains: Temporal And Spatial Variability Over Multiple Scales And Implications For Ecosystem Management, Charles W. Lafon, Henri D. Grissino-Mayer, Sally P. Horn, Robert N. Klein Jan 2010

Fire Regimes Of The Southern Appalachian Mountains: Temporal And Spatial Variability Over Multiple Scales And Implications For Ecosystem Management, Charles W. Lafon, Henri D. Grissino-Mayer, Sally P. Horn, Robert N. Klein

Joint Fire Science Program Research Project Reports

Information about historic fire regimes and the departure of current fire regimes from historic conditions is essential for guiding and justifying management actions, such as prescribed burning programs for ecosystem process restoration and fuel reduction. Such information is noticeably lacking for the southern Appalachian Mountains, where human populations are encroaching onto wildland areas, and where decades of fire exclusion have contributed to the decline of fire-associated communities and also to altered fuel loads. We address this knowledge gap via a multi-scale investigation of the variability in fire regimes over time and space using tree-ring reconstructions of fire history and stand …


Fuel Consumption And Smoke Emissions From Landscape-Scale Burns In Eastern Hardwoods, Matthew Dickinson, Ann Acheson, Robert Kremens Jan 2010

Fuel Consumption And Smoke Emissions From Landscape-Scale Burns In Eastern Hardwoods, Matthew Dickinson, Ann Acheson, Robert Kremens

Joint Fire Science Program Research Project Reports

Our project used remotely-sensed infrared radiation measurements to estimate fuel consumption in eastern mixed-oak forests and facilitated the development of smoke management expertise and processes for complying with EPA regulations in Ohio and Kentucky. As a result of two workshops, Ohio developed a Smoke Management Plan designed to ensure that best management practices were being used across land ownerships and to facilitate mandated information sharing with the Ohio EPA and US EPA. Ohio also established a Prescribed Fire Council as a result of this process. Kentucky opted for a less formal response to EPA regulations, establishing a Prescribed Fire Council …


Developing And Using Fire Scar Histories In The Southern And Eastern United States, Richard P. Guyette, Martin Spetich, Daniel C. Dey Jan 2010

Developing And Using Fire Scar Histories In The Southern And Eastern United States, Richard P. Guyette, Martin Spetich, Daniel C. Dey

Joint Fire Science Program Research Project Reports

Land managers developing fire management plans in the eastern and southern United States lack quantitative information on historic fire regimes. Twelve new fire histories were developed from dated fire scars on trees from regions where no fire scar history data had existed before in the states of Alabama, Louisiana, Kentucky, Iowa, Wisconsin, and Michigan. Sites represent highly variable climates from extreme cold (with long snow cover duration) to subtropical. All sites utilized oak or pine recorder species that were collected from closed forest to open savanna structures. Pre-industrial mean fire intervals ranged from 3 to more than 35 years at …


Do Annual Prescribed Fires Enhance Or Slow The Loss Of Coastal Marsh Habitat At Blackwater National Wildlife Refuge?, Donald R. Cahoon, Glenn Guntenspergen, Suzanne Baird Jan 2010

Do Annual Prescribed Fires Enhance Or Slow The Loss Of Coastal Marsh Habitat At Blackwater National Wildlife Refuge?, Donald R. Cahoon, Glenn Guntenspergen, Suzanne Baird

Joint Fire Science Program Research Project Reports

The rate of estuarine marsh loss at Blackwater NWR has been high (up to 2,000 ha) during the past 80 years because the vertical buildup of the marsh surface has lagged behind the local rate of relative sea-level rise. In this mineral sediment-poor estuary, marsh vertical development is driven primarily by the accumulation of plant matter in the soil (roots and rhizomes). Thus any activity that affects plant productivity can affect the ability of these marshes to keep pace with sea-level rise. Blackwater NWR has employed an annual prescribed fire regime since the 1970’s to achieve multiple management objectives. However, …


Do Fuel Treatments Reduce Fire Severity? Evaluating Treatment Effectiveness In The 2006 Tripod Complex Fires, Susan J. Prichard, David L. Peterson Jan 2010

Do Fuel Treatments Reduce Fire Severity? Evaluating Treatment Effectiveness In The 2006 Tripod Complex Fires, Susan J. Prichard, David L. Peterson

Joint Fire Science Program Research Project Reports

The 2006 Tripod Complex fires burned over 70,000 ha of dry mixed conifer forests in north-central Washington State. Recent fuel treatments burned in the wildfire offered an opportunity to quantitatively evaluate if fuel treatment effectively mitigated fire severity. We quantified the relative effect of two common fuel treatments: mechanical thinning only (thin) and mechanical thinning followed by prescribed burning (thinRx). Fire severity was markedly different between the two treatments. Over 57% of trees survived in thinRx units versus 19% in thin and 14% in control units. Considering only large-diameter trees (> 20 cm dbh), 73% survived in thinRx units versus …


Effect Of Season And Interval Of Prescribed Burns In A Ponderosa Pine Ecosystem On Tree Growth And Understory Vegetation., W. G. Thies, Becky K. Kerns, Douglas J. Westlind Jan 2010

Effect Of Season And Interval Of Prescribed Burns In A Ponderosa Pine Ecosystem On Tree Growth And Understory Vegetation., W. G. Thies, Becky K. Kerns, Douglas J. Westlind

Joint Fire Science Program Research Project Reports

After decades of fire exclusion many stands now have historically unprecedented (high) levels of fuels and overstocking. As a result these stands have developed a variety of health issues. In response to these problems land managers are using prescribed fire to restore fuel loads and stand stocking to pre-fire exclusion levels. The impacts of season of prescribed burn as well as burn interval are not well understood. Managers need the ability to better predict these impacts on such things as tree mortality from fire, associated insect attack and disease development, tree growth, and plant communities. The “Season of Burn” study …


Effects Of Prescribed Burning, Mechanical, And Chemical Treatments To Curtail Rhododendron Dominance And Reduce Urban Interface Fuel Loads, Shepard M. Zedaker, Charles W. Harrell Iii, Christopher D. Pearce Jan 2010

Effects Of Prescribed Burning, Mechanical, And Chemical Treatments To Curtail Rhododendron Dominance And Reduce Urban Interface Fuel Loads, Shepard M. Zedaker, Charles W. Harrell Iii, Christopher D. Pearce

Joint Fire Science Program Research Project Reports

One-half-acre treatment areas were delineated within prescribed burns. Cutting treatments consisted of chainsaw or brushsaw severing of all rhododendron stems within 6 in of the ground surface. Herbicide and herbicide followed by fire treatments consisted of basal applications of triclopyr or imazapyr in methylated seed oil on each plot. Cutting and burning treatments followed by herbicides utilized foliar applications of triclopyr or imazapyr in emulsions to all resprouting rhododendron. All herbicide plots were randomly split in half for the application of imazapyr or triclopyr on different halves. Analyses of variance and mean separation by LSD were used to compare treatment …


Evaluating Postfire Seeding Treatments Designed To Suppress Cheatgrass (Bromus Tectorum) In A Ponderosa Pine Forest On The Colorado Plateau, Matthew L. Brooks, Robert Klinger, Jennifer Chase, Curt Deuser Jan 2010

Evaluating Postfire Seeding Treatments Designed To Suppress Cheatgrass (Bromus Tectorum) In A Ponderosa Pine Forest On The Colorado Plateau, Matthew L. Brooks, Robert Klinger, Jennifer Chase, Curt Deuser

Joint Fire Science Program Research Project Reports

The restoration of historical fuel conditions and fire regimes is one of the primary land management goals in the Shivwits Plateau region of northwestern Arizona. Fire is the primary tool used in this region to reduce fuel loads and shift landscapes back to historical conditions of a low intensity, 8- 15 year return interval, surface fire regime. However, the invasive plant cheatgrass has become the dominant understory vegetation and fuel type following initial fire treatments in many areas. There is significant concern that repeated burning at historically appropriate fire return intervals for ponderosa pine forest will benefit this invasive plant …


Evaluating Approaches To Mapping Burn Probabilities For A Quantitative Wildland Fire Risk Analysis Framework., Carol Miller, Marc Parisien, Alan Ager, Mark Finney Jan 2010

Evaluating Approaches To Mapping Burn Probabilities For A Quantitative Wildland Fire Risk Analysis Framework., Carol Miller, Marc Parisien, Alan Ager, Mark Finney

Joint Fire Science Program Research Project Reports

This final report summarizes a collaboration that brought together experts in burn probability (BP) modeling and wildland fire risk analysis to compare and evaluate BP models, and ultimately incorporate these into a risk analysis framework. The project built on and extended the work from JFSP project #01-1-1-05. This project evaluated and tested three different independent models that generate BP maps as output for their operational use in risk analysis. The project quantified the relative sensitivity of the three BP models to different inputs, enhanced our understanding of the factors that affect BP at the landscape scale, and yielded concrete improvements …


Evaluating Postfire Seeding Treatments Designed To Suppress Cheatgrass (Bromus Tectorum) In A Ponderosa Pine Forest On The Colorado Plateau, Matthew L. Brooks, Robert Klinger, Jennifer Chase, Curt Deuser Jan 2010

Evaluating Postfire Seeding Treatments Designed To Suppress Cheatgrass (Bromus Tectorum) In A Ponderosa Pine Forest On The Colorado Plateau, Matthew L. Brooks, Robert Klinger, Jennifer Chase, Curt Deuser

Joint Fire Science Program Research Project Reports

The restoration of historical fuel conditions and fire regimes is one of the primary land management goals in the Shivwits Plateau region of northwestern Arizona. Fire is the primary tool used in this region to reduce fuel loads and shift landscapes back to historical conditions of a low intensity, 8- 15 year return interval, surface fire regime. However, the invasive plant cheatgrass has become the dominant understory vegetation and fuel type following initial fire treatments in many areas. There is significant concern that repeated burning at historically appropriate fire return intervals for ponderosa pine forest will benefit this invasive plant …


The Index Of Biological Integrity And The Bootstrap: Can Random Sampling Error Affect Stream Impairment Decisions?, Christine L. Dolph, Aleksey Y. Sheshukov, Christopher J. Chizinski, Bruce Vondracek, Bruce N. Wilson Jan 2010

The Index Of Biological Integrity And The Bootstrap: Can Random Sampling Error Affect Stream Impairment Decisions?, Christine L. Dolph, Aleksey Y. Sheshukov, Christopher J. Chizinski, Bruce Vondracek, Bruce N. Wilson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

Multimetric indices, such as the Index of Biological Integrity (IBI), are increasingly used bymanagement agencies to determine whether surface water quality is impaired. However, important questions about the variability of these indices have not been thoroughly addressed in the scientific literature. In this study, we used a bootstrap approach to quantify variability associated with fish IBIs developed for streams in two Minnesota river basins. We further placed this variability into a management context by comparing it to impairment thresholds currently used in water quality determinations for Minnesota streams. We found that 95% confidence intervals ranged as high as 40 points …


The Impact Of Rare Taxa On A Fish Index Of Biotic Integrity, Haibo Wan, Christopher J. Chizinski, Christine L. Dolph, Bruce Vondracek, Bruce N. Wilson Jan 2010

The Impact Of Rare Taxa On A Fish Index Of Biotic Integrity, Haibo Wan, Christopher J. Chizinski, Christine L. Dolph, Bruce Vondracek, Bruce N. Wilson

Nebraska Cooperative Fish and Wildlife Research Unit: Staff Publications

The index of biotic integrity (IBI) is a commonly used bioassessment tool that integrates abundance and richness measures to assess water quality. In developing IBIs that are both responsive to human disturbance and resistant to natural variability and sampling error, water managersmust decide how to weigh information about rare and abundant taxa, which in turn requires an understanding of the sensitivity of indices to rare taxa. Herein, we investigated the influence of rare fish taxa (within the lower 5% of rank abundance curves) on IBI metric and total scores for stream sites in two of Minnesota’smajor river basins, the St. …


The Impact Of Conservation On The Status Of The World's Vertebrates, Michael Hoffmann, Craig Hilton-Taylor, Ariadne Angulo, Monika Böhm, Thomas M. Brooks, Stuart H. M. Butchart, Kent E. Carpenter, Janice Chanson, Beth A. Polidoro, Jonnell C. Sanciangco Jan 2010

The Impact Of Conservation On The Status Of The World's Vertebrates, Michael Hoffmann, Craig Hilton-Taylor, Ariadne Angulo, Monika Böhm, Thomas M. Brooks, Stuart H. M. Butchart, Kent E. Carpenter, Janice Chanson, Beth A. Polidoro, Jonnell C. Sanciangco

Biological Sciences Faculty Publications

Using data for 25,780 species categorized on the International Union for Conservation of Nature Red List, we present an assessment of the status of the world's vertebrates. One-fifth of species are classified as Threatened, and we show that this figure is increasing: On average, 52 species of mammals, birds, and amphibians move one category closer to extinction each year. However, this overall pattern conceals the impact of conservation successes, and we show that the rate of deterioration would have been at least one-fifth again as much in the absence of these. Nonetheless, current conservation efforts remain insufficient to offset the …


Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters Jan 2010

Carbon Dynamics In A Phragmites Australis Invaded Riparian Wetland, Steven Walters

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

Invasive plant species are widely recognized as a major threat to biodiversity and ecosystem stability. Wetland ecosystems tend to be much more susceptible to invasions because of their location on the landscape where water, nutrients, and the impacts of disturbances accumulate. Invasive plants have the ability to alter ecosystem processes and community/population dynamics. The ability of invasive plants to alter these processes can have profound economic consequences. In the United States, control of invasive wetland species alone costs approximately 155 million dollars annually. The state of Nebraska spends 2 million dollars annually controlling invasive plant species in the Platte River …


Retention, Movement, And The Biotic Response To Large Woody Debris In The Channelized Missouri River, Michael W. Archer Jan 2010

Retention, Movement, And The Biotic Response To Large Woody Debris In The Channelized Missouri River, Michael W. Archer

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

Large woody debris (LWD) is an important component of a healthy aquatic ecosystem. However, little is known about the dynamics of LWD in a large, channelized river such as the Missouri River. My objectives were to first, assess the abundance of LWD found along the channelized portion of the Missouri River. Second, I documented movement of LWD that entered the river. Lastly, using PRIMER software I analyzed what effect, if any, river segments, bend types, and LWD had on the community composition of the macroinvertebrate and fish that inhabit the river. Abundance of LWD was greater along bends that have …


Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra Jan 2010

Species Composition And Spatiotemporal Pattern Of The Seed Bank And Vegetation In Native And Degraded Florida Rosemary Scrub, Jennifer J. Navarra

Electronic Theses and Dissertations

The soil seed bank plays a dynamic role in the regeneration of plant communities after natural and anthropogenic disturbance. In this thesis, I addressed how disturbances influence the vegetation and seed bank of Florida rosemary scrub. In Chapter One I evaluated changes in species composition and spatiotemporal pattern of the vegetation and seed bank along a gradient of disturbance. During the summers and winters of 2007-2009 percent ground cover and seed bank species composition were assessed among replicates of three vegetation types subjected to minimal, moderate, and extreme anthropogenic disturbance (native rosemary scrub, degraded scrub, and agriculturally improved pasture, respectively). …


Using Landscape Genetics To Assess Population Connectivity In A Habitat Generalist, Tyler Duncan Hether Jan 2010

Using Landscape Genetics To Assess Population Connectivity In A Habitat Generalist, Tyler Duncan Hether

Electronic Theses and Dissertations

Understanding the nature of genetic variation in natural populations is an underlying theme of population genetics. In recent years population genetics has benefited from the incorporation of landscape and environmental data into pre-existing models of isolation by distance (IBD) to elucidate features influencing spatial genetic variation. Many of these landscape genetics studies have focused on populations separated by discrete barriers (e.g., mountain ridges) or species with specific habitat requirements (i.e., habitat specialists). One difficulty in using a landscape genetics approach for taxa with less stringent habitat requirements (i.e., generalists) is the lack of obvious barriers to gene flow and preference …


Riparian Conundra, David Weaver Jan 2010

Riparian Conundra, David Weaver

Conference papers and presentations

Riparian vegetation is established or restored on the basis that it physically filters and traps hillslope derived particulate nutrients in surface runoff. Whilst many studies support this conventional model of riparian function, few test this models embedded assumptions. The assumptions are that catchments are surface runoff dominated, that most surface derived nutrients are transported in particulate form, and that riparian management targets locations that will result in the greatest change in water quality. This paper reviews studies in south west Western Australia that challenge these assumptions. Plots measuring leaching and runoff of nutrients showed that 20 times more water and …


State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2010, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University Jan 2010

State Of The River Report For The Lower St. Johns River Basin, Florida: Water Quality, Fisheries, Aquatic Life, And Contaminants 2010, Environmental Protection Board, City Of Jacksonville, University Of North Florida, Jacksonville University

State of the River Report

No abstract provided.