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Full-Text Articles in Plant Sciences
Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Reangelands, Great Basin, Usa: Part Ii: Runoff And Sediment Transport At The Patch Scale, Sayjro K. Nouwakpo, Christopher Jason Williams, Frederick B. Pierson, Mark A. Weltz, Patrick R. Kormos, Osama Z. Al-Hamdan
Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Reangelands, Great Basin, Usa: Part Ii: Runoff And Sediment Transport At The Patch Scale, Sayjro K. Nouwakpo, Christopher Jason Williams, Frederick B. Pierson, Mark A. Weltz, Patrick R. Kormos, Osama Z. Al-Hamdan
Articles
Woody species encroachment into herbaceous and shrub-dominated vegetations is a concern in many rangeland ecosystems of the world. Arrival of woody species into affected rangelands leads to changes in the spatial structure of vegetation and alterations of biophysical processes. In the western USA, encroachment of pinyon (Pinus spp.) and juniper (Juniperus spp.) tree species into sagebrush steppes poses a threat to the proper ecohydrological functioning of these ecosystems. Prescribed fire has been proposed and used as one rangeland improvement practice to restore sagebrush steppe from pinyon-juniper encroachment. Short-term effects of burning on the ecohydrologic response of these systems …
Long-Term Evidence For Fire As An Ecohydrologic Threshold-Reversal Mechanism On Woodland-Encroached Sagebrush Shrublands, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Patrick R. Kormos, Osama Z. Al-Hamdan, Mark A. Weltz
Long-Term Evidence For Fire As An Ecohydrologic Threshold-Reversal Mechanism On Woodland-Encroached Sagebrush Shrublands, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Patrick R. Kormos, Osama Z. Al-Hamdan, Mark A. Weltz
Articles
Encroachment of sagebrush (Artemisia spp.) shrublands by pinyon (Pinus spp.) and juniper (Juniperus spp.) conifers (woodland encroachment) induces a shift from biotic‐controlled resource retention to abiotic‐driven loss of soil resources. This shift is driven by a coarsening of the vegetation structure with increasing dominance of site resources by trees. Competition between the encroaching trees and understory vegetation for limited soil and water resources facilitates extensive bare intercanopy area between trees and concomitant increases in run‐off and erosion that, over time, propagate persistence of the shrubland‐to‐woodland conversion. We evaluated whether tree removal by burning can decrease late‐succession woodland …
Vegetation, Hydrologic, And Erosion Responses Of Sagebrush Steppe 9 Yr Following Mechanical Tree Removal, Christopher Jason Williams, Frederick B. Pierson, Patrick R. Kormos, Osama Z. Al-Hamdan, Sayjro K. Nouwakpo, Mark A. Weltz
Vegetation, Hydrologic, And Erosion Responses Of Sagebrush Steppe 9 Yr Following Mechanical Tree Removal, Christopher Jason Williams, Frederick B. Pierson, Patrick R. Kormos, Osama Z. Al-Hamdan, Sayjro K. Nouwakpo, Mark A. Weltz
Articles
Land managers across the western United States are faced with selecting and applying tree-removal treatments on pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland-encroached sagebrush (Artemisia spp.) rangelands, but current understanding of long-term vegetation and hydrological responses of sagebrush sites to tree removal is inadequate for guiding management. This study applied a suite of vegetation and soil measures (0.5 − 990 m2), small-plot rainfall simulations (0.5 m2), and overland flow experiments (9 m2) to quantify the effects of mechanical tree removal (tree cutting and mastication) on vegetation, runoff, and erosion at …
Innovation In Rangeland Monitoring: Annual, 30 M, Plant Functional Type Percent Cover Maps For U.S. Rangelands, 1984-2017, Matthew O. Jones, Brady W. Allred, David E. Naugle, Jeremy D. Maestas, Patrick Donnelly, Loretta J. Metz, Jason Karl, Rob Smith, Brandon Bestelmeyer, Chad Boyd, Jay D. Kerby, James D. Mciver
Innovation In Rangeland Monitoring: Annual, 30 M, Plant Functional Type Percent Cover Maps For U.S. Rangelands, 1984-2017, Matthew O. Jones, Brady W. Allred, David E. Naugle, Jeremy D. Maestas, Patrick Donnelly, Loretta J. Metz, Jason Karl, Rob Smith, Brandon Bestelmeyer, Chad Boyd, Jay D. Kerby, James D. Mciver
Articles
Innovations in machine learning and cloud‐based computing were merged with historical remote sensing and field data to provide the first moderate resolution, annual, percent cover maps of plant functional types across rangeland ecosystems to effectively and efficiently respond to pressing challenges facing conservation of biodiversity and ecosystem services. We utilized the historical Landsat satellite record, gridded meteorology, abiotic land surface data, and over 30,000 field plots within a Random Forests model to predict per‐pixel percent cover of annual forbs and grasses, perennial forbs and grasses, shrubs, and bare ground over the western United States from 1984 to 2017. Results were …
Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Rangelands, Great Basin, Usa: Part I: Vegetation, Hydrology, And Erosion Responses, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Osama Z. Al-Hamdan, Patrick R. Kormos, Mark A. Weltz
Effectiveness Of Prescribed Fire To Re-Establish Sagebrush Steppe Vegetation And Ecohydrologic Function On Woodland-Encroached Sagebrush Rangelands, Great Basin, Usa: Part I: Vegetation, Hydrology, And Erosion Responses, Christopher Jason Williams, Frederick B. Pierson, Sayjro K. Nouwakpo, Osama Z. Al-Hamdan, Patrick R. Kormos, Mark A. Weltz
Articles
Pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland encroachment has imperiled a broad ecological domain of the sagebrush steppe (Artemisia spp.) ecosystem in the Great Basin Region, USA. As these conifers increase in dominance on sagebrush rangelands, understory vegetation declines and ecohydrologic function can shift from biotic (vegetation) controlled retention of soil resources to abiotic (runoff) driven loss of soil resources and long-term site degradation. Scientists, public land management agencies, and private land owners are challenged with selecting and predicting outcomes to treatment alternatives to improve ecological structure and function on these rangelands. This study is the …
Influence Of Harvest Date On Seed Yield And Quality In Forage Kochia, Cody F. Creech, Blair L. Waldron, Corey V. Ransom, Dale R. Zobell, Joseph Earl Creech
Influence Of Harvest Date On Seed Yield And Quality In Forage Kochia, Cody F. Creech, Blair L. Waldron, Corey V. Ransom, Dale R. Zobell, Joseph Earl Creech
Plants, Soils, and Climate Faculty Publications
Forage kochia (Bassia prostrata) is used for rangeland reclamation and livestock and wildlife forage, but limited research has been conducted on its seed production. Therefore, this research evaluated the effect of harvest date on seed weight, germination, and seed yield of forage kochia subspecies virescens and grisea. Seed was harvested from individual plants for 3 years during October, November, and December. October harvest had the lightest 100-seed weights, with the November harvest slightly heavier than December, for most accessions. Cultivar Snowstorm and breeding line Sahsel, both subsp. grisea, had the greatest 100-seed weights in November, 155 …
Herbivory And Drought Generate Short‐Term Stochasticity And Long‐Term Stability In A Savanna Understory Community, Corinna Riginos, Lauren M. Porensky, Kari E. Veblen, Truman P. Young
Herbivory And Drought Generate Short‐Term Stochasticity And Long‐Term Stability In A Savanna Understory Community, Corinna Riginos, Lauren M. Porensky, Kari E. Veblen, Truman P. Young
Wildland Resources Faculty Publications
Rainfall and herbivory are fundamental drivers of grassland plant dynamics, yet few studies have examined long‐term interactions between these factors in an experimental setting. Understanding such interactions is important, as rainfall is becoming increasingly erratic and native wild herbivores are being replaced by livestock. Livestock grazing and episodic low rainfall are thought to interact, leading to greater community change than either factor alone. We examined patterns of change and stability in herbaceous community composition through four dry periods, or droughts, over 15 years of the Kenya Long‐term Exclosure Experiment (KLEE), which consists of six different combinations of cattle, native wild …
Salinity Tolerance Of Three Competing Rangeland Plant Species: Studies In Hydroponic Culture, Joseph K. Sagers, Blair L. Waldrom, Joseph Earl Creech, Ivan W. Mott, Bruce Bugbee
Salinity Tolerance Of Three Competing Rangeland Plant Species: Studies In Hydroponic Culture, Joseph K. Sagers, Blair L. Waldrom, Joseph Earl Creech, Ivan W. Mott, Bruce Bugbee
Plants, Soils, and Climate Faculty Publications
Halogeton (Halogeton glomeratus) is an invasive species that displaces Gardner's saltbush (Atriplex gardneri) on saline rangelands, whereas, forage kochia (Bassia prostrata) potentially can rehabilitate these ecosystems. Salinity tolerance has been hypothesized as the predominant factor affecting frequency of these species. This study compared relative salinity tolerance of these species, and tall wheatgrass (Thinopyrum ponticum) and alfalfa (Medicago sativa). Plants were evaluated in hydroponics, eliminating the confounding effects of drought, for 28 days at 0, 150, 200, 300, 400, 600, and 800 mmol/L NaCl. Survival, growth, and ion accumulation were determined. …
Incorporating Hydrologic Data And Ecohydrologic Relationships Into Ecological Site Descriptions, Christopher Jason Williams, Frederick B. Pierson, Kenneth E. Spaeth, Joel R. Brown, Osama Z. Al-Hamdan, Mark A. Weltz, Mark A. Nearing, Jeffrey E. Herrick, Jan Boll, Peter R. Robichaud, David C. Goodrich, Phillip Heilman, D. Phillip Guertin, Mariano Hernandez, Haiyan Wei, Stuart P. Hardegree, Eva K. Strand, Jonathan D. Bates, Loretta J. Metz, Mary H. Nichols
Incorporating Hydrologic Data And Ecohydrologic Relationships Into Ecological Site Descriptions, Christopher Jason Williams, Frederick B. Pierson, Kenneth E. Spaeth, Joel R. Brown, Osama Z. Al-Hamdan, Mark A. Weltz, Mark A. Nearing, Jeffrey E. Herrick, Jan Boll, Peter R. Robichaud, David C. Goodrich, Phillip Heilman, D. Phillip Guertin, Mariano Hernandez, Haiyan Wei, Stuart P. Hardegree, Eva K. Strand, Jonathan D. Bates, Loretta J. Metz, Mary H. Nichols
Articles
The purpose of this paper is to recommend a framework and methodology for incorporating hydrologic data and ecohydrologic relationships in Ecological Site Descriptions (ESDs) and thereby enhance the utility of ESDs for assessing rangelands and guiding resilience-based management strategies. Resilience-based strategies assess and manage ecological state dynamics that affect state vulnerability and, therefore, provide opportunities to adapt management. Many rangelands are spatially heterogeneous or sparsely vegetated where the vegetation structure strongly influences infiltration and soil retention. Infiltration and soil retention further influence soil water recharge, nutrient availability, and overall plant productivity. These key ecohydrologic relationships govern the ecologic resilience of …
Short-Term Effects Of Tree Removal On Infiltration, Runoff, And Erosion In Woodland-Encroached Sagebrush Steppe, Frederick B. Pierson, Christopher Jason Williams, Patrick R. Kormos, Osama Z. Al-Hamdan
Short-Term Effects Of Tree Removal On Infiltration, Runoff, And Erosion In Woodland-Encroached Sagebrush Steppe, Frederick B. Pierson, Christopher Jason Williams, Patrick R. Kormos, Osama Z. Al-Hamdan
Articles
Land owners and managers across the western United States are increasingly searching for methods to evaluate and mitigate the effects of woodland encroachment on sagebrush steppe ecosystems. We used small-plot scale (0.5 m2) rainfall simulations and measures of vegetation, ground cover, and soils to investigate woodland response to tree removal (prescribed fire and mastication) at two late-succession woodlands. We also evaluated the effects of burning on soil water repellency and effectiveness of aggregate stability indices to detect changes in erosion potential. Plots were located in interspaces between tree and shrub canopies and on undercanopy tree and shrub microsites. Erosion from …
Risk Assessment Of Erosion From Concentrated Flow On Rangelands Using Overland Flow Distribution And Shear Stress Partitioning, Osama Z. Al-Hamdan, Frederick B. Pierson, Mark A. Nearing, Christopher Jason Williams, Jeffry J. Stone, Patrick R. Kormos, Jan Boll, Mark A. Weltz
Risk Assessment Of Erosion From Concentrated Flow On Rangelands Using Overland Flow Distribution And Shear Stress Partitioning, Osama Z. Al-Hamdan, Frederick B. Pierson, Mark A. Nearing, Christopher Jason Williams, Jeffry J. Stone, Patrick R. Kormos, Jan Boll, Mark A. Weltz
Articles
Erosion rates of overland flow on rangelands tend to be relatively low, but under certain conditions where flow is concentrated, soil loss can be significant. Therefore, a rangeland site can be highly vulnerable to soil erosion where overland flow is likely to concentrate and exert high shear stress on soil grains. This concept is commonly applied in cropland and wildland soil erosion modeling using predictions of flow effective shear stress (shear stress applied on soil grains). However, historical approaches to partition shear stress in erosion models are computationally complex and require extensive parameterization. Furthermore, most models are not capable of …
Sagebrush Steppe Treatment Evaluation Project (Sagestep): Restoration Research With Practical Applications, Summer Olsen
Sagebrush Steppe Treatment Evaluation Project (Sagestep): Restoration Research With Practical Applications, Summer Olsen
Articles
Sagebrush rangelands cover millions of acres in the Great Basin including parts of Oregon, California, Idaho, Nevada, and Utah. This land provides a variety of important services, including wildlife habitat, clean water, recreation, and economic opportunities; it also serves as the primary forage base for the western livestock industry. Healthy sagebrush rangelands are rapidly being lost due to a variety of factors including severe wildfires, woodland expansion, invasion of non-native species, urban development, and drought. This loss can have significant impacts on those who depend on the land for goods and services.
Rangeland Fires And Cheatgrass: Values At Risk And Support For Preservation, M. D. R. Evans, Kim Rollins
Rangeland Fires And Cheatgrass: Values At Risk And Support For Preservation, M. D. R. Evans, Kim Rollins
Articles
The high desert sagebrush ecosystems of the Great Basin evolved with fire. However, the introduction of cheatgrass (t. bromus), a highly flammable invasive annual grass, has contributed to the increased intensity and frequency of wildfires we have seen in recent years. Cheatgrass-fueled fires often kill native perennials, which creates openings for further cheatgrass expansion. Winters with more moisture than usual result in more cheatgrass and increased fire risk. Over time the result is ever larger areas dominated by cheatgrass and other invasive weeds that burn with greater frequency, and increasingly severe fire seasons.
Public Priorities For Rangeland Management: A Regional Survey Of Citizens In The Great Basin, Bruce Shindler, Ryan Gordon, Mark W. Brunson
Public Priorities For Rangeland Management: A Regional Survey Of Citizens In The Great Basin, Bruce Shindler, Ryan Gordon, Mark W. Brunson
Reports
Healthy sagebrush communities in the Great Basin are rapidly disappearing due to invasion of non-native plants, catastrophic wildfires, and encroachment of pinyon-juniper woodlands. Land management options, including the use of prescribed fire, mechanical thinning, and herbicides can reduce the potential for wildfire and restore healthy plant communities. Public acceptance of management actions is a critical component of developing and implementing successful long-term land management plans. This study examined citizens' opinions and perceptions about rangeland management in the Great Basin.
The 2005 Nevada Rangeland Vegetation Survey General Public Questionnaire And Survey Of Responses, Kimberly Rollins, Anita Castledine, Sherman Swanson, M. D. R. Evans, Kent Mcadoo, Brad Schultz, Michael Havercamp, Robert Wilson
The 2005 Nevada Rangeland Vegetation Survey General Public Questionnaire And Survey Of Responses, Kimberly Rollins, Anita Castledine, Sherman Swanson, M. D. R. Evans, Kent Mcadoo, Brad Schultz, Michael Havercamp, Robert Wilson
Reports
The 2005 Nevada Rangeland Vegetation Survey was conducted as a collaborative effort between the University of Nevada, Reno (UNR) Department of Resource Economics and the University of Nevada Cooperative Extension (UNCE) Natural Resources Program to fulfill two roles.
Western Rangeland Noxious Weeds: Collecting, Sharing And Using Information, U.S. Department Of The Interior, Usda, Charles Valentine Riley Memorial Foundation
Western Rangeland Noxious Weeds: Collecting, Sharing And Using Information, U.S. Department Of The Interior, Usda, Charles Valentine Riley Memorial Foundation
All U.S. Government Documents (Utah Regional Depository)
Western rangeland weeds such as yellow starthistle, leafy spurge, Canada thistle and Russian knapweed are causing tremendous losses to agricultural industries including both crop and livestock production. Concurrently, many public lands managed by federal agencies are being steadily invaded. As a result, these lands held in the public trust are experiencing reductions in commodity yields, recreational opportunities, biodiversity and ecosystem function. Consequently, every state in the West has noxious weed management programs that endeavor to enhance the financial and technical resources available for weed management and to assist in coordination across the diverse public and private land ownership mosaic common …