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Long‐Term Effects Of Tree Expansion And Reduction On Soil Climate In A Semiarid Ecosystem, Bruce A. Roundy, R. F. Miller, R. J. Tausch, J. C. Chambers, B. M. Rau
Long‐Term Effects Of Tree Expansion And Reduction On Soil Climate In A Semiarid Ecosystem, Bruce A. Roundy, R. F. Miller, R. J. Tausch, J. C. Chambers, B. M. Rau
Articles
In sagebrush ecosystems, pinyon and juniper tree expansion reduces water available to perennial shrubs and herbs. We measured soil water matric potential and temperatures at 13–30 and 50–65 cm soil depths in untreated and treated plots across a range of environmental conditions. We sought to determine the effects of tree expansion, tree reduction treatments, and expansion phase at time of treatment over 12–13 yr post‐treatment. Because the effects of tree reduction on vegetation can vary with the soil temperature/moisture regime, we also analyzed differences in soil climate variables between the mesic/aridic‐xeric and frigid/xeric regime classifications for our sites. Growing conditions …
Long-Term Effectiveness Of Tree Removal To Re-Establish Sagebrush Steppe Vegetation And Associated Spatial Patterns In Surface Conditions And Soil Hydrologic Properties, C. Jason Williams, Justin C. Johnson, Frederick B. Pierson, Cameron S. Burleson, Viktor O. Polyakov, Patrick R. Kormos, S. Kossi Nouwakpo
Long-Term Effectiveness Of Tree Removal To Re-Establish Sagebrush Steppe Vegetation And Associated Spatial Patterns In Surface Conditions And Soil Hydrologic Properties, C. Jason Williams, Justin C. Johnson, Frederick B. Pierson, Cameron S. Burleson, Viktor O. Polyakov, Patrick R. Kormos, S. Kossi Nouwakpo
Articles
Pinyon (Pinus spp.) and juniper (Juniperus spp.) woodland encroachment into sagebrush (Artemisia spp.) steppe communities throughout western North America has substantially altered the vegetation structure and hydrologic function of one of the most ecologically important rangeland ecosystems in the world. Various pinyon and juniper tree removal practices are employed to re-establish sagebrush steppe vegetation and an associated resource-conserving ecohydrologic function. The effectiveness of these practices is highly variable owing to the vast domain in which woodland encroachment occurs, climate fluctuations, differences in treatment applications, and myriads of pre-treatment conditions and post-treatment land uses. This study evaluated the …
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 …
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 …
Developing A Parameterization Approach For Soil Erodibility For The Rangeland Hydrology And Erosion Model (Rhem), Osama Z. Al-Hamdan, Frederick B. Pierson, Mark A. Nearing, Christopher Jason Williams, Mariano Hernandez, Jan Boll, Sayjro K. Nouwakpo, Mark A. Weltz, Kenneth Spaeth
Developing A Parameterization Approach For Soil Erodibility For The Rangeland Hydrology And Erosion Model (Rhem), Osama Z. Al-Hamdan, Frederick B. Pierson, Mark A. Nearing, Christopher Jason Williams, Mariano Hernandez, Jan Boll, Sayjro K. Nouwakpo, Mark A. Weltz, Kenneth Spaeth
Articles
Soil erodibility is a key factor for estimating soil erosion using physically based models. In this study, a new parameterization approach for estimating erodibility was developed for the Rangeland Hydrology and Erosion Model (RHEM). The approach uses empirical equations that were developed by applying piecewise regression analysis to predict the differences of erodibility before and after disturbance (i.e., wildfire, prescribed fire, and tree encroachment) and across a wide range of soil textures as a function of vegetation cover and surface slope angle. The approach combines rain splash, sheet flow, and concentrated flow erodibilities into a single parameter for modeling erodibility …
Utah Juniper And Two-Needle Piñon Reduction Alters Fuel Loads, Kert R. Young, Bruce A. Roundy, Stephen C. Bunting, Dennis L. Eggett
Utah Juniper And Two-Needle Piñon Reduction Alters Fuel Loads, Kert R. Young, Bruce A. Roundy, Stephen C. Bunting, Dennis L. Eggett
Articles
Juniper (Juniperus spp.) and piñon (Pinus spp.) trees have encroached millions of hectares of sagebrush (Artemisia spp.)–bunchgrass communities. Juniper–piñon trees are treated to reduce canopy fuel loads and crown fire potential. We measured the effects of juniper–piñon infilling and fuel-reduction treatments on fuel load characteristics at four locations in Utah. At each location, treatment areas were burned, left untreated, or trees were cut or masticated in a randomised complete-block design. We measured standing and downed fuels by size and type along 30-m transects on 15 subplots (30 × 33 m) per location before and 1–3 years after …
Region-Wide Ecological Responses Of Arid Wyoming Big Sagebrush Communities To Fuel Treatments, David A. Pyke, Scott E. Shaff, Andrew I. Lindgren, Eugene W. Schupp, Paul S. Doescher, Jeanne C. Chambers, Jeffrey S. Burnham, Manuela M. Huso
Region-Wide Ecological Responses Of Arid Wyoming Big Sagebrush Communities To Fuel Treatments, David A. Pyke, Scott E. Shaff, Andrew I. Lindgren, Eugene W. Schupp, Paul S. Doescher, Jeanne C. Chambers, Jeffrey S. Burnham, Manuela M. Huso
Articles
If arid sagebrush ecosystems lack resilience to disturbances or resistance to annual invasives, then alternative successional states dominated by annual invasives, especially cheatgrass (Bromus tectorum L.), are likely after fuel treatments. We identified six Wyoming big sagebrush (Artemisia tridentata ssp. wyomingensis Beetle & Young) locations (152–381 mm precipitation) that we believed had sufficient resilience and resistance for recovery. We examined impacts of woody fuel reduction (fire, mowing, the herbicide tebuthiuron, and untreated controls, all with and without the herbicide imazapic) on short-term dominance of plant groups and on important land health parameters with the use of analysis of …
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.