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Articles 1 - 8 of 8

Full-Text Articles in Life Sciences

Response Of Conifer-Encroached Shrublands In The Great Basin To Prescribed Fire And Mechanical Treatments, Richard F. Miller, Jaime Ratchford, Bruce A. Roundy, Robin J. Tausch, April Hulet, Jeanne C. Chambers Sep 2014

Response Of Conifer-Encroached Shrublands In The Great Basin To Prescribed Fire And Mechanical Treatments, Richard F. Miller, Jaime Ratchford, Bruce A. Roundy, Robin J. Tausch, April Hulet, Jeanne C. Chambers

Articles

In response to the recent expansion of piñon and juniper woodlands into sagebrush-steppe communities in the northern Great Basin region, numerous conifer-removal projects have been implemented, primarily to release understory vegetation at sites having a wide range of environmental conditions. Responses to these treatments have varied from successful restoration of native plant communities to complete conversion to nonnative invasive species. To evaluate the general response of understory vegetation to tree canopy removal in conifer-encroached shrublands, we set up a region-wide study that measured treatment-induced changes in understory cover and density. Eleven study sites located across four states in the Great …


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 Sep 2014

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 …


Soil Resources Influence Vegetation And Response To Fire And Fire-Surrogate Treatments In Sagebrush-Steppe Ecosystems, Benjamin M. Rau, Jeanne C. Chambers, David A. Pyke, Bruce A. Roundy, Eugene W. Schupp, Paul Doescher, Todd G. Caldwell Sep 2014

Soil Resources Influence Vegetation And Response To Fire And Fire-Surrogate Treatments In Sagebrush-Steppe Ecosystems, Benjamin M. Rau, Jeanne C. Chambers, David A. Pyke, Bruce A. Roundy, Eugene W. Schupp, Paul Doescher, Todd G. Caldwell

Articles

Current paradigm suggests that spatial and temporal competition for resources limit an exotic invader, cheatgrass (Bromus tectorum L.), which once established, alters fire regimes and can result in annual grass dominance in sagebrush steppe. Prescribed fire and fire surrogate treatments (mowing, tebuthiuron, and imazapic) are used to reduce woody fuels and increase resistance to exotic annuals, but may alter resource availability and inadvertently favor invasive species. We used four study sites within the Sagebrush Steppe Treatment Evaluation Project (SageSTEP) to evaluate 1) how vegetation and soil resources were affected by treatment, and 2) how soil resources influenced native herbaceous …


Piñon-Juniper Reduction Increases Soil Water Availability Of The Resource Growth Pool, Bruce A. Roundy, Kert Young, Nathan Cline, April Hulet, Richard F. Miller, Robin J. Tausch, Jeanne C. Chambers, Benjamin Rau Sep 2014

Piñon-Juniper Reduction Increases Soil Water Availability Of The Resource Growth Pool, Bruce A. Roundy, Kert Young, Nathan Cline, April Hulet, Richard F. Miller, Robin J. Tausch, Jeanne C. Chambers, Benjamin Rau

Articles

Managers reduce piñon (Pinus spp.) and juniper (Juniperus spp.) trees that are encroaching on sagebrush (Artemisia spp.) communities to lower fuel loads and increase cover of desirable understory species. All plant species in these communities depend on soil water held at &spigt; -1.5 MPa matric potential in the upper 0.3 m of soil for nutrient diffusion to roots and major growth in spring (resource growth pool). We measured soil water matric potentials and temperatures using gypsum blocks and thermocouples buried at 0.01–0.3 m on tree, shrub, and interspace microsites to characterize the seasonal soil climate of 13 …


Acceptance, Acceptability, And Trust For Sagebrush Restoration Options In The Great Basin: A Longitudinal Perspective, Ryan Gordon, Mark W. Brunson, Bruce Shindler Sep 2014

Acceptance, Acceptability, And Trust For Sagebrush Restoration Options In The Great Basin: A Longitudinal Perspective, Ryan Gordon, Mark W. Brunson, Bruce Shindler

Articles

In surveys of residents in three urban and three rural locations in the Great Basin we examined the social acceptability of six management practices showing promise for restoring sagebrush-dominated rangelands. Unlike most studies of range management perceptions that have relied on single measurements, we used longitudinal data from a questionnaire mailed in 2006 to residents that were resurveyed in 2010. Overall, 698 respondents comprised the panel. Respondents' self-reported levels of knowledge about the health and management of Great Basin rangelands decreased from 2006 to 2010. In both years, mean acceptance was greater for the use of prescribed fire, grazing, felling, …


Understory Cover Responses To Piñon-Juniper Treatments Across Tree Dominance Gradients In The Great Basin, Bruce A. Roundy, Richard F. Miller, Robin J. Tausch, Kert Young, April Hulet, Benjamin Rau, Brad Jessop, Jeanne C. Chambers, Dennis Eggett Sep 2014

Understory Cover Responses To Piñon-Juniper Treatments Across Tree Dominance Gradients In The Great Basin, Bruce A. Roundy, Richard F. Miller, Robin J. Tausch, Kert Young, April Hulet, Benjamin Rau, Brad Jessop, Jeanne C. Chambers, Dennis Eggett

Articles

Piñon (Pinus spp.) and juniper (Juniperus spp.) trees are reduced to restore native vegetation and avoid severe fires where they have expanded into sagebrush (Artemisia tridentata Nutt.) communities. However, what phase of tree infilling should treatments target to retain desirable understory cover and avoid weed dominance? Prescribed fire and tree felling were applied to 8–20-ha treatment plots at 11 sites across the Great Basin with a tree-shredding treatment also applied to four Utah sites. Treatments were applied across a tree infilling gradient as quantified by a covariate tree dominance index (TDI = tree cover/[tree + shrub + …


Mechanical Mastication Of Utah Juniper Encroaching Sagebrush Steppe Increases Inorganic Soil N, Kert R. Young, Bruce A. Roundy, Dennis L. Eggett Apr 2014

Mechanical Mastication Of Utah Juniper Encroaching Sagebrush Steppe Increases Inorganic Soil N, Kert R. Young, Bruce A. Roundy, Dennis L. Eggett

Articles

Juniper (Juniperus spp.) has encroached on millions of hectares of sagebrush (Artemisia spp.) steppe. Juniper mechanical mastication increases cover of understory species but could increase resource availability and subsequently invasive plant species. We quantified the effects of juniper mastication on soil resource availability by comparing total C, total N, C : N ratio, Olsen extractable P, sulfate S, and pH using soil samples and inorganic N (NO3-+NH4+) using ion exchange membranes. We compared resource availability in paired masticated and untreated areas in three juniper-dominated sagebrush and bunchgrass ecosystems in the Utah portion …


Hydrologic And Erosion Responses To Wildfire Along The Rangeland-Xeric Forest Continuum In The Western Us: A Review And Model Of Hydrologic Vulnerability, Christopher Jason Williams, Frederick B. Pierson, Peter R. Robichaud, Jan Boll Feb 2014

Hydrologic And Erosion Responses To Wildfire Along The Rangeland-Xeric Forest Continuum In The Western Us: A Review And Model Of Hydrologic Vulnerability, Christopher Jason Williams, Frederick B. Pierson, Peter R. Robichaud, Jan Boll

Articles

The recent increase in wildfire activity across the rangeland–xeric forest continuum in the western United States has landscape-scale consequences in terms of runoff and erosion. Concomitant cheatgrass (Bromus tectorum L.) invasions, plant community transitions and a warming climate in recent decades along grassland–shrubland–woodland–xeric forest transitions have promoted frequent and large wildfires, and continuance of the trend appears likely if warming climate conditions prevail. These changes potentially increase overall hydrologic vulnerability by spatially and temporally increasing soil exposure to runoff and erosion processes. Plot and hillslope-scale studies demonstrate burning may increase event runoff or erosion by factors of 2–40 over …