Publications
Below are publications associated with the Southwest Biological Science Center's research.
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Filter Total Items: 1332
Spatiotemporal patterns of cheatgrass invasion in Colorado Plateau National Parks
Exotic annual grasses are transforming native arid and semi-arid ecosystems globally by accelerating fire cycles that drive vegetation state changes. Cheatgrass (Bromus tectorum), a particularly widespread and aggressive exotic annual grass, is a key management target in national parks of the western United States due to its impacts on wildfire and biodiversity loss. Cheatgrass is known for its hi
Authors
Tara B.B. Bishop, Seth M. Munson, Richard Gill, Jayne Belnap, Samuel B. St. Clair, Steven L. Petersen
Establishing an Agassiz’s Desert Tortoise monitoring program within the Coachella Valley multiple species habitat conservation plan area: Final report to the Coachella Valley conservation commission on work performed near the Orocopia Mountains
In support of the goals of the Coachella Valley Multiple Species Habitat Conservation Plan and Natural Community Conservation Plan (CVMSHCP/NCCP), a population of Agassiz’s desert tortoises (Gopherus agassizii) was marked and studied to establish a desert tortoise monitoring program near the Orocopia Mountains beginning in early 2017 and ending in the summer of 2018, following the epic drought of
Authors
Jeffrey E. Lovich, Shellie R. Puffer, Kristy L. Cummings
Hydrologic function of rapidly induced biocrusts
In dryland ecosystems, land degradation and erosion pose severe threats to ecosystem productivity and human wellbeing. Bio‐inoculation of degraded soils with native biological soil crusts ('biocrusts') is a promising yet relatively untested means to improve soil stability and hydrologic function (i.e. increase infiltration and reduce runoff). In a degraded semi‐arid grassland on the Colorado Plate
Authors
Stephen E. Fick, Nichole N. Barger, Michael C. Duniway
Relative prediction intervals reveal larger uncertainty in 3D approaches to predictive digital soil mapping of soil properties with legacy data
Fine scale maps of soil properties enable efficient land management and inform earth system models. Recent efforts to create soil property maps from field observations tend to use similar tree-based machine learning interpolation approaches, but often deal with depth of predictions, validation, and uncertainty differently. One of the main differences in approaches is whether to model individual de
Authors
Travis Nauman, Michael C. Duniway
Patterns of primary production and ecological drought in Yellowstone
Introduction: Photosynthesis converts sunlight into stored energy in millions of leaves, flowers and seeds that maintain the web of life in Yellowstone. This transformation of energy fixes carbon, supplies organic matter to soils, and can become fuel for wildfire. As the first link of the food chain, new plant biomass is called primary production and provides energy to consumers, including wildli
Authors
David P. Thoma, Seth Munson, Ann W. Rodman, Roy Renkin, Heidi M. Anderson, Stephanie D. Wacker
Assessing rangeland health under climate variability and change
RANGELAND HEALTH IN A CHANGING WORLD Rangeland health is an integrated metric that describes a complex suite of ecosystem properties and processes as applied to resource management. While the concept of “healthy” landscapes has a long history, the term “rangeland health” was codified in the US in 1994 as part of an effort to move towards a national, data driven, rangeland condition assessment (Nat
Authors
John B. Bradford, Michael C. Duniway, Seth M. Munson
Effects of high-flow experiments on other resources: Recreation and hydropower
Glen Canyon National Recreation Area (GCNRA) and Grand Canyon National Park (GCNP) offer unique recreational opportunities. An objective in the Long-Term Experimental and Management Plan Environmental Impact Statement (LTEMP EIS) is to maintain and improve the quality of recreational experiences (U.S. Department of the Interior, 2016). Some of the higher valued recreational activities include day-
Authors
Lucas S. Bair
Sandbar deposition caused by high-flow experiments on the Colorado River downstream from Glen Canyon Dam: November 2012 – November 2018
The streamflow regime and sand supply of the Colorado River have been affected by the presence and operations of Glen Canyon Dam since filling of Lake Powell began in March 1963. Consequent changes in river morphology have included decreases in the size and abundance of sandbars used as campsites in Grand Canyon National Park (Dolan and others, 1974; Schmidt and Graf, 1990; Kearsley and others, 19
Authors
Paul Grams
Effects of high flow experiments on riparian vegetation resources in Grand Canyon
Flood events have historically had a strong impact on riparian vegetation within Grand Canyon. Pre-dam sandbars were nearly devoid of perennial riparian vegetation due to the magnitude and frequency of periodic floods (Turner and Karpiscak, 1980). Vegetation has increased since dam closure (Waring, 1995), particularly since the early 1990s (Sankey and others, 2015). This increase in vegetation is
Authors
B.J. Butterfield, Emily C. Palmquist, Joel B. Sankey
High elevation sand/cultural Sites: The response of source-bordering aeolian dunefields to the 2012-2016 high flow experiments of the Colorado River in Grand Canyon (Extended Abstract)
Glen Canyon Dam has reduced downstream sediment supply to the Colorado River by about 95% in the reach upstream of the Little Colorado River confluence and by about 85% below the confluence (Topping and others, 2000). Operation of the dam for hydropower generation has additionally altered the flow regime of the river in Grand Canyon, largely eliminating pre-dam low flows (i.e., below 8,000 ft3/s)
Authors
Joel B. Sankey
Optimal timing of high-flow experiments for sandbar deposition
Sediment-transport theory and field measurements indicate that the greatest or most efficient deposition of sand in eddies occurs during controlled floods (a.k.a. High-Flow Experiments or HFEs) when the greatest amount of the finest sand is available on the bed of the Colorado River (Topping and others, 2010). Conducting HFEs when the sand on the bed of the Colorado River is depleted and coarse ca
Authors
David Topping, Paul E. Grams, Ronald E. Griffiths, Joseph E. Hazel, Matthew Kaplinski, David Dean, Nicholas Voichick, Joel Unema, Thomas A. Sabol
Effects of high flow experiments on warm-water native and nonnative fishes
The harsh environmental conditions and extreme flooding that created Grand Canyon also shaped the unique native fish that evolved in the Colorado River. Native fish have evolved their physiology, morphology and behavior to withstand high flood events. Flooding has been shown to benefit spawning, survival and recruitment of juvenile native fishes in many southwestern rivers. Annual pre-dam flooding
Authors
David Ward