Southwest Biological Science Center
Hierarchical, quantitative biogeographic provinces for all North American turtles and their contribution to the biogeography of turtles and the continent
Our study represents the first attempt to describe biogeographic provinces for North American (México, United States, and Canada) turtles. We analyzed three nested data sets separately: (1) all turtles, (2) freshwater turtles, and (3) aquatic turtles. We georeferenced North American turtle distributions, then we created presence–absence matrices...Ennen, Joshua R.; Matamoros, Wilfredo A.; Agha, Mickey; Lovich, Jeffrey E.; Sweat, Sarah C.; Hoagstrom, Christopher W.
Greenup and evapotranspiration following the Minute 319 pulse flow to Mexico: An analysis using Landsat 8 Normalized Difference Vegetation Index (NDVI) data
In the southwestern U.S., many riparian ecosystems have been altered by dams, water diversions, and other anthropogenic activities. This is particularly true of the Colorado River, where numerous dams and agricultural diversions have affected this water course, especially south of the U.S.–Mexico border. In the spring of 2014, 130 million cubic...Jarchow, Christopher J.; Nagler, Pamela L.; Glenn, Edward P.
Competition amplifies drought stress in forests across broad climatic and compositional gradients
Forests around the world are experiencing increasingly severe droughts and elevated competitive intensity due to increased tree density. However, the influence of interactions between drought and competition on forest growth remains poorly understood. Using a unique dataset of stand-scale dendrochronology sampled from 6405 trees, we quantified how...Gleason, Kelly; Bradford, John B.; Bottero, Alessandra; D'Amato, Tony; Fraver, Shawn; Palik, Brian J.; Battaglia, Michael; Iverson, Louis R.; Kenefic, Laura; Kern, Christel C.
It takes more than water: Restoring the Colorado River Delta
Environmental flows have become important tools for restoring rivers and associated riparian ecosystems (Arthington, 2012; Glenn et al., 2017). In March 2014, the United States and Mexico initiated a bold effort in restoration, delivering from Morelos Dam a “pulse flow” of water into the Colorado River in its delta for the purpose of learning...Pitt, Jennifer; Kendy, Eloise; Schlatter, Karen; Hinojosa-Huertaf, Osvel; Flessa, Karl W.; Shafroth, Patrick B.; Ramirez-Hernandez, Jorge; Nagler, Pamela L.; Glenn, Edward P.
Spatial variation in edaphic characteristics is a stronger control than nitrogen inputs in regulating soil microbial effects on a desert grass
Increased atmospheric nitrogen (N) deposition can have wide-ranging effects on plant community structure and ecosystem function, some of which may be indirectly mediated by soil microbial responses to an altered biogeochemical environment. In this study, soils from a field N fertilization experiment that spanned a soil texture gradient were used...Chung, Y. Anny; Sinsabaugh, Robert L; Kuske, Cheryl R.; Reed, Sasha C.; Rudgers, Jennifer A.
Topographic, edaphic, and vegetative controls on plant-available water
Soil moisture varies within landscapes in response to vegetative, physiographic, and climatic drivers, which makes quantifying soil moisture over time and space difficult. Nevertheless, understanding soil moisture dynamics for different ecosystems is critical, as the amount of water in a soil determines a myriad ecosystem services and processes...Dymond, Salli F.; Bradford, John B.; Bolstad, Paul V.; Kolka, Randall K.; Sebestyen, Stephen D.; DeSutter, Thomas S.
Climate and soil texture influence patterns of forb species richness and composition in big sagebrush plant communities across their spatial extent in the western US
Article for outlet: Plant Ecology. Abstract: Big sagebrush (Artemisia tridentata Nutt.) plant communities are widespread non-forested drylands in western North American and similar to all shrub steppe ecosystems world-wide are composed of a shrub overstory layer and a forb and graminoid understory layer. Forbs account for the majority of plant...Pennington, Victoria E.; Palmquist, Kyle A.; Bradford, John B.; Lauenroth, William K.
Southwest Exotic Mapping Program (SWEMP) Database, 2007
The Southwest Exotic Plant Mapping Program (SWEMP) is a collaborative effort between the United States Geological Survey and federal, tribal, state, county and non-governmental organization (NGO) partners in the southwest. This project is an ongoing effort to compile and distribute regional data on the occurrence of non-native invasive plants in...Thomas, Kathryn A.; Guertin, Patricia
Reclamation after oil and gas development does not speed up succession or plant community recovery in big sagebrush ecosystems in Wyoming
Article for intended outlet: Restoration Ecology. Abstract: Reclamation is an application of treatment(s) following a disturbance to promote succession and accelerate the return of target conditions. Previous studies have framed reclamation in the context of succession by studying its effectiveness in re-establishing late-successional plant...Rottler, Caitlin M.; Burke, Ingrid C.; Palmquist, Kyle A.; Bradford, John B.; Lauenroth, William K.
Ecohydrological role of biological soil crusts across a gradient in levels of development
Though biological soil crusts (biocrusts) form abundant covers in arid and semiarid regions, their competing effects on soil hydrologic conditions are rarely accounted for in models. This study presents the modification of a soil water balance model to account for the presence of biocrusts at different levels of development (LOD) and their impact...Whitney, Kristen M.; Vivoni, Enrique R.; Duniway, Michael C.; Bradford, John B.; Reed, Sasha C.; Belnap, Jayne
Does bioelectrical impedance analysis accurately estimate the condition of threatened and endangered desert fish species?
Bioelectrical impedance analysis (BIA) is a nonlethal tool with which to estimate the physiological condition of animals that has potential value in research on endangered species. However, the effectiveness of BIA varies by species, the methodology continues to be refined, and incidental mortality rates are unknown. Under laboratory conditions we...Dibble, Kimberly L.; Yard, Micheal D.; Ward, David L.; Yackulic, Charles B.
Biological soil crusts: Diminutive communities of potential global importance
Biological soil crusts (biocrusts) are widespread, diverse communities of cyanobacteria, fungi, lichens, and mosses living on soil surfaces, primarily in drylands. Biocrusts can locally govern primary production, soil fertility, hydrology, and surface energy balance, with considerable variation in these functions across alternate community states...Ferrenberg, Scott; Tucker, Colin; Reed, Sasha C.