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Publications

Below are publications associated with the Southwest Biological Science Center's research.

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Filter Total Items: 1332

Gopherus Agassizii (Agassiz’s Desert Tortoise). Overwinter movement

No abstract available.
Authors
Kristy L. Cummings, Jeffrey E. Lovich, Shellie R. Puffer

Supporting the development and use of native plant materials for restoration on the Colorado Plateau (Fiscal Year 2020 Report)

A primary focus of the Colorado Plateau Native Plant Program (CPNPP) is to identify and develop appropriate native plant materials (NPMs) for current and future restoration projects. Multiple efforts have characterized the myriad challenges inherent in providing appropriate seed resources to enable effective, widespread restoration and have identified a broad suite of research activities to provid
Authors
Robert Massatti, Daniel E. Winkler, Sasha C. Reed, Michael C. Duniway, Seth M. Munson, John B. Bradford

Riparian area changes in greenness and water use on the Lower Colorado River in the USA from 2000-2020

Declines in riparian ecosystem greenness and water use have been observed in the delta of the Lower Colorado River (LCR) since 2000. The purpose of our case study was to measure these metrics on the U.S. side of the border between Hoover and Morelos Dams to see if declining greenness was unique to the portion of the river in Mexico. In this case study, five riparian reaches of the LCR from Hoover
Authors
Pamela L. Nagler, Armando Barreto-Muñoz, Sattar Chavoshi Borujeni, Hamideh Nouri, Christopher J. Jarchow, Kamel Didan

Regional ensemble modeling reduces uncertainty for digital soil mapping

Recent country and continental-scale digital soil mapping efforts have used a single model to predict soil properties across large regions. However, different ecophysiographic regions within large-extent areas are likely to have different soil-landscape relationships so models built specifically for these regions may more accurately capture these relationships relative to a ‘global’ model. We ask
Authors
Colby C. Brungard, Travis W. Nauman, Michael C. Duniway, Kari E. Veblen, Kyle C. Nehring, David S. White, Shawn W. Salley, Julius Anchang

Preliminary assessment of carbon and nitrogen sequestration potential of wildfire-derived sediments stored by erosion control structures in forest ecosystems, southwest USA

The role of pyrogenic carbon (PyC) in the global carbon cycle is still incompletely characterized. Much work has been done to characterize PyC on landforms and in soils where it originates or in “terminal” reservoirs such as marine sediments. Less is known about intermediate reservoirs such as streams and rivers, and few studies have characterized hillslope and in-stream erosion control structures
Authors
James B. Callegary, Laura M. Norman, Christopher J. Eastoe, Joel B. Sankey, Ann Youberg

Brood provisioning rates and fledgling behavior of Cordilleran Flycatchers in southwestern Colorado

The behavior of young songbirds after fledging is one of the least understood phases of the breeding cycle, although parental provisioning rates and movement of fledglings are key to understanding life history evolution. We studied Cordilleran Flycatchers (Empidonax occidentalis) at two sites in southwestern Colorado, USA, from 2012 to 2017. We banded and sexed breeding adults to determine the rel
Authors
Abigail J. Darrah, Charles van Riper

Drivers of methane flux differ between lakes and reservoirs, complicating global upscaling efforts

Methane is an important greenhouse gas with growing atmospheric concentrations. Freshwater lakes and reservoirs contribute substantially to atmospheric methane concentrations, but the magnitude of this contribution is poorly constrained. Uncertainty stems partially from whether the sites currently sampled represent the global population as well as incomplete knowledge of which environmental variab
Authors
Bridget Deemer, Meredith A. Holgerson

A roadmap for sampling and scaling biological nitrogen fixation in terrestrial ecosystems

Accurately quantifying rates and patterns of biological nitrogen fixation (BNF) in terrestrial ecosystems is essential to characterize ecological and biogeochemical interactions, identify mechanistic controls, improve BNF representation in conceptual and numerical modelling, and forecast nitrogen limitation constraints on future carbon (C) cycling.While many resources address the technical advanta
Authors
Fiona M. Soper, Benton Taylor, Joy Winbourne, Michelle Wong, Katherine A Dynarski, Carla R. G. Reis, Mark Peoples, Cory Cleveland, Sasha C. Reed, Duncan Menge, Steven Perakis

‘Unscrambling’ the drivers of egg production in Agassiz’s desert tortoise: Climate and individual attributes predict reproductive output

ABSTRACT: The ‘bet hedging’ life history strategy of long-lived iteroparous species reduces short-term reproductive output to minimize the risk of reproductive failure over a lifetime. For desert-dwelling ectotherms living in variable and unpredictable environments, reproductive output is further influenced by precipitation and temperature via effects on food availability and limits on activity. W
Authors
Corey I. Mitchell, Derek Friend, Lauren T. Phillips, Elizabeth A. Hunter, Jeffrey E. Lovich, Mickey Agha, Shellie R. Puffer, Kristy L. Cummings, Philip A. Medica, Todd C. Esque, Kenneth E. Nussear, Kevin T. Shoemaker

UAV-based estimate of snow cover dynamics: Optimizing semi-arid forest structure for snow persistence

Seasonal snow cover in the dry forests of the American West provides essential water resources to both human and natural systems. The structure of trees and their arrangement across the landscape are important drivers of snow cover distribution across these forests, varying widely in both space and time. We used unmanned aerial vehicle (UAV) multispectral imagery and Structure-from-Motion (SfM) mo
Authors
Adam Belmonte, Temuulen T. Sankey, Joel Biedermann, John B. Bradford, Scott J Goetz, Thomas Kolb

Monitoring Tamarix changes using WorldView-2 satellite imagery in Grand Canyon National Park, Arizona

Remote sensing methods are commonly used to monitor the invasive riparian shrub tamarisk (Tamarix spp.) and its response to the northern tamarisk beetle (D. carinulata), a specialized herbivore introduced as a biocontrol agent to control tamarisk in the Southwest USA in 2001. We use a Spectral Angle Mapper (SAM) supervised classification method with WorldView-2 (2 m spatial resolution) multispectr
Authors
Nathaniel D. Bransky, Temuulen T. Sankey, Joel B. Sankey, Matthew D. Johnson, Levi R. Jamison

Response to ‘Stochastic and deterministic interpretation of pool models’

We concur with Azizi‐Rad et al. (2021) that it is vital to critically evaluate and compare different soil carbon models, and we welcome the opportunity to further describe the unique contribution of the PROMISE model (Waring et al. 2020) to this literature. The PROMISE framework does share many features with established biogeochemical models, as our original manuscript highlighted in Table 1, and
Authors
Bonnie G. Waring, Benjamin N. Sulman, Sasha C. Reed, A. Peyton Smith, Colin Averill, Courtney Creamer, Daniela F. Cusack, Steven J. Hall, Julie D. Jastrow, Andrea Jilling, Kenneth M. Kemner, Markus Kleber, Xiao-Jun Allen Liu, Jennifer Pett-Ridge, Marjorie S. Schulz