John B Bradford, Ph.D.
John Bradford is a Research Ecologist with the USGS Northwest Climate Adaptation Science Center. John studies dryland ecosystems in the context of global change and works with resource managers to identify adaptive strategies for sustaining these ecosystems in a changing world.
John focuses on understanding how changing climate, disturbances, and land use influence dryland vegetation, plant communities, and ecosystem services. He is currently engaged in the broad topics of ecohydrology and dryland sustainability in the western U.S. and has projects examining a) the potential influence of changing climatic conditions on the distribution and regeneration potential of trees and shrubs in the intermountain western U.S., b) strategies for understanding and enhancing dryland ecosystem resilience to changing climate and drought patterns, and c) ecosystem water balance and patterns of plant-available soil water in dryland regions.
Professional Experience
2011- Present: Research Ecologist - US Geological Survey, Southwest Biological Science Center, Flagstaff, AZ
2006 - 2011: Research Ecologist - USDA Forest Service, North Central Research Station, Grand Rapids, MN
2004 - 2006: Research Ecologist (Postdoctoral) - USDA Forest Service, Rocky Mountain Research Station, Fort Collins, CO
Education and Certifications
2004 - Ph.D., Ecology, Colorado State University
1996 - B.A., Biology, Cornell University
Science and Products
Climate disequilibrium dominates uncertainty in long-term projections of primary productivity
Summer 2022 edition
Dry forest decline is driven by both declining recruitment and increasing mortality in response to warm, dry conditions
A sagebrush conservation design to proactively restore America’s sagebrush biome
Southeast Utah Group climate and drought adaptation report: Exposure and perennial grass sensitivity
Primary production responses to extreme changes in North American Monsoon precipitation vary by elevation and plant functional composition through time
Management and environmental factors associated with simulated restoration seeding barriers in sagebrush steppe
Supporting the development and use of native plant materials for restoration on the Colorado Plateau (Fiscal Year 2021 Report)
Landscape-scale forest restoration decreases vulnerability to drought mortality under climate change in southwest USA ponderosa forest
Winter 2020-2021 edition
Soil moisture response to seasonal drought conditions and post-thinning forest structure
New indicators of ecological resilience and invasion resistance to support prioritization and management in the sagebrush biome, United States
Can Management Actions Support Forest Regeneration Across the Diverse Landscapes and Climate Change Futures of the Southwestern U.S.?
Integrating short-term climate forecast into a restoration management support tool
Webinar: Forest Management for Mitigating Drought Impacts
Effects of Climate, Disturbance, and Management on the Growth and Dynamics of Temperate and Sub-Boreal Forest Ecosystems within the Lake States and New England
An Interactive Web-Based Tool for Anticipating Long-term Drought Risk
Improving the Success of Post-Fire Adaptive Management Strategies in Sagebrush Steppe
Big Sagebrush Response to Wildfire and Invasive Grasses in the 21st Century
Mapping the Risk of Ecological Transformation Across Pinyon Woodlands and the U.S. West
Colorado Plateau Futures: Understanding Agents of Change on the Colorado Plateau to Facilitate Collaborative Adaptation
Ecology and Management of Pinyon-Juniper Woodlands: State of the Science
Dryland Forest Sustainability
Ecohydrology and Climate Change in Drylands
A snapshot of stakeholder science needs related to drought in the Colorado River Basin
Simulated rangewide big sagebrush regeneration estimates and relationships with abiotic variables as function of soils under historical and future climate projections
Ecosystem water balance and ecological drought patterns under historical and future climate conditions for the Four Forest Restoration Initiative (4FRI) Landscape
Daily Climate and Soil Moisture Data for the Southern Colorado Plateau Network Parks, 1980 – 2018 (ver. 1.1, November, 2023)
Robust ecological drought projection data for drylands in the 21st century
Stand density and climate data in the Taylor Woods study area (Fort Valley Experimental Forest) on the Colorado Plateau in Northern Arizona, 1961-2011
Pinyon and Juniper location data, including a literature review citation list of Pinyon-Juniper systems from 1909 to 2018
Ecological drought for sagebrush seedings in the Great Basin
Dataset for plant production responses to climate across water-limited regions
Historical and 21st century soil temperature and moisture data for drylands of western U.S. and Canada
Demographic modeling data (including code) at various sites in the Great Basin, USA
Environmental conditions, covariate data used in model fitting, and long-term establishment predictions from 1979 to 2016 in the Great Basin, USA
Science and Products
- Publications
Filter Total Items: 144
Climate disequilibrium dominates uncertainty in long-term projections of primary productivity
Rapid climate change may exceed ecosystems' capacities to respond through processes including phenotypic plasticity, compositional turnover and evolutionary adaption. However, consequences of the resulting climate disequilibria for ecosystem functioning are rarely considered in projections of climate change impacts. Combining statistical models fit to historical climate data and remotely-sensed esAuthorsAndrew J Felton, Robert K Shriver, Michael Stemkovski, John B. Bradford, Katharine N. Suding, Peter B. AdlerSummer 2022 edition
No abstract available.AuthorsMolly L. McCormick, Seth M. Munson, John B. BradfordDry forest decline is driven by both declining recruitment and increasing mortality in response to warm, dry conditions
Aim: Anticipating when and where changes in species' demographic rates will lead to range shifts in response to changing climate remains a major challenge. Despite evidence of increasing mortality in dry forests across the globe in response to drought and warming temperatures, the overall impacts on the distribution of dry forests are largely unknown because we lack comparable large-scale data onAuthorsRobert K. Shriver, Charles Yackulic, David M. Bell, John B. BradfordA sagebrush conservation design to proactively restore America’s sagebrush biome
A working group of experts with diverse professional backgrounds and disciplinary expertise was assembled to conceptualize a spatially explicit conservation design to support and inform the Sagebrush Conservation Strategy Part 2. The goal was to leverage recent advancements in remotely sensed landcover products to develop spatially and temporally explicit maps of sagebrush rangeland condition andAuthorsKevin Doherty, David M. Theobald, John B. Bradford, Lief A. Wiechman, Geoffrey Bedrosian, Chad S. Boyd, Matthew Cahill, Peter S. Coates, Megan K. Creutzburg, Michele R. Crist, Sean P. Finn, Alexander V. Kumar, Caitlin E. Littlefield, Jeremy D. Maestas, Karen L. Prentice, Brian G. Prochazka, Thomas E. Remington, William D. Sparklin, John C. Tull, Zachary Wurtzebach, Katherine A. ZellerSoutheast Utah Group climate and drought adaptation report: Exposure and perennial grass sensitivity
National Park Service (NPS) managers face growing challenges resulting from the effects of climate change. In particular, as temperatures rise in coming decades, natural resource management in the western United States must cope with expectations for elevated severity and frequency of droughts. These challenges are particularly pronounced for vegetation managers in dryland environments. DevelopingAuthorsJohn B. Bradford, Caroline Havrilla, Jessica A. Hartsell, Daniel Rodolphe Schlaepfer, Molly L. McCormick, Seth M. Munson, Charles Yackulic, Terry T Fisk, David Thoma, Dusty Perkins, Dana L. Witwicki, Matt VanScoyoc, Michael C. Duniway, Sasha C. ReedPrimary production responses to extreme changes in North American Monsoon precipitation vary by elevation and plant functional composition through time
Primary production in dryland ecosystems is limited by water availability and projected to be strongly affected by future shifts in seasonal precipitation. Warm-season precipitation derived from the North American Monsoon contributes 40% of annual precipitation to dryland ecosystems in the southwestern U.S. and is projected to become more variable. However, there is large uncertainty on whether thAuthorsSeth M. Munson, John B. Bradford, Bradley J. Butterfield, Jennifer R. GremerManagement and environmental factors associated with simulated restoration seeding barriers in sagebrush steppe
Adverse weather conditions, particularly freezing or drought, are often associated with poor seedling establishment following restoration seeding in drylands like the Great Basin sagebrush steppe (USA). Management decisions such as planting date or seed source could improve restoration outcomes by reducing seedling exposure to weather barriers. We simulated the effects of management and environmenAuthorsStella M. Copeland, John B. Bradford, Stuart P. Hardegree, Daniel Rodolphe Schlaepfer, Kevin J BadikSupporting the development and use of native plant materials for restoration on the Colorado Plateau (Fiscal Year 2021 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 providAuthorsRobert Massatti, Daniel E. Winkler, Sasha C. Reed, Michael C. Duniway, Seth M. Munson, John B. BradfordLandscape-scale forest restoration decreases vulnerability to drought mortality under climate change in southwest USA ponderosa forest
Drought-induced tree mortality is predicted to increase in dry forests across the western USA as future projections show hotter, drier climates potentially resulting in large-scale tree die-offs, changes in species composition, and loss of forest ecosystem services, including carbon storage. While some studies have found that forest stands with greater basal areas (BA) have higher drought mortalitAuthorsLisa A McCauley, John B. Bradford, Marcos D. Robles, Robert K Shriver, Travis J. Woolley, Caitlin M. AndrewsWinter 2020-2021 edition
In this edition: 2021 year in review, native seed development process, RestoreNet protocol published and lots of associated research, a handful of climate change science, and more.AuthorsMolly L. McCormick, Seth M. Munson, John B. BradfordSoil moisture response to seasonal drought conditions and post-thinning forest structure
Prolonged drought conditions in semi-arid forests can lead to widespread vegetation stress and mortality. However, the distribution of these effects is not spatially uniform. We measured soil water potential at high spatial and temporal resolution using 112 sensors distributed across a ponderosa pine forest in northern Arizona, USA, during two abnormally dry years with below-average total precipitAuthorsAdam Belmonte, Temuulen T. Sankey, Joel Biedermann, John B. Bradford, Thomas KolbNew indicators of ecological resilience and invasion resistance to support prioritization and management in the sagebrush biome, United States
Ecosystem transformations to altered or novel ecological states are accelerating across the globe. Indicators of ecological resilience to disturbance and resistance to invasion can aid in assessing risks and prioritizing areas for conservation and restoration. The sagebrush biome encompasses parts of 11 western states and is experiencing rapid transformations due to human population growth, invasiAuthorsJeanne C. Chambers, Jessi L. Brown, John B. Bradford, David I. Board, Steven B. Campbell, Karen J. Clause, Brice Hanberry, Daniel Rodolphe Schlaepfer, Alexandra K. Urza - Science
Filter Total Items: 30
Can Management Actions Support Forest Regeneration Across the Diverse Landscapes and Climate Change Futures of the Southwestern U.S.?
Ponderosa pine forests are declining and their future persistence is uncertain. Most research on forest declines has focused on the effects of disturbances including wildfire, insect outbreaks, and severe drought on mortality of mature trees. Yet, recent research suggests that ponderosa pine declines may be even more severe as these ecosystems fail to regenerate naturally (i.e. grow from seed to aIntegrating short-term climate forecast into a restoration management support tool
Natural resources managers are regularly required to make decisions regarding upcoming restoration treatments, often based on little more than business as usual practices. To assist in the decision-making process, we created a tool that predicts site-specific soil moisture and climate for the upcoming year, and provides guidance on whether common restoration activities (i.e. seeding, planting) wilWebinar: Forest Management for Mitigating Drought Impacts
View this webinar to learn more about forest drought in the Southwest U.S. and ongoing research to mitigate regional drought effects.Effects of Climate, Disturbance, and Management on the Growth and Dynamics of Temperate and Sub-Boreal Forest Ecosystems within the Lake States and New England
Overview This project is using a combination of long-term data records and recently established large-scale adaptive management studies in managed forests across the Lake States, New England, Intermountain West, and Black Hills to identify forest management strategies and forest conditions that confer the greatest levels of resistance and resilience to past and emerging stressors and their reAn Interactive Web-Based Tool for Anticipating Long-term Drought Risk
Droughts are becoming more frequent and severe and this trend is expected to continue in the coming century. Drought effects on natural resources include reduced water availability for plants and humans, as well as increased insect, disease, and vegetation mortality. Land managers need more information regarding how water availability may change and how drought will affect their sites in the futurImproving the Success of Post-Fire Adaptive Management Strategies in Sagebrush Steppe
Sagebrush steppe is one of the most widely distributed ecosystems in North America. Found in eleven western states, this important yet fragile ecosystem is dominated by sagebrush, but also contains a diversity of native shrubs, grasses, and flowering plants. It provides critical habitat for wildlife like pronghorn and threatened species such as the greater sage-grouse, and is grazed by livestock oBig Sagebrush Response to Wildfire and Invasive Grasses in the 21st Century
Big sagebrush plant communities are important and widespread in western North America and are crucial for meeting long-term conservation goals for greater sage-grouse and other wildlife of conservation concern. Yet wildfire is increasing in the West, turning biodiverse, shrub-based ecosystems dominated by sagebrush into grasslands containing invasive species such as cheatgrass and less overall plaMapping the Risk of Ecological Transformation Across Pinyon Woodlands and the U.S. West
Pinyon pine woodlands are among the most widespread and iconic vegetation types in the western United States and support recreation, resource extraction, grazing, and cultural enrichment. However, severe drought conditions have recently caused dramatic mortality of pinyon pines, creating concern about the long-term impact of increasing aridity on the viability of pinyon woodlands. Ecological transColorado Plateau Futures: Understanding Agents of Change on the Colorado Plateau to Facilitate Collaborative Adaptation
The objective of this interdisciplinary research effort is to 1) characterize agents of change important to land management decision makers on the Colorado Plateau; 2) identify and analyze relationships between agents of change and key landscape attributes and processes; 3) collectively assess the influence of agents of change and attributes and processes on the services provided by the ecosystem...Ecology and Management of Pinyon-Juniper Woodlands: State of the Science
Pinyon-juniper woodlands are a major part of western landscapes and are valued for recreational use, cultural resources, watershed protection, and wildlife habitats. These woodlands have been identified by several stakeholders, including natural resource management entities, federal and state agencies, and numerous tribal nations, as important ecosystems that are currently threatened by land treatDryland Forest Sustainability
Forests in the semiarid southwestern U.S. are expected to be highly vulnerable to increasing aridity anticipated with climate change. In particular, low elevation forests and the processes of tree regeneration and mortality are likely to be highly susceptible to climate change. This work seeks to characterize how, where and when forest ecosystems will change and identify management strategies to...Ecohydrology and Climate Change in Drylands
Drylands cover 40% of the global terrestrial surface and provide important ecosystem services. However, climate forecasts in most dryland regions, especially the southwest U.S., call for increasing aridity. Specifically, changing climate will alter soil water availability, which exerts dominant control over ecosystem structure and function in water-limited, dryland ecosystems. This research seeks... - Data
Filter Total Items: 28
A snapshot of stakeholder science needs related to drought in the Colorado River Basin
Stakeholder science needs were determined by reviewing more than 200 recently published literature items and web pages from Colorado River Basin (CRB) stakeholders. These stakeholder communications were used to characterize over 400 stakeholder science needs by reviewing their priorities, strategies, issues, missions, and concerns related to drought in the CRB. Members of the CRB Integrated SciencByArizona Water Science Center, California Water Science Center, Colorado Water Science Center, Fort Collins Science Center, Geology, Geophysics, and Geochemistry Science Center, Nevada Water Science Center, New Mexico Water Science Center, Southwest Biological Science Center, Utah Water Science Center, Wyoming-Montana Water Science Center, Colorado River Basin: Actionable and Strategic Integrated Science and TechnologySimulated rangewide big sagebrush regeneration estimates and relationships with abiotic variables as function of soils under historical and future climate projections
These NetCDF data were compiled to investigate how two complementary models can contribute to our understanding of contemporary and future big sagebrush regeneration across the historical and potential future sagebrush region. Objective of our study was to apply both models to address three specific objectives: (i) examine the geographic patterns of big sagebrush regeneration probabilities that thEcosystem water balance and ecological drought patterns under historical and future climate conditions for the Four Forest Restoration Initiative (4FRI) Landscape
These data were compiled for research pertaining to the effects of stand density treatments on growth rates in semi-arid, ponderosa pine forests. Also, these data examined how the planned restoration treatments in the Four Forests Restoration Initiative (4FRI), the largest forest restoration project being implemented in the United States, would alter landscape-scale patterns of forest growth and dDaily Climate and Soil Moisture Data for the Southern Colorado Plateau Network Parks, 1980 – 2018 (ver. 1.1, November, 2023)
These data are daily climate, water balance, and soil moisture data for 270 plots in the National Park Service (NPS) Southern Colorado Plateau Network (SCPN) Inventory & Monitoring (I&M) network. Climate data was collected from a gridded, daily climate dataset, Daymet (https://daymet.ornl.gov/). Climate, alongside field-collected soils (SoilDepthsByPlot.csv) and vegetation information, were then uRobust ecological drought projection data for drylands in the 21st century
These data represent simulated ecological drought conditions for current climate, and for future climate represented by all available climate models at two time periods during the 21st century. These data were used to: 1) describe geographic patterns in ecological drought under historical climate conditions, 2) quantify the direction and magnitude of change in ecological drought, 3) identify areasStand density and climate data in the Taylor Woods study area (Fort Valley Experimental Forest) on the Colorado Plateau in Northern Arizona, 1961-2011
These data were compiled for research pertaining to the effects of stand density on growth rates in semi-arid forests. Increasing heat and aridity in coming decades is expected to negatively impact tree growth and threaten forest sustainability in dry areas. Maintaining low stand density has the potential to mitigate the negative effects of increasingly severe droughts by minimizing competitive inPinyon and Juniper location data, including a literature review citation list of Pinyon-Juniper systems from 1909 to 2018
These data were compiled for a comprehensive review of pinyon-juniper communities including Pinus edulis, Pinus monophylla, Juniperus osteosperma, Juniperus monosperma, and Juniperus scopulorum. Compiled are a list of references cataloged by the topic of interest resulting from the literature search. The characterization for each reference includes the focal species, descriptions of the site(s) thEcological drought for sagebrush seedings in the Great Basin
Monthly Standardize Precipitation Evapotranspiration Index (SPEI), Daily soil-water potential (MPa) and soil temperature (degree C) data for plots from SageSuccess. The SageSuccess Project is a joint effort between USGS, BLM, and FWS to understand how to establish big sagebrush and ultimately restore functioning sagebrush ecosystems. Improving the success of land management treatments to restore sDataset for plant production responses to climate across water-limited regions
This dataset was constructed from readily available open source climate and vegetation data, like Landsat. This dataset represents the vegetation and climate conditions for a large number of points across the major deserts of the SW USA. The dataset was constructed in order to use the climate pivot point approach (Munson et al. 2013) at the landscape level. Originally this dataset was much largerHistorical and 21st century soil temperature and moisture data for drylands of western U.S. and Canada
These data represent simulated soil temperature and moisture conditions for current climate, and for future climate represented by all available climate models at two time periods during the 21st century. These data were used to: 1) quantify the direction and magnitude of expected changes in several measures of soil temperature and soil moisture, including the key variables used to distinguish theDemographic modeling data (including code) at various sites in the Great Basin, USA
These data were compiled to determine whether transient population dynamics substantially alter population growth rates of sagebrush after disturbance, impede resilience and restoration, and in turn drive ecosystem transformation. Data were collected from 2014-2016 on sagebrush population height distributions at 531 sites across the Great Basin that had burned and were subsequently reseeded by theEnvironmental conditions, covariate data used in model fitting, and long-term establishment predictions from 1979 to 2016 in the Great Basin, USA
Data was collected to characterize the conditions under which sagebrush occurs after seeding and wildfire in the Great Basin, and used to parameterize models used to explore adaptive seeding approaches. Data includes plot level field data on sagebrush occurrence, density, weather, and soil moisture conditions in the year that seeding after wildfire occurred. Weather data includes both average annu - Multimedia
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