Filters: Tags: Information Sciences (X) > partyWithName: U.S. Geological Survey - ScienceBase (X) > partyWithName: John B Bradford (X)
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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 the regimes used in the R and R categories; 2) assess how these changes will impact the geographic distribution of soil temperature and moisture regimes; and 3) explore the implications for using R and R categories for estimating future ecosystem resilience and resistance.
These data were compiled as a supplement to a previously published journal article (Bradford et al., 2019), that employed a ecosystem water balance model to characterize current and future patterns in soil temperature and moisture conditions in dryland areas of western North America. Also, these data are associated with a published USGS data release (Bradford and Schlaepfer, 2019). The objectives of our study were to (1) characterize current and future patterns in soil temperature and moisture conditions in dryland areas of western North America, (2) evaluate the impact of these changes on estimation of resilience and resistance among a representative set of climate scenarios. These data represent geographic patterns...
These data were compiled to evaluate the magnitude and direction of change from historical conditions in climate metrics across the Southeastern Utah Group (SEUG) of National Parks. Objective(s) of our study were to quantify the magnitude and direction of change from historical conditions in climate metrics across SEUG parks at a meaningful scale for land managers and practitioners. These data represent the historical and projected future average temperatures for two emission scenarios and 12 global circulation models. Included are the annual average temperatures and the average temperatures for each season. These data were created by sampling representative locations across each National Park unit and simulating...
Biome-wide sagebrush core habitat and growth areas estimated from a threat-based conservation design
These data were compiled as a part of a landscape conservation design effort for the sagebrush biome, and are the result of applying a spatially explicit model that assessed geographic patterns in sagebrush ecological integrity and used these results to identify Core Sagebrush Areas (CSAs), Growth Opportunity Areas (GOAs), and Other Rangeland Areas (ORAs). Our overall objective in this study was to characterize geographic patterns in ecological integrity of sagebrush ecosystems. These data represent the estimated integrity of sagebrush ecosystems, estimated from a spatial model that assigns high integrity is areas with abundant big sagebrush and perennial grass/forb cover and with minimal annual grass/forb cover,...
These data consist of environmental covariates, measured plot-level and tree characteristics for seven coniferous tree species across the southwestern United States. The objectives of the study were to assess how growth characteristics of conifer tree species vary across environmental gradients and across the different tree species. These data represent conifer growth under a variety of stand and site characteristics. These data were collected in the summer of 2019, from sites across Nevada, Arizona, New Mexico and Colorado, and collected by field crews directed by Matt Petrie (University of Nevada Las Vegas), Rob Hubbard (USDA Forest Service), Tom Kolb (Northern Arizona University) and John Bradford (U.S. Geological...
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 areas and ecological drought metrics with projected changes that are robust across climate models, defined as drought metrics and locations where >90% of climate models agree in the direction of change.
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 the BLM. These data include field data on sagebrush density in 6 size classes and site attributes (seeding year, sampling year, random site designation, elevation, seeding rate). Also included are modeled spring soil moisture data at each site from the year of seeding to sampling. This data release includes associated software...
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) the study was conducted at, type of study, any land management treatments and the measured response variables. The location data for publications that provided location information have also been compiled in order to compare the geographic distribution of these studies with the distribution of the focal tree species.
These data were compiled to help understand how climate change may impact dryland pinyon-juniper ecosystems in coming decades, and how resource management might be able to minimize those impacts. Objective(s) of our study were to model the demographic rates of PJ woodlands to estimate the areas that may decline in the future vs. those that will be stable. We quantified populations growth rates across broad geographic areas, and identified the relative roles of recruitment and mortality in driving potential future changes in population viability in 5 tree species that are major components of these dry forests. We used this demographic model to project pinyon-juniper population stability under future climate conditions,...
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 the two different models project under historical conditions and future climate scenarios; (ii) quantify the robustness of model projections, e.g., the consistency among climate models in projected changes in regeneration for future time periods; and (iii) identify how model predictions for regeneration potential relate to...
High-resolution maps of big sagebrush plant community biomass using multivariate matching algorithms
These GeoTIFF data were compiled to investigate how a new multivariate matching algorithm transfers simulated plant functional biomass of big sagebrush plant communities from 200 sites to a gridded product with 30-arcsec spatial resolution. Objectives of our study were to (1) describe how climate change will alter the biomass and composition of key plant functional types; (2) quantify the impacts of climate change on future functional type biomass and composition along climatic gradients; (3) identify if and which geographic locations will be relatively unaffected by climate change while others experience large effects; and (4) determine if there is consistency in climate change impacts on plant communities among...
These data consist of environmental covariates and estimated plot-level mortality of ponderosa pine trees. Environmental covariates include growing season temperature and soil moisture, and values are summarized into long-term mean conditions, and anomalies observed between forest inventory sampling events for each plot. Data also include plot locations (with uncertainty introduced by the US Forest Service to maintain private property rights), plot basal area, and several variables related to estimated mortality rate of ponderosa pine trees under various assumptions about basal area conditions.
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 annual summaries and average weather at 5-day intervals from day 1-250 of the year of seeding. Also included are summaries of annual temperature and soil moisture conditions from 1979 to 2016 and model predictions of the probability of sagebrush establishment in each of these years.
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 larger but we were looking to study a pure vegetation signal and therefore developed a detailed masking procedure to remove fire, slope, human, and floodplain effects. The vegetation classification originally came from SW regap, though we have refined / regrouped the data. The vegetation classification for each point is representative...
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 drought vulnerability throughout the 21st century. Using drought-growth relationships developed within the landscape, we considered a suite of climate and thinning scenarios and estimated both average forest growth and the proportion of years with extremely low growth as a measure of vulnerability to long-term decline. The...
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 drought vulnerability throughout the 21st century. Using drought-growth relationships developed within the landscape, we considered a suite of climate and thinning scenarios and estimated both average forest growth and the proportion of years with extremely low growth as a measure of vulnerability to long-term decline. The...
These data were compiled to represent the distribution of environmental conditions with recognized importance to perennial grasses in dryland areas of the western U.S. Objective(s) of our study were to … evaluate how those environmental drivers are related to perennial grass distributions and use the results to assess how perennial grass distributions may shift in response to future climate change. These data represent ecological niche models for 11 perennial grass species that are important components of grasslands on the Colorado Plateau. Data are provided as rasters (tif format) with each containing data about future change in climatic suitability for a give species, future time period, representative concentration...
Categories: Data Release - Provisional,
Data Release - Revised;
Tags: 30-arcsecond,
Arizona,
Botany,
C3,
C4,
These data were compiled so that annual wildfire could be modelled across the sagebrush region in the western United States. Our goal was to understand how wildfire probability relates to climate and fuel conditions across the entire sagebrush region. To do this we developed a statistical model that represents the relationship between annual wildfire probability and a small number of climate and fuel variables. Specifically, created predictions of wildfire probability using a biologically plausible logistic regression model that related wildfire probability to mean temperature, annual precipitation, the proportion summer precipitation (PSP), and aboveground biomass of annual herbaceous plants and perennial herbaceous...
Categories: Data;
Types: Downloadable,
GeoTIFF,
Map Service,
Raster;
Tags: Arizona,
Botany,
California,
Climatology,
Colorado,
These data are species distribution information assembled for assessing the impacts of land-use barriers, facilitative interactions with other species, and loss of long-distance animal dispersal on predicted species range patterns for four common species in pinyon-juniper woodlands in the western United States. The layers in the data release are initial distribution records of two kinds: point occurrence records and a raster layer for the general vegetation types where the species is a co-dominant, compiled from other sources. Both types of data are the baseline information in species distribution models for the associated publication.
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 intensity. By inspecting growth rates and the climate and soil moisture conditions that drive these growth rates we can understand better the positive effects of reducing stand density and the specific dynamics that are beneficial to growth.
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