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Droughts are disproportionately impacting global dryland regions where ecosystem health and function are tightly coupled to moisture availability. Drought severity is commonly estimated using algorithms such as the standardized precipitation-evapotranspiration index (SPEI), which can estimate climatic water balance impacts at various hydrologic scales by varying computational length. However, the performance of these metrics as indicators of soil moisture dynamics at ecologically relevant scales, across soil depths, and in consideration of broader scale ecohydrological processes, requires more attention. In this study, we tested components of climatic water balance, including SPEI and SPEI computation lengths, to...
Categories: Publication; Types: Citation
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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...
Pinyon–juniper (PJ) woodlands are an important component of dryland ecosystems across the US West and are potentially susceptible to ecological transformation. However, predicting woodland futures is complicated by species-specific strategies for persisting and reproducing under drought conditions, uncertainty in future climate, and limitations to inferring demographic rates from forest inventory data. Here, we leverage new demographic models to quantify how climate change is expected to alter population demographics in five PJ tree species in the US West and place our results in the context of a climate adaptation framework to resist, accept, or direct ecological transformation. Two of five study species, Pinus...
Categories: Publication; Types: Citation
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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,...
Categories: Data; Tags: Arizona, Botany, California, Colorado, Ecology, All tags...
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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.
Categories: Data; Tags: Arizona, Botany, California, Climatology, Colorado, All tags...
Climate change is expected to alter the distribution and abundance of tree species, impacting ecosystem structure and function. Yet, anticipating where this will occur is often hampered by a lack of understanding of how demographic rates, most notably recruitment, vary in response to climate and competition across a species range. Using large-scale monitoring data on two dry woodland tree species (Pinus edulis and Juniperus osteosperma), we develop an approach to infer recruitment, survival, and growth of both species across their range. In doing so, we account for ecological and statistical dependencies inherent in large-scale monitoring data. We find that drying and warming conditions generally lead to declines...
Categories: Publication; Types: Citation
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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.
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Environmental Analysis Data: These data were compiled to investigate the complex interactions between environmental gradients and geographic distance across the Intermountain West of the western United States. Due to complex topography, physiographic heterogeneity, and complicated relationships with large bodies of water, spatial autocorrelation of environmental similarity may be expected. We provide an R script (VarioAnalysis.R) that uses four associated data files (annualprecip.csv, annualSWA.csv, annualtemp.csv, key.csv) to reproduce Figure 3 in Massatti et al. 2020 (see Larger Work Citation). The data files contain information on yearly soil water availability, temperature, and precipitation, which are summed...
Tags: Arizona, Botany, California, Climatology, Colorado, All tags...


    map background search result map search result map Environmental conditions, covariate data used in model fitting, and long-term establishment predictions from 1979 to 2016 in the Great Basin, USA Demographic modeling data (including code) at various sites in the Great Basin, USA Population genetic and climatic variability data across western North America, 1915-2015 Estimated tree mortality, basal area, climate, and drought conditions for ponderosa pine in forest inventory plots across the western U.S. Pinyon-juniper basal area, climate and demographics data from National Forest Inventory plots and projected under future density and climate conditions 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 Pinyon-juniper basal area, climate and demographics data from National Forest Inventory plots and projected under future density and climate conditions Estimated tree mortality, basal area, climate, and drought conditions for ponderosa pine in forest inventory plots across the western U.S. Population genetic and climatic variability data across western North America, 1915-2015