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Full-Text Articles in Physical Sciences and Mathematics

Effects Of Changing Climate Extremes And Vegetation Phenology On Wildlife Associated With Grasslands In The Southwestern United States, Tyler G. Creech, Matthew A. Williamson, Steven E. Sesnie, Esther S. Rubin, Daniel R. Cayan, Erica Fleishman Oct 2023

Effects Of Changing Climate Extremes And Vegetation Phenology On Wildlife Associated With Grasslands In The Southwestern United States, Tyler G. Creech, Matthew A. Williamson, Steven E. Sesnie, Esther S. Rubin, Daniel R. Cayan, Erica Fleishman

Human-Environment Systems Research Center Faculty Publications and Presentations

Assessments of the potential responses of animal species to climate change often rely on correlations between long-term average temperature or precipitation and species' occurrence or abundance. Such assessments do not account for the potential predictive capacity of either climate extremes and variability or the indirect effects of climate as mediated by plant phenology. By contrast, we projected responses of wildlife in desert grasslands of the southwestern United States to future climate means, extremes, and variability and changes in the timing and magnitude of primary productivity. We used historical climate data and remotely sensed phenology metrics to develop predictive models of …


Timing And Magnitude Of Drought Impacts On Carbon Uptake Across A Grassland Biome, Andrew Felton, Gregory R. Goldsmith Feb 2023

Timing And Magnitude Of Drought Impacts On Carbon Uptake Across A Grassland Biome, Andrew Felton, Gregory R. Goldsmith

Biology, Chemistry, and Environmental Sciences Faculty Articles and Research

Although drought is known to negatively impact grassland functioning, the timing and magnitude of these impacts within a growing season remains unresolved. Previous small-scale assessments indicate grasslands may only respond to drought during narrow periods within a year; however, large-scale assessments are now needed to uncover the general patterns and determinants of this timing. We combined remote sensing datasets of gross primary productivity and weather to assess the timing and magnitude of grassland responses to drought at 5 km2 temporal resolution across two expansive ecoregions of the western US Great Plains biome: the C4-dominated shortgrass steppe and …


High Winds And Melting Sea Ice Trigger Landward Movement In A Polar Bear Population Of Concern, Annie Kellner, Todd C. Atwood, David C. Douglas, Stewart W. Breck, Colorado State University - Fort Collins Jan 2023

High Winds And Melting Sea Ice Trigger Landward Movement In A Polar Bear Population Of Concern, Annie Kellner, Todd C. Atwood, David C. Douglas, Stewart W. Breck, Colorado State University - Fort Collins

USDA Wildlife Services: Staff Publications

Some animal species are responding to climate change by altering the timing of events like mating and migration. Such behavioral plasticity can be adaptive, but it is not always. Polar bears (Ursus maritimus) from the southern Beaufort Sea subpopulation have mostly remained on ice year-round, but as the climate warms and summer sea ice declines, a growing proportion of the subpopulation is summering ashore. The triggers of this novel behavior are not well understood. Our study uses a parametric time-to-event model to test whether biological and/or time-varying environmental variables thought to influence polar bear movement and habitat selection …


Microscale Pollen Release And Dispersal Patterns In Flowering Grass Populations, Carl A. Frisk, Godfrey P. Apangu, Geoffrey M. Petch, Simon Creer, Mary Hanson, Beverley Adams-Groom, Carsten A. Skjøth Jan 2023

Microscale Pollen Release And Dispersal Patterns In Flowering Grass Populations, Carl A. Frisk, Godfrey P. Apangu, Geoffrey M. Petch, Simon Creer, Mary Hanson, Beverley Adams-Groom, Carsten A. Skjøth

Research outputs 2022 to 2026

Characterizing pollen release and dispersion processes is fundamental for knowledge advancement in ecological, agricultural and public health disciplines. Understanding pollen dispersion from grass communities is especially relevant due to their high species-specific allergenicity and heterogeneously distributed source areas. Here, we aimed to address questions concerning fine level heterogeneity in grass pollen release and dispersion processes, with a focus on characterizing the taxonomic composition of airborne grass pollen over the grass flowering season using eDNA and molecular ecology methods. High resolution grass pollen concentrations were compared between three microscale sites ( < 300 m apart) in a rural area in Worcestershire, UK. The grass pollen was modelled with local meteorology in a MANOVA (Multivariate ANOVA) approach to investigate factors relevant to pollen release and dispersion. Simultaneously, airborne pollen was sequenced using Illumina MySeq for metabarcoding, analysed against a reference database with all UK grasses using the R packages DADA2 and phyloseq to calculate Shannon's Diversity Index ( -diversity). The flowering phenology of a local Festuca rubra population was observed. We found that grass pollen concentrations varied on a microscale level, likely attributed to local topography and the dispersion distance of pollen from flowering grasses in local source areas. Six genera (Agrostis, Alopecurus, Arrhenatherum, Holcus, Lolium and Poa) dominated the pollen season, comprising on average 77 % of the relative abundance of grass species reads. Temperature, solar radiation, relative humidity, turbulence and wind speeds were found to be relevant for grass pollen release and dispersion processes. An isolated flowering Festuca rubra population contributed almost 40 % of the relative pollen abundance adjacent to the nearby sampler, but only contributed 1 % to samplers situated 300 m away. This suggests that most emitted grass pollen has limited dispersion distance and our results show substantial variation in airborne grass species composition over short geographical scales.