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Full-Text Articles in Life Sciences
Forecasting Climate Change Impacts On Plant Populations Over Large Spatial Extents, Andrew T. Tredennick, Melvin Hooten, Cameron L. Aldridge, Collin G. Homer, Andrew R. Kleinhesselink, Peter B. Adler
Forecasting Climate Change Impacts On Plant Populations Over Large Spatial Extents, Andrew T. Tredennick, Melvin Hooten, Cameron L. Aldridge, Collin G. Homer, Andrew R. Kleinhesselink, Peter B. Adler
Wildland Resources Faculty Publications
Plant population models are powerful tools for predicting climate change impacts in one location, but are difficult to apply at landscape scales. We overcome this limitation by taking advantage of two recent advances: remotely sensed, species-specific estimates of plant cover and statistical models developed for spatiotemporal dynamics of animal populations. Using computationally efficient model reparameterizations, we fit a spatiotemporal population model to a 28-year time series of sagebrush (Artemisia spp.) percent cover over a 2.5 × 5 km landscape in southwestern Wyoming while formally accounting for spatial autocorrelation. We include interannual variation in precipitation and temperature as covariates in the …
Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan
Methane Emissions From Global Rice Fields: Magnitude, Spatiotemporal Patterns, And Environmental Controls, Bowen Zhang, Hanqin Tian, Wei Ren, Bo Tao, Chaoqun Lu, Jia Yang, Kamaljit Banger, Shufen Pan
Plant and Soil Sciences Faculty Publications
Given the importance of the potential positive feedback between methane (CH4) emissions and climate change, it is critical to accurately estimate the magnitude and spatiotemporal patterns of CH4 emissions from global rice fields and better understand the underlying determinants governing the emissions. Here we used a coupled biogeochemical model in combination with satellite-derived contemporary inundation area to quantify the magnitude and spatiotemporal variation of CH4 emissions from global rice fields and attribute the environmental controls of CH4 emissions during 1901–2010. Our study estimated that CH4 emissions from global rice fields varied from 18.3 ± …
Long-Term Sandhills Prairie Responses To Precipitation, Temperature, And Cattle Stocking Rate, John A. Guretzky, Cheryl Dunn, Heidi L. Hillhouse
Long-Term Sandhills Prairie Responses To Precipitation, Temperature, And Cattle Stocking Rate, John A. Guretzky, Cheryl Dunn, Heidi L. Hillhouse
Department of Agronomy and Horticulture: Faculty Publications
Understanding of Sandhills prairie, the most expansive sand dune region stabilized by perennial grasses in the Western Hemisphere, is limited by lack of long-term vegetation data. We used a 26-year dataset to evaluate Sandhills prairie responses to yearto- year variation in precipitation, temperature, and cattle stocking rate. Basal cover, a measurement that is constant seasonally and used to detect long-term changes in bunchgrass vegetation, was measured in 38–40 permanent plots positioned along four transects spanning 769 ha from 1979 to 2007. Across this period, total basal cover averaged 2.4 % and was dominated by warm-season grasses (81.1 %). Schizachyrium scoparium …
A Multiple‐Scale Assessment Of Long‐Term Aspen Persistence And Elevational Range Shifts In The Colorado Front Range, Mario Bretfeld, Scott B. Franklin, Robert K. Peet
A Multiple‐Scale Assessment Of Long‐Term Aspen Persistence And Elevational Range Shifts In The Colorado Front Range, Mario Bretfeld, Scott B. Franklin, Robert K. Peet
Aspen Bibliography
Aspen forests and woodlands are some of the most species‐rich forest communities in the northern hemisphere. Changing climate, altered disturbance regimes, land use, and increased herbivore pressure threaten these forests both in Eurasia and North America. In addition, rapid mortality dubbed “Sudden Aspen Decline” is a concern for aspen's long‐term presence in the western United States, especially Colorado and Utah. Yet it is still unclear whether aspen is persistent or declining at the landscape scale. We assessed aspen persistence at different spatial scales in the Colorado Front Range by resampling 89 plots containing aspen from among 305 vegetation plots sampled …
Greater Bud Outgrowth Of Bromus Inermis Than Pascopyrum Smithii Under Multiple Environmental Conditions, Jacqueline P. Ott, Jack L. Butler, Yuping Rong, Lan Xu
Greater Bud Outgrowth Of Bromus Inermis Than Pascopyrum Smithii Under Multiple Environmental Conditions, Jacqueline P. Ott, Jack L. Butler, Yuping Rong, Lan Xu
Natural Resource Management Faculty Publications
Tiller recruitment of perennial grasses in mixed-grass prairie primarily occurs from belowground buds. Environmental conditions, such as temperature, soil moisture and grazing can affect bud outgrowth of both invasive and native perennial grasses. Differential bud outgrowth responses of native and invasive species to climate change and grazing could alter competitive interactions that have implications for future land management. The aims of this work were to (i) compare how spring temperature altered bud outgrowth of native Pascopyrum smithii (Rydb.) Á. Löve (western wheatgrass) and introduced Bromus inermis Leyss.(smooth brome), (ii) compare how watering frequency altered bud outgrowth of these two species …
Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang
Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang
GSCE Faculty Publications
Climate influences geographic differences of vegetation phenology through both contemporary and historical variability. The latter effect is embodied in vegetation heterogeneity underlain by spatially varied genotype and species compositions tied to climatic adaptation. Such long-term climatic effects are difficult to map and therefore often neglected in evaluating spatially explicit phenological responses to climate change. In this study we demonstrate a way to indirectly infer the portion of land surface phenology variation that is potentially contributed by underlying genotypic differences across space. The method undertaken normalized remotely sensed vegetation start-of-season (or greenup onset) with a cloned plants-based phenological model. As the …
Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang
Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang
Geography Faculty Publications
Climate influences geographic differences of vegetation phenology through both contemporary and historical variability. The latter effect is embodied in vegetation heterogeneity underlain by spatially varied genotype and species compositions tied to climatic adaptation. Such long-term climatic effects are difficult to map and therefore often neglected in evaluating spatially explicit phenological responses to climate change. In this study we demonstrate a way to indirectly infer the portion of land surface phenology variation that is potentially contributed by underlying genotypic differences across space. The method undertaken normalized remotely sensed vegetation start-of-season (or greenup onset) with a cloned plants-based phenological model. As the …
Invasion During Extreme Weather: Success And Failure In A Temperate Perennial Grassland, James C. Han, Stephen L. Young
Invasion During Extreme Weather: Success And Failure In A Temperate Perennial Grassland, James C. Han, Stephen L. Young
West Central Research and Extension Center, North Platte
Invasive and native plant species compete for resources in similar pools, with disturbances often favoring the invader. Yet, increased climate variability may be shifting the competitive edge back toward the natives. We conducted field studies in perennial grasslands to determine the effects of clipping and drought on resource availability (light and moisture) and subsequent establishment of Carduus nutans. We measured light penetration and soil moisture content in C. nutans monoculture, clipped and non clipped grassland with C. nutans, and bare ground control plots. We also tracked phenology of the invader and grasses. Our studies revealed that light was a limiting …
Riparian Trees And Aridland Streams Of The Southwestern United States: An Assessment Of The Past, Present, And Future, D. Max Smith, Deborah M. Finch
Riparian Trees And Aridland Streams Of The Southwestern United States: An Assessment Of The Past, Present, And Future, D. Max Smith, Deborah M. Finch
USDA Forest Service / UNL Faculty Publications
Riparian ecosystems are vital components of aridlands within the southwestern United States. Historically, surface flows influenced population dynamics of native riparian trees. Many southwestern streams has been altered by regulation, however, and will be further affected by greenhouse warming. Our analysis of stream gage data revealed that decreases in volume of annual discharge and mean peak discharge and a shift to earlier peak discharge will occur in the Southern Rockies region of Colorado, New Mexico, and Utah. These changes will likely decrease rates of reproduction and survival of cottonwood (Populus fremontii and Populus deltoides ssp. wislizenii), Goodding's willow …
A Forest Vulnerability Index Based On Drought And High Temperatures, David Mildrexler, Zhiqiang Yang, Warren B. Cohen, David M. Bell
A Forest Vulnerability Index Based On Drought And High Temperatures, David Mildrexler, Zhiqiang Yang, Warren B. Cohen, David M. Bell
USDA Forest Service / UNL Faculty Publications
Increasing forest stress and tree mortality has been directly linked to combinations of drought and high temperatures. The climatic changes expected during the next decades – large increases in mean temperature, increased heat waves, and significant long-term regional drying in the western USA – will likely increase chronic forest stress and mortality. The aim of this research is to develop and apply a new forest vulnerability index (FVI) associated with drought and high temperatures across the Pacific Northwest region (PNW; Oregon and Washington) of the USA during the MODIS Aqua era (since 2003). Our technique incorporates the alterations to canopy …
Contributing Factors For Drought In United States Forest Ecosystems Under Projected Future Climates And Their Uncertainty, Charles H. Luce, James M. Vose, Neil Pederson, John Campbell, Connie Millar, Patrick Kormos, Ross Woods
Contributing Factors For Drought In United States Forest Ecosystems Under Projected Future Climates And Their Uncertainty, Charles H. Luce, James M. Vose, Neil Pederson, John Campbell, Connie Millar, Patrick Kormos, Ross Woods
USDA Forest Service / UNL Faculty Publications
Observations of increasing global forest die-off related to drought are leading to more questions about potential increases in drought occurrence, severity, and ecological consequence in the future. Dry soils and warm temperatures interact to affect trees during drought; so understanding shifting risks requires some understanding of changes in both temperature and precipitation. Unfortunately, strong precipitation uncertainties in climate models yield substantial uncertainty in projections of drought occurrence. We argue that disambiguation of drought effects into temperature and precipitation-mediated processes can alleviate some of the implied uncertainty. In particular, the disambiguation can clarify geographic diversity in forest sensitivity to multifarious drivers …
Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez
Simulating Long-Term Impacts Of Cover Crops And Climate Change On Crop Production And Environmental Outcomes In The Midwestern United States, Andrea D. Basche, Sotririos V. Archontoulis, Thomas C. Kaspar, Dan B. Jaynes, Timothy B. Parkin, Fernando E. Miguez
Department of Agronomy and Horticulture: Faculty Publications
It is critical to evaluate conservation practices that protect soil and water resources from climate change in the Midwestern United States, a region that produces one-quarter of the world’s soybeans and one-third of the world’s maize. An over-winter cover crop in a maize–soybean rotation offers multiple potential benefits that can reduce the impacts of higher temperatures and more variable rainfall; some of the anticipated changes for the Midwest. In this experiment we used the Agricultural Production Systems sIMulator (APSIM) to understand how winter rye cover crops impact crop production and environmental outcomes, given future climate change. We first tested APSIM …