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Full-Text Articles in Life Sciences

Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson Dec 2016

Impacts Of Long-Term Precipitation Manipulation On Hydraulic Architecture, Xylem Function, And Canopy Status In A Piñon-Juniper Woodland, Patrick J. Hudson

Biology ETDs

The Southwestern US is predicted to become hotter and drier, as global climate change forces increasing temperatures and variability in timing and size of precipitation inputs. Drought stress has become more frequent in recent decades, and resulted in massive forest mortality in piñon-juniper woodlands. During recent severe droughts (2000-2003, 2009-2012), piñon pine (Pinus edulis Englem.) suffered disproportionately high mortality compared to co-occurring one-seed juniper (Juniperus monosperma [Engelm.] Sarg.). A large-scale precipitation manipulation experiment was established in a piñon-juniper woodland in central New Mexico to test hypotheses regarding tree survival and mortality with respect to altered water regimes. Our treatments consisted ...


Interannual Water-Level Fluctuations And The Vegetation Of Prairie Potholes: Potential Impacts Of Climate Change, Arnold G. Van Der Valk, David M. Mushet Dec 2016

Interannual Water-Level Fluctuations And The Vegetation Of Prairie Potholes: Potential Impacts Of Climate Change, Arnold G. Van Der Valk, David M. Mushet

Ecology, Evolution and Organismal Biology Publications

Mean water depth and range of interannual water-level fluctuations over wet-dry cycles in precipitation are major drivers of vegetation zone formation in North American prairie potholes. We used harmonic hydrological models, which require only mean interannual water depth and amplitude of water-level fluctuations over a wet–dry cycle, to examine how the vegetation zones in a pothole would respond to small changes in water depth and/or amplitude of water-level fluctuations. Field data from wetlands in Saskatchewan, North Dakota, and South Dakota were used to parameterize harmonic models for four pothole classes. Six scenarios in which small negative or positive ...


A Possible Constraint On Regional Precipitation Intensity Changes Under Global Warming, W. J. Gutowski Jr., E. S. Takle, K. A. Kozak, J. C. Patton, R. W. Arritt, J. H. Christensen Nov 2016

A Possible Constraint On Regional Precipitation Intensity Changes Under Global Warming, W. J. Gutowski Jr., E. S. Takle, K. A. Kozak, J. C. Patton, R. W. Arritt, J. H. Christensen

William J. Gutowski, Jr.

Changes in daily precipitation versus intensity under a global warming scenario in two regional climate simulations of the United States show a well-recognized feature of more intense precipitation. More important, by resolving the precipitation intensity spectrum, the changes show a relatively simple pattern for nearly all regions and seasons examined whereby nearly all high-intensity daily precipitation contributes a larger fraction of the total precipitation, and nearly all low-intensity precipitation contributes a reduced fraction. The percentile separating relative decrease from relative increase occurs around the 70th percentile of cumulative precipitation, irrespective of the governing precipitation processes or which model produced the ...


Forecasting Climate Change Impacts On Plant Populations Over Large Spatial Extents, Andrew T. Tredennick, Mevi B. Hooten, Cameron L. Aldridge, Collin G. Homer, Andrew R. Kleinhesselink, Peter Adler Oct 2016

Forecasting Climate Change Impacts On Plant Populations Over Large Spatial Extents, Andrew T. Tredennick, Mevi B. Hooten, Cameron L. Aldridge, Collin G. Homer, Andrew R. Kleinhesselink, Peter 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 ...


Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang Sep 2016

Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang

Xiaoyang Zhang

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 ...


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 Sep 2016

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 ...


Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu Aug 2016

Agro-Climatic Change, Crop Production And Mitigation Strategies-Case Studies In Arkansas, Usa And Kenya, John Westley Magugu

Theses and Dissertations

Although climate change impacts vary geographically and temporally, studies at local levels are not readily available for stakeholders to better understand how their local communities would be affected and what remedial measures could be more effective in their local contexts. This dissertation has examined climate change and its impacts in two different local contexts: eastern Arkansas in the USA and Nyando in Kenya. The first part of this dissertation develops agro-meteorological indicators and examines the relationship between agro-meteorological indicators and crop yields in eastern Arkansas between 1960 and 2014. Results reveal that temperature based indicators were more strongly correlated to ...


Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole Jul 2016

Combinatory Effect Of Changing Co2, Temperature, And Long-Term Growth Temperature On Isoprene Emissions, Michael Cole

DePaul Discoveries

Isoprene, the most abundant hydrocarbon in the atmosphere, plays a significant role in atmospheric chemistry. Its reactions with NOx lead to the formation of ozone in the lower troposphere, which is harmful to plants and detrimental to human health. As air temperatures and CO2 concentrations increase with climate change, it is uncertain how isoprene emissions from plants will respond. We hypothesized that isoprene emissions will increase with the combination of increasing temperature and CO­2 concentrations. We predict that oaks grown at a higher temperature will exhibit an increase in isoprene emissions with combined short-term increases in temperature ...


Long-Term Sandhills Prairie Responses To Precipitation, Temperature, And Cattle Stocking Rate, John A. Guretzky, Cheryl Dunn, Heidi L. Hillhouse Jun 2016

Long-Term Sandhills Prairie Responses To Precipitation, Temperature, And Cattle Stocking Rate, John A. Guretzky, Cheryl Dunn, Heidi L. Hillhouse

Agronomy & 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 ...


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 May 2016

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 ...


Greater Bud Outgrowth Of Bromus Inermis Than Pascopyrum Smithii Under Multiple Environmental Conditions, Jacqueline P. Ott, Jack L. Butler, Yuping Rong, Lan Xu May 2016

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 ...


Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen Apr 2016

Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen

Frank S. Gilliam

Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over ...


Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen Apr 2016

Microclimate Moderates Plant Responses To Macroclimate Warming, Pieter De Frenne, Francisco Rodríguez-Sánchez, David Anthony Coomes, Lander Baeten, Gorik Verstraeten, Mark Vellend, Markus Bernhardt-Römermann, Carissa D. Brownd, Jörg Brunet, Johnny Cornelis, Guillaume M. Decocq, Hartmut Dierschke, Ove Eriksson, Frank S. Gilliam, Radim Hédl, Thilo Heinken, Martin Hermy, Patrick Hommel, Michael A. Jenkins, Daniel L. Kelly, Keith J. Kirby, Fraser J. G. Mitchell, Tobias Naaf, Miles Newman, George Peterken, Petr Petrík, Jan Schultz, Grégory Sonnier, Hans Van Calster, Donald M. Waller, Gian-Reto Walther, Peter S. White, Kerry D. Woods, Monika Wulf, Bente Jessen Graae, Kris Verheyen

Frank S. Gilliam

Recent global warming is acting across marine, freshwater, and terrestrial ecosystems to favor species adapted to warmer conditions and/or reduce the abundance of cold-adapted organisms (i.e., “thermophilization” of communities). Lack of community responses to increased temperature, however, has also been reported for several taxa and regions, suggesting that “climatic lags” may be frequent. Here we show that microclimatic effects brought about by forest canopy closure can buffer biotic responses to macroclimate warming, thus explaining an apparent climatic lag. Using data from 1,409 vegetation plots in European and North American temperate forests, each surveyed at least twice over ...


Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang Apr 2016

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 ...


Mapping Temperate Vegetation Climate Adaptation Variability Using Normalized Land Surface Phenology, Liang Liang, Mark D. Schwartz, Xiaoyang Zhang Apr 2016

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 ...


A Forest Vulnerability Index Based On Drought And High Temperatures, David Mildrexler, Zhiqiang Yang, Warren B. Cohen, David M. Bell Jan 2016

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 water and ...


Nitrous Oxide Emissions And Carbon Sequestration In Turfgrass: Effects Of Irrigation And Nitrogen Fertilization (Year 1), R. Braun, D. Bremer, J. Fry Jan 2016

Nitrous Oxide Emissions And Carbon Sequestration In Turfgrass: Effects Of Irrigation And Nitrogen Fertilization (Year 1), R. Braun, D. Bremer, J. Fry

Kansas Agricultural Experiment Station Research Reports

In this study, annual nitrous oxide (N2O) emissions were greatest in urea and least in untreated (no N) among treatments. Differences were negligible due to irrigation treatment. Irrigation levels may be decreased further in the final year to induce slight stress on the low irrigation treatment. All fertilizer treatments maintained acceptable quality, however the controlled-release fertilizer resulted in more consistent visual quality ratings compared to urea and untreated. Urea fertilizer had higher peak fluxes after fertilization and overall annual emissions than polymer-coated N-fertilizer. Thus, controlled released N fertilizers, such as polymer-coated urea, in turfgrass systems could potentially help ...


Enhancement Of The Role Of Spatial Planning In Climate Change Adaptation By Long Term Modelling Of Land Use Change In Hungary, Krisztián Schneller, Erzsébet Vajdovich Visy, Vilja Vaszócsik Jan 2016

Enhancement Of The Role Of Spatial Planning In Climate Change Adaptation By Long Term Modelling Of Land Use Change In Hungary, Krisztián Schneller, Erzsébet Vajdovich Visy, Vilja Vaszócsik

Proceedings of the Fábos Conference on Landscape and Greenway Planning

The purposeful formation of land use significantly contributes to the moderation of the adverse impact of climate change. Since spatial planning plays a fundamental role in the formation of land use, therefore it is essential to integrate climate adaptation goals into the planning process (Biesbroek, G.R. et al., 2009). Spatial plans primarily assist the achievement of adaptation purposes by the delimitation and protection (primarily against urban sprawl) of areas (as zones, such as ecological corridors) which are important in adaptation and risk prevention. In Hungary at present the spatial planning system already contribute to the above mentioned objectives, but ...


Sustainable Urban Planning And Climate Change Scenarios: An Investigation Of Staten Island's Urban Planning, Melissa Wagner, Lauren E. Gentile, Joanna Merson, Elizabeth Wentz Jan 2016

Sustainable Urban Planning And Climate Change Scenarios: An Investigation Of Staten Island's Urban Planning, Melissa Wagner, Lauren E. Gentile, Joanna Merson, Elizabeth Wentz

Proceedings of the Fábos Conference on Landscape and Greenway Planning

Recent events like Hurricane Sandy, which struck Staten Island, NY on October 29, 2012, serve as a costly reminder of how unsustainable designs and mounting social pressures can contribute to extensive structural damage and subsequent financial cost, from storm surge inundation and coastal flooding. It is unlikely that Hurricane Sandy was a one-time event but rather a warning of what can occur over the next century without proper mitigation strategies. Based on climate change projections, such extreme events are expected to become more frequent and intense due to warmer sea surface temperatures and rising sea levels (Emmanual, 2005; Kirtman et ...


The Costs Of Photorespiration To Food Production Now And In The Future, Berkley J. Walker, Andy Vanloocke, Carl J. Bernacchi, Donald R. Ort Jan 2016

The Costs Of Photorespiration To Food Production Now And In The Future, Berkley J. Walker, Andy Vanloocke, Carl J. Bernacchi, Donald R. Ort

Agronomy Publications

Photorespiration is essential for C3 plants but operates at the massive expense of fixed carbon dioxide and energy. Photorespiration is initiated when the initial enzyme of photosynthesis, ribulose-1,5-bisphosphate carboxylase/ oxygenase (Rubisco), reacts with oxygen instead of carbon dioxide and produces a toxic compound that is then recycled by photorespiration. Photorespiration can be modeled at the canopy and regional scales to determine its cost under current and future atmospheres. A regional-scale model reveals that photorespiration currently decreases US soybean and wheat yields by 36% and 20%, respectively, and a 5% decrease in the losses due to photorespiration would be worth ...


Riparian Trees And Aridland Streams Of The Southwestern United States: An Assessment Of The Past, Present, And Future, D. Max Smith, Deborah M. Finch Jan 2016

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 (Salix ...


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 Jan 2016

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 ...


Invasion During Extreme Weather: Success And Failure In A Temperate Perennial Grassland, James C. Han, Stephen L. Young Jan 2016

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 ...


Recent Afforestation In The Iowa River And Vorskla River Basins: A Comparative Trends Analysis, Yury G. Chendev, Jason A. Hubbart, Edgar A. Terekhin, Anthony R. Lupo, Tom J. Sauer, C. Lee Burras Jan 2016

Recent Afforestation In The Iowa River And Vorskla River Basins: A Comparative Trends Analysis, Yury G. Chendev, Jason A. Hubbart, Edgar A. Terekhin, Anthony R. Lupo, Tom J. Sauer, C. Lee Burras

Agronomy Publications

Afforestation trends were compared between two continentally-distinct, yet similar ecoregions to characterize similarities or differences in forest advancement due to natural and anthropogenic forcings. Temporal changes in forest cover were analyzed using high resolution aerial and satellite photographs for Southeast Iowa, USA, and satellite photographs for the western Belgorod Oblast, Russia. An increase in forested area was shown to occur over a 44-year period from 1970–2014 in Iowa where afforestation was reflected by the aggregation of smaller forest units. In the Belgorod region the opposite occurred in that there was an increase in the number of smaller forested units ...


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 Jan 2016

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

Agronomy & 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 ...


Identifying Plant Functional Traits To Assist Ecological Intervention In A Drying Landscape, Ana Luiza Muler Jan 2016

Identifying Plant Functional Traits To Assist Ecological Intervention In A Drying Landscape, Ana Luiza Muler

Theses: Doctorates and Masters

Mediterranean-type ecosystems (MTEs) are among the most vulnerable to land use and climate change and many attempts are in place to restore these ecosystems. Therefore, it is necessary to assess differences in plants’ ability to withstand water-stress, including biotic interactions. Such knowledge helps us understand community assembly, which is crucial for ecological intervention. This study involved: (1) reviewing the literature on traits that can differentiate functional types; (2) adapting the methodology to measure leaf water potential at turgor loss point (πtlp) for small-leaved species; (3) using these traits to quickly identify water-use strategies of adult plants from Southwest Australia ...