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Full-Text Articles in Life Sciences

Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca Dec 2013

Assessing Growth Response To Climate Controls In A Great Basin Artemisia Tridentata Plant Community, Lorenzo F. Apodaca

UNLV Theses, Dissertations, Professional Papers, and Capstones

An assessment of the growth response of key vegetative species to climatic variability is vital to identifying possible local impacts on ecosystems faced with imminent climate change. With current climate projections in Nevada predicting a shift to an even more arid climate with greater year-to-year variability, the imperative exists to identify the effects of specific climatic controls on plant growth and to research methods to assess large-scale vegetative changes, especially in more remote areas where readily available data sets may be lacking. This study utilized annual growth ring indices constructed from big sagebrush (Artemisia tridentatassp.tridentata) stems collected in Spring ...


Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen Sep 2013

Evidence For 20th Century Climate Warming And Wetland Drying In The North American Prairie Pothole Region, Brett A. Werner, W. Carter Johnson, Glenn R. Guntenspergen

Natural Resource Management Faculty Publications

The Prairie Pothole Region (PPR) of North America is a globally important resource that provides abundant and valuable ecosystem goods and services in the form of biodiversity, groundwater recharge, water purification, flood attenuation, and water and forage for agriculture. Numerous studies have found these wetlands, which number in the millions, to be highly sensitive to climate variability. Here, we compare wetland conditions between two 30-year periods (1946–1975; 1976–2005) using a hindcast simulation approach to determine if recent climate warming in the region has already resulted in changes in wetland condition. Simulations using the WETLANDSCAPE model show that 20th ...


Collaborative Research: Globec Pan-Regional Synthesis: End-To-End Energy Budgets In Us-Globec Regions, Andrew C. Thomas Aug 2013

Collaborative Research: Globec Pan-Regional Synthesis: End-To-End Energy Budgets In Us-Globec Regions, Andrew C. Thomas

University of Maine Office of Research Administration: Grant Reports

The research addresses the overarching question: are marine food webs leading to fisheries controlled from the top-down, the bottom up, or a combination of the two? To address this question we will (1) compare end-to-end energy budgets of the 4 US-GLOBEC study regions in the context of top-down v. bottom-up forcing, (2) assess the skills of the regional models in capturing basic material fluxes, (3) extract diagnostics from the regional models that will be used to evaluate the effects of climate change and fishing pressure across GLOBEC regions and (4) develop quantitative methods to compare the diagnostics. The major successes ...


Fisheries Management In A Changing Climate: Lessons From The 2012 Ocean Heat Wave In The Northwest Atlantic., Katherine E. Mills, Andrew Pershing, Curtis J. Brown, Yong Chen, Fu-Sung Chiang, Daniel S. Holland, Sigrid Lehuta, Janet A. Nye, Jenny C. Sun, Andrew C. Thomas, Richard A. Wahle Jun 2013

Fisheries Management In A Changing Climate: Lessons From The 2012 Ocean Heat Wave In The Northwest Atlantic., Katherine E. Mills, Andrew Pershing, Curtis J. Brown, Yong Chen, Fu-Sung Chiang, Daniel S. Holland, Sigrid Lehuta, Janet A. Nye, Jenny C. Sun, Andrew C. Thomas, Richard A. Wahle

Publications

No abstract provided.


Marine Invertebrates: Communities At Risk, Jennifer A. Mather Jun 2013

Marine Invertebrates: Communities At Risk, Jennifer A. Mather

Ecological Impacts of Climate Change Collection

Our definition of the word ‘animal’ centers on vertebrates, yet 99% of the animals on the planet are invertebrates, about which we know little. In addition, although the Census of Marine Life (COML.org) has recently conducted an extensive audit of marine ecosystems, we still do not understand much about the animals of the seas. Surveys of the best-known ecosystems, in which invertebrate populations often play a key role, show that the invertebrate populations are affected by human impact. Coral animals are the foundation of coral reef systems, which are estimated to contain 30% of the species in the ocean ...


Colorado River Cutthroat Habitat Resistance And Resilience To Climate Change, Kate Olsen May 2013

Colorado River Cutthroat Habitat Resistance And Resilience To Climate Change, Kate Olsen

All Graduate Theses and Dissertations

Colorado River cutthroat trout, Oncorhyncus clarki pleuriticus , occupy less than 12% of their historic range. Restoration and conservation of this species are currently under way across the upper Colorado River basin, but guidance to inform management decisions related to the impacts of climate change on cutthroat is lacking. Shifts in the thermal distribution of freshwater fish have been documented, and will continue to occur as cold water habitat is threatened by warming water temperatures. Coupled air and water temperature data allow for an estimation of potential resistance and resilience to warming, determining the effect that local air has on stream ...


Fine Scale Climatic And Soil Variability Effects On Plant Species Cover Along The Front Range Of Colorado, Usa, William Frank Preston Cumming Jan 2013

Fine Scale Climatic And Soil Variability Effects On Plant Species Cover Along The Front Range Of Colorado, Usa, William Frank Preston Cumming

Geography Graduate Theses & Dissertations

Fine scale studies are rarely performed to address landscape level responses to microclimatic variability. Is it the timing, distribution, and magnitude of soil temperature and moisture that affects what species emerge each season and, in turn, their resilience to fluctuations in microclimate. For this dissertation research, I evaluated the response of vegetation change to microclimatic variability within two communities over a three year period (2009-2012) utilizing 25 meter transects at two locations along the Front Range of Colorado near Boulder, CO and Golden, CO respectively. To assess microclimatic variability, spatial and temporal autocorrelation analyses were performed with soil temperature and ...


Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller Jan 2013

Changes In Net Ecosystem Production Over The Past 40 Years In Arctic Tundra Ponds Near Barrow, Alaska: Application Of Historic And Modern Techniques, Nickole Ann Miller

Open Access Theses & Dissertations

Arctic environments have gained interest recently due to their sensitivity to climate change. As warming has created longer growing seasons, extended ice-free periods as well as permafrost thaw, the production in freshwater ecosystems has the potential to be greatly impacted. It is hypothesized that as climate change and warming occurs, increases in primary production will occur and ponds will become carbon sinks. Net ecosystem production (NEP) was determined using phytoplankton and periphyton samples collected weekly during the growing season (June - August) from arctic tundra ponds near Barrow, Alaska. Enrichment with 14C was used to determine both weekly photosynthetic rates and ...


Moving Forward In Global-Change Ecology: Capitalizing On Natural Variability, Inés Ibáñez, Elise S. Gornish, Lauren Buckley, Diane M. Debinski, Jessica Hellmann, Brian Helmuth, Janneke Hillerislambers, Andrew M. Latimer, Abraham J. Miller-Rushing, Maria Uriarte Jan 2013

Moving Forward In Global-Change Ecology: Capitalizing On Natural Variability, Inés Ibáñez, Elise S. Gornish, Lauren Buckley, Diane M. Debinski, Jessica Hellmann, Brian Helmuth, Janneke Hillerislambers, Andrew M. Latimer, Abraham J. Miller-Rushing, Maria Uriarte

Ecology, Evolution and Organismal Biology Publications

Natural resources managers are being asked to follow practices that accommodate for the impact of climate change on the ecosystems they manage, while global-ecosystems modelers aim to forecast future responses under different climate scenarios. However, the lack of scientific knowledge about short-term ecosystem responses to climate change has made it difficult to define set conservation practices or to realistically inform ecosystem models. Until recently, the main goal for ecologists was to study the composition and structure of communities and their implications for ecosystem function, but due to the probable magnitude and irreversibility of climate-change effects (species extinctions and loss of ...


A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur Jan 2013

A History Of Place: Using Phytolith Analysis To Discern Holocene Vegetation Change On Sanak Island, Western Gulf Of Alaska, Cricket C. Wilbur

Dissertations & Theses

This study investigated a terrestrial climate proxy, phytoliths, as a complimentary approach to documenting the dynamics of present and past vegetation on Sanak Island, the largest island in a small island group in the eastern Aleutian archipelago, and as a new basis by which to interpret Holocene environmental variability in Alaska. A phytolith reference collection was established from 59 selected plant species of maritime tundra belonging to 27 families. The grass species and a sedge species produced abundant phytolith forms whereas the majority of dicotyledons in this study were trace producers of phytoliths. A paleoenvironmental reconstruction from fossil phytoliths recovered ...


Us Food Security And Climate Change: Agricultural Futures, Eugene Takle, David Gustafson, Roger Beachy, Gerald C. Nelson, Daniel Mason-D’Croz, Amanda Palazzo Jan 2013

Us Food Security And Climate Change: Agricultural Futures, Eugene Takle, David Gustafson, Roger Beachy, Gerald C. Nelson, Daniel Mason-D’Croz, Amanda Palazzo

Agronomy Publications

Agreement is developing among agricultural scientists on the emerging inability of agriculture to meet growing global food demands. Changes in trends of weather conditions projected by global climate models will challenge physiological limits of crops and exacerbate the global food challenge by 2050. These climate- and constraint-driven crop production challenges are interconnected within a complex global economy, where diverse factors add to price volatility and food scarcity. Our scenarios of the impact of climate change on food security through 2050 for internationally traded crops show that climate change does not threaten near-term US food security due to the availability of ...