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Full-Text Articles in Life Sciences
Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones
Watching Grass Grow: How Soil Moisture Affects Vesicular-Arbuscular Mycorrhizae And Growth In Little Bluestem, Laura M. Jones
Honors Scholar Theses
Vesicular-arbuscular mycorrhizae (VAM) are an ancient mutualism in which soil-dwelling fungi enhance plant absorption of phosphorus and nitrogen in exchange for photosynthates. VAM are sensitive to changes in soil moisture and nutrient content, fluctuating between mutualism and parasitism depending on conditions of drought stress and nutrient deficiency. Understanding how VAM respond to precipitation changes is crucial for both conservation and agricultural purposes. To test how soil moisture changes the effects of VAM colonization and growth in little bluestem (Schizachyrium scoparium), a common prairie grass, I planted 300 seeds in a greenhouse in sterilized soil and soil inoculated with …
Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith
Changes In The Diet And Body Size Of A Small Herbivorous Mammal (Hispid Cotton Rat, Sigmodon Hispidus) Following The Late Pleistocene Megafauna Extinction, Catalina P. Tomé, Emma A. Elliott Smith, S. Kathleen Lyons, Seth D. Newsome, Felisa A. Smith
School of Biological Sciences: Faculty Publications
The catastrophic loss of large-bodied mammals during the terminal Pleistocene likely led to cascading effects within communities. While the extinction of the top consumers probably expanded the resources available to survivors of all body sizes, little work has focused on the responses of the smallest mammals. Here, we use a detailed fossil record from the southwestern United States to examine the response of the hispid cotton rat Sigmodon hispidus to biodiversity loss and climatic change over the late Quaternary. In particular, we focus on changes in diet and body size. We characterize diet through carbon (δ13C) and nitrogen …
Iceland's Migratory Birds In Changing Environmental Conditions: An Interactive Synthesis, Frances J. Duncan
Iceland's Migratory Birds In Changing Environmental Conditions: An Interactive Synthesis, Frances J. Duncan
Independent Study Project (ISP) Collection
Human-driven changes to environmental conditions alter the habitats, behaviors, and migration patterns of migratory species. Changes in temperature, vegetation, and precipitation are just some of the factors contributing to shifts in phenology, demography, and distribution of migratory birds. These changes are driven by anthropogenic climate change and amplified by human land-use change, and are especially intense at high latitudes. This project creatively communicates the effects of environmental changes on three species of migratory birds in Iceland—the northern wheatear, the Greenland white-fronted goose, and the black-tailed godwit—using principles of storytelling and game design. The resulting interactive product is a game that …
Abundance And Species Diversity Hotspots Of Tracked Marine Predators Across The North American Arctic, David J. Yurkowski, Marie Auger-Méthé, Mark L. Mallory, Sarah N.P. Wong, Grant Gilchrist, Andrew E. Derocher, Evan Richardson, Nicholas J. Lunn, Nigel E. Hussey, Marianne Marcoux, Ron R. Togunov, Aaron T. Fisk, Lois A. Harwood, Rune Dietz, Aqqalu Rosing-Asvid, Erik W. Born, Anders Mosbech, Jérôme Fort, David Grémillet, Lisa Loseto
Abundance And Species Diversity Hotspots Of Tracked Marine Predators Across The North American Arctic, David J. Yurkowski, Marie Auger-Méthé, Mark L. Mallory, Sarah N.P. Wong, Grant Gilchrist, Andrew E. Derocher, Evan Richardson, Nicholas J. Lunn, Nigel E. Hussey, Marianne Marcoux, Ron R. Togunov, Aaron T. Fisk, Lois A. Harwood, Rune Dietz, Aqqalu Rosing-Asvid, Erik W. Born, Anders Mosbech, Jérôme Fort, David Grémillet, Lisa Loseto
Great Lakes Institute for Environmental Research Publications
Aim: Climate change is altering marine ecosystems worldwide and is most pronounced in the Arctic. Economic development is increasing leading to more disturbances and pressures on Arctic wildlife. Identifying areas that support higher levels of predator abundance and biodiversity is important for the implementation of targeted conservation measures across the Arctic. Location: Primarily Canadian Arctic marine waters but also parts of the United States, Greenland and Russia. Methods: We compiled the largest data set of existing telemetry data for marine predators in the North American Arctic consisting of 1,283 individuals from 21 species. Data were arranged into four species groups: …
Composition And Ecology Of Avian Communities Along Elevational Gradients In Borneo, Ryan Christian Burner
Composition And Ecology Of Avian Communities Along Elevational Gradients In Borneo, Ryan Christian Burner
LSU Doctoral Dissertations
A primary goal of ecology is to explain the diversity and distribution of organisms. Species distributions can be a function of abiotic factors, species interactions, dispersal limitations, and history, but the relative importance of these factors is widely debated. Elevational gradients are useful systems for studying these effects because many of these factors vary predictably with elevation, and because elevational gradients are replicated many times across the earth. However, few quantitative surveys of Southeast Asian bird communities have been conducted along elevational gradients. In this study, I surveyed birds using point counts and measured habitat and temperature across primary forest …
Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler
Shade Trees Preserve Avian Insectivore Biodiversity On Coffee Farms In A Warming Climate, Sarah L. Schooler
Cal Poly Humboldt theses and projects
Coffee is an important export in many developing countries, with a global annual trade value of $100 billion. Climate change is projected to drastically reduce the area where coffee is able to be grown. Shade trees may mitigate the effects of climate change through temperature regulation for coffee growth, temperature regulation for pest control, and increase in pest-eating bird diversity. The impact of shade on bird diversity and microclimate on coffee farms has been studied extensively in the Neotropics, but there is a dearth of research in the Paleotropics. I examined the local effects of shade on bird presence and …
A Multi-Scale Analysis Of Jaguar (Panthera Onca) And Puma (Puma Concolor) Habitat Selection And Conservation In The Narrowest Section Of Panama., Kimberly A. Craighead
A Multi-Scale Analysis Of Jaguar (Panthera Onca) And Puma (Puma Concolor) Habitat Selection And Conservation In The Narrowest Section Of Panama., Kimberly A. Craighead
Antioch University Dissertations & Theses
Over the past two centuries, large terrestrial carnivores have suffered extreme population declines and range contractions resulting from the synergistic anthropogenic threats of land-use change and indirect effects of climate change. In Panama, rapid land use conversion coupled with climate change is predicted to negatively impact jaguar (Panthera onca) and puma (Puma concolor). This dissertation examined the environmental variables and scales influencing jaguar and puma habitat selection by season (annual, wet, and dry), using multi-scale optimized habitat suitability models and a machine-learning algorithm (Random Forests), in the narrowest section of Panama. The models derived from the data of an intensive …