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Full-Text Articles in Physical Sciences and Mathematics
Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty
Early Paleogene Biosiliceous Sedimentation In The Atlantic Ocean: Testing The Inorganic Origin Hypothesis For Paleocene And Eocene Chert And Porcellanite, Jakub Witkowski, Donald E. Penman, Karolina Bryłka, Bridget S. Wade, Sabine Matting, David M. Harwood, Steven M. Bohaty
Department of Earth and Atmospheric Sciences: Faculty Publications
The widespread occurrence of lower Eocene chert and porcellanite has been viewed as a major paleoceanographic issue since the advent of ocean drilling, and both biotic and abiotic forcings have been proposed to explain it. We present a reconstruction of indurated siliceous sediment (ISS) and preserved biosiliceous sediment (PBS) occurrences in the Atlantic Ocean through the Paleocene and Eocene (~66 through 34 Ma). ISS and PBS distributions reveal dissimilar temporal trends, with the peak of ISS occurrences coinciding with the Early Eocene Climatic Optimum, in line with previous studies. PBS occurrences show a generally increasing trend culminating between 44 and …
Assessing The Hierarchy Of Long-Term Environmental Controls On Diatom Communities Of Yellowstone National Park Using Lacustrine Sediment Records, Victoria Chraibi, Sherilyn C. Fritz
Assessing The Hierarchy Of Long-Term Environmental Controls On Diatom Communities Of Yellowstone National Park Using Lacustrine Sediment Records, Victoria Chraibi, Sherilyn C. Fritz
Department of Earth and Atmospheric Sciences: Faculty Publications
An ecosystem’s ability to maintain structure and function following disturbance, defined as resilience, is influenced by a hierarchy of environmental controls, including climate, surface cover, and ecological relationships that shape biological community composition and productivity. This study examined lacustrine sediment records of naturally fishless lakes in Yellowstone National Park to reconstruct the response of aquatic communities to climate and trophic cascades from fish stocking. Sediment records of diatom algae did not exhibit a distinct response to fish stocking in terms of assemblage or algal productivity. Instead, 3 of 4 lakes underwent a shift to dominance by benthic diatom species from …
Spatial And Temporal Ecological Uniqueness Of Andean Diatom Communities Are Correlated With Climate, Geodiversity And Long-Term Limnological Change, Xavier Benito, Annika Vilmi, Melina Luethje, Maria Laura Carrevedo, Marja Lindholm, Sherilyn C. Fritz
Spatial And Temporal Ecological Uniqueness Of Andean Diatom Communities Are Correlated With Climate, Geodiversity And Long-Term Limnological Change, Xavier Benito, Annika Vilmi, Melina Luethje, Maria Laura Carrevedo, Marja Lindholm, Sherilyn C. Fritz
Department of Earth and Atmospheric Sciences: Faculty Publications
High-elevation tropical lakes are excellent sentinels of global change impacts, such as climate warming, land-use change, and atmospheric deposition. These effects are often correlated with temporal and spatial beta diversity patterns, with some local communities contributing more than others, a phenomenon known as local contribution to beta diversity (LCBD) or ecological uniqueness. Microorganisms, such as diatoms, are considered whole-ecosystem indicators, but little is known about their sensitivity and specificity in beta diversity studies mostly because of the lack of large spatial and temporal datasets. To fill this gap, we used a tropical South American diatom database comprising modern (144 lakes) …