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Full-Text Articles in Life Sciences

New Opportunities And Untapped Scientific Potential In The Abyssal Ocean, Jeffrey J. Marlowe, Rika E. Anderson, Anna-Louise Reysenbach, Jeffrey S. Seewald, Timothy M. Shank, Andreas P. Teske, V. Dorsey Wanless, S. Adam Soule Feb 2022

New Opportunities And Untapped Scientific Potential In The Abyssal Ocean, Jeffrey J. Marlowe, Rika E. Anderson, Anna-Louise Reysenbach, Jeffrey S. Seewald, Timothy M. Shank, Andreas P. Teske, V. Dorsey Wanless, S. Adam Soule

Biology Faculty Publications and Presentations

The abyssal ocean covers more than half of the Earth’s surface, yet remains understudied and underappreciated. In this Perspectives article, we mark the occasion of the Deep Submergence Vehicle Alvin’s increased depth range (from 4500 to 6500 m) to highlight the scientific potential of the abyssal seafloor. From a geologic perspective, ultra-slow spreading mid-ocean ridges, Petit Spot volcanism, transform faults, and subduction zones put the full life cycle of oceanic crust on display in the abyss, revealing constructive and destructive forces over wide ranges in time and space. Geochemically, the abyssal pressure regime influences the solubility of constituents such as …


The Conservation Status Of The World’S Freshwater Molluscs, M. Böhm, N. I. Dewhurst-Richman, M. Seddon, C. Albrecht, D. Allen, A. E. Bogan, K. Cummings, G. Darrigran, W. Darwall, Kathryn E. Perez Jul 2021

The Conservation Status Of The World’S Freshwater Molluscs, M. Böhm, N. I. Dewhurst-Richman, M. Seddon, C. Albrecht, D. Allen, A. E. Bogan, K. Cummings, G. Darrigran, W. Darwall, Kathryn E. Perez

Biology Faculty Publications and Presentations

With the biodiversity crisis continuing unchecked, we need to establish levels and drivers of extinction risk, and reassessments over time, to effectively allocate conservation resources and track progress towards global conservation targets. Given that threat appears particularly high in freshwaters, we assessed the extinction risk of 1428 randomly selected freshwater molluscs using the IUCN Red List Categories and Criteria, as part of the Sampled Red List Index project. We show that close to one-third of species in our sample are estimated to be threatened with extinction, with highest levels of threat in the Nearctic, Palearctic and Australasia and among gastropods. …


Disentangling The Effects Of Vapor Pressure Deficit And Soil Water Availability On Canopy Conductance In A Seasonal Tropical Forest During The 2015 El Niño Drought, Yilin Fang, L. Ruby Leung, Brett T. Wolfe, Matteo Detto, Ryan G. Knox, Bryan Powell, Charlotte Grossiord, Chonggang Xu, Bradley O. Christoffersen, Pierre Gentine May 2021

Disentangling The Effects Of Vapor Pressure Deficit And Soil Water Availability On Canopy Conductance In A Seasonal Tropical Forest During The 2015 El Niño Drought, Yilin Fang, L. Ruby Leung, Brett T. Wolfe, Matteo Detto, Ryan G. Knox, Bryan Powell, Charlotte Grossiord, Chonggang Xu, Bradley O. Christoffersen, Pierre Gentine

Biology Faculty Publications and Presentations

Water deficit in the atmosphere and soil are two key interactive factors that constrain transpiration and vegetation productivity. It is not clear which of these two factors is more important for the water and carbon flux response to drought stress in ecosystems. In this study, field data and numerical modeling were used to isolate their impact on evapotranspiration (ET) and gross primary productivity (GPP) at a tropical forest site in Barro Colorado Island (BCI), Panama, focusing on their response to the drought induced by the El Niño event of 2015–2016. Numerical simulations were performed using a plant hydrodynamic scheme (HYDRO) …


Niche Partitioning Of Low-Light Adapted Prochlorococcus Subecotypes Across Oceanographic Gradients Of The North Pacific Subtropical Front, Anne W. Thompson, Kathleen Kouba, Nathan A. Ahlgren Jan 2021

Niche Partitioning Of Low-Light Adapted Prochlorococcus Subecotypes Across Oceanographic Gradients Of The North Pacific Subtropical Front, Anne W. Thompson, Kathleen Kouba, Nathan A. Ahlgren

Biology Faculty Publications and Presentations

The cyanobacterium Prochlorococcus is the most abundant photosynthetic cell on Earth and contributes to global ocean carbon cycling and food webs. Prochlorococcus is known for its extensive diversity that falls into two groups of ecotypes, the low‐light (LL) and high‐light (HL) adapted ecotypes. Previous work has shown niche partitioning of the very abundant HL adapted ecotypes and subecotypes across oceanographic gradients including temperature, nutrients, and day length. However, niche partitioning of subecotypes within the LL adapted ecotypes has not been studied as well because they are less abundant and less accessible than surface, HL populations. Through high‐throughput, cyanobacterial‐specific, sequencing of …


Dynamics Of Prochlorococcus Diversity And Photoacclimation During Short-Term Shifts In Water Column Stratification At Station Aloha, Anne W. Thompson, Ger Van Den Engh, Nathan A. Ahlgren, Kathleen Kouba, Samantha Ward, Samuel T. Wilson, David M. Karl Dec 2018

Dynamics Of Prochlorococcus Diversity And Photoacclimation During Short-Term Shifts In Water Column Stratification At Station Aloha, Anne W. Thompson, Ger Van Den Engh, Nathan A. Ahlgren, Kathleen Kouba, Samantha Ward, Samuel T. Wilson, David M. Karl

Biology Faculty Publications and Presentations

The cyanobacterium Prochlorococcus is the dominant phototroph in surface waters of the vast oligotrophic oceans, the foundation of marine food webs, and an important component of global biogeochemical cycles. The prominence of Prochlorococcus across the environmental gradients of the open ocean is attributed to its extensive genetic diversity and flexible chlorophyll physiology, enabling light capture over a wide range of intensities. What remains unknown is the balance between temporal dynamics of genetic diversity and chlorophyll physiology in the ability of Prochlorococcus to respond to a variety of short (approximately 1 day) and longer (months to year) changes in the environment. …


A Comparison Of Salinity Effects From Hurricanes Dolly (2008) And Alex (2010) In A Texas Lagoon System, Joseph L. Kowalski, Hudson R. Deyoe, Gilbert H. Boza Jr., Donald L. Hockaday, Paul V. Zimba May 2018

A Comparison Of Salinity Effects From Hurricanes Dolly (2008) And Alex (2010) In A Texas Lagoon System, Joseph L. Kowalski, Hudson R. Deyoe, Gilbert H. Boza Jr., Donald L. Hockaday, Paul V. Zimba

Biology Faculty Publications and Presentations

A comparison of salinity effects from hurricanes Dolly (2008) and Alex (2010) in a Texas lagoon system.Hurricanes are not uncommon along the Gulf of Mexico coast, but there are few studies of the effects they have on coastal embayments. Hurricanes Dolly (2008) and Alex (2010) were both Category 2 storms affecting the Lower Laguna Madre (LLM) of Texas. Surveys were performed to assess poststorm water quality after landfall of both storms at up to 18 sample stations. The main difference between storm effects was salinity reduction because of stormwater input from the watershed. Effects from Hurricane Dolly were of short …


Links From Mantle To Microbe At The Lau Integrated Study Site: Insights From A Back-Arc Spreading Center, Margaret K. Tivey, Erin Becker, Roxanne Beinart, Charles R. Fisher, Peter Girguis, Charles H. Langmuir, Peter J. Michael, Anna-Louise Reysenbach Mar 2012

Links From Mantle To Microbe At The Lau Integrated Study Site: Insights From A Back-Arc Spreading Center, Margaret K. Tivey, Erin Becker, Roxanne Beinart, Charles R. Fisher, Peter Girguis, Charles H. Langmuir, Peter J. Michael, Anna-Louise Reysenbach

Biology Faculty Publications and Presentations

The Lau Integrated Study Site (ISS) has provided unique opportunities for study of ridge processes because of its back-arc setting in the southwestern Pacific. Its location allows study of a biogeographical province distinct from those of eastern Pacific and mid-Atlantic ridges, and crustal compositions along the ridge lie outside the range of mid-ocean ridge crustal compositions. The Lau ISS is located above a subduction zone, at an oblique angle. The underlying mantle receives water and other elements derived from the downgoing lithospheric slab, with an increase in slab influence from north to south. Water lowers the mantle melting temperature and …