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School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Series

Biogeochemistry

Publication Year

Articles 1 - 5 of 5

Full-Text Articles in Physical Sciences and Mathematics

Sulfur Cycling Connects Microbiomes And Biogeochemistry In Deep-Sea Hydrothermal Plumes, Zhichao Zhou, Patricia Q. Tran, Alyssa M. Adams, Kristopher Kieft, John A. Breier, Caroline S. Fortunato, Cody S. Sheik, Julie A. Huber, Meng Li, Gregory J. Dick, Karthik Anantharaman Aug 2023

Sulfur Cycling Connects Microbiomes And Biogeochemistry In Deep-Sea Hydrothermal Plumes, Zhichao Zhou, Patricia Q. Tran, Alyssa M. Adams, Kristopher Kieft, John A. Breier, Caroline S. Fortunato, Cody S. Sheik, Julie A. Huber, Meng Li, Gregory J. Dick, Karthik Anantharaman

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

In globally distributed deep-sea hydrothermal vent plumes, microbiomes are shaped by the redox energy landscapes created by reduced hydrothermal vent fluids mixing with oxidized seawater. Plumes can disperse over thousands of kilometers and their characteristics are determined by geochemical sources from vents, e.g., hydrothermal inputs, nutrients, and trace metals. However, the impacts of plume biogeochemistry on the oceans are poorly constrained due to a lack of integrated understanding of microbiomes, population genetics, and geochemistry. Here, we use microbial genomes to understand links between biogeography, evolution, and metabolic connectivity, and elucidate their impacts on biogeochemical cycling in the deep sea. Using …


In-Depth Analysis Of N2o Fluxes In Tropical Forest Soils Of The Congo Basin Combining Isotope And Functional Gene Analysis, Nora Gallarotti, Matti Barthel, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Marijn Bauters, Simon Baumgartner, Travis W. Drake, Pascal Boeckx, Joachim Mohn, Manon Longepierre May 2021

In-Depth Analysis Of N2o Fluxes In Tropical Forest Soils Of The Congo Basin Combining Isotope And Functional Gene Analysis, Nora Gallarotti, Matti Barthel, Elizabeth Verhoeven, Engil Isadora Pujol Pereira, Marijn Bauters, Simon Baumgartner, Travis W. Drake, Pascal Boeckx, Joachim Mohn, Manon Longepierre

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Primary tropical forests generally exhibit large gaseous nitrogen (N) losses, occurring as nitric oxide (NO), nitrous oxide (N2O) or elemental nitrogen (N2). The release of N2O is of particular concern due to its high global warming potential and destruction of stratospheric ozone. Tropical forest soils are predicted to be among the largest natural sources of N2O; however, despite being the world’s second-largest rainforest, measurements of gaseous N-losses from forest soils of the Congo Basin are scarce. In addition, long-term studies investigating N2O fluxes from different forest ecosystem types (lowland and montane forests) are scarce. In this study we show that …


The Simulated Biological Response To Southern Ocean Eddies Via Biological Rate Modification And Physical Transport, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney Apr 2020

The Simulated Biological Response To Southern Ocean Eddies Via Biological Rate Modification And Physical Transport, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We examine the structure and drivers of anomalous phytoplankton biomass in Southern Ocean eddies tracked in a global, multiyear, eddy-resolving, 3-D ocean simulation of the Community Earth System Model.We examine how simulated anticyclones and cyclones differentially modify phytoplankton biomass concentrations, growth rates, and physical transport. On average, cyclones induce negative division rate anomalies that drive negative net population growth rate anomalies, reduce dilution across shallower mixed layers, and advect biomass anomalously downward via eddy-induced Ekman pumping. The opposite is true in anticyclones. Lateral transport is dominated by eddy stirring rather than eddy trapping. The net effect on anomalous biomass can …


Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney Apr 2020

Eddy-Modified Iron, Light, And Phytoplankton Cell Division Rates In The Simulated Southern Ocean, Tyler Rohr, Cheryl S. Harrison, Matthew C. Long, Peter Gaube, Scott C. Doney

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

We examine the effects of Southern Ocean eddies on phytoplankton cell division rates in a global, multiyear, eddy‐resolving, 3‐D ocean simulation of the Community Earth System Model. We first identify and track eddies in the simulation and validate their distribution and demographics against observed eddy trajectory characteristics. Next, we examine how simulated cyclones and anticyclones differentially modify iron, light, and ultimately population‐specific cell division rates. We use an eddy‐centric, depth‐averaged framework to explicitly examine the dynamics of the phytoplankton population across the entire water column within an eddy. We find that population‐averaged iron availability is elevated in anticyclones throughout the …


Increasing Impacts Of Extreme Droughts On Vegetation Productivity Under Climate Change, Chonggang Xu, Nate G. Mcdowell, Rosie A. Fisher, Liang Wei, Sanna Sevanto, Bradley O. Christoffersen, Engsheng Weng, Richard S. Middleton Nov 2019

Increasing Impacts Of Extreme Droughts On Vegetation Productivity Under Climate Change, Chonggang Xu, Nate G. Mcdowell, Rosie A. Fisher, Liang Wei, Sanna Sevanto, Bradley O. Christoffersen, Engsheng Weng, Richard S. Middleton

School of Earth, Environmental, and Marine Sciences Faculty Publications and Presentations

Terrestrial gross primary production (GPP) is the basis of vegetation growth and food production globally1 and plays a critical role in regulating atmospheric CO2 through its impact on ecosystem carbon balance. Even though higher CO2 concentrations in future decades can increase GPP2, low soil water availability, heat stress and disturbances associated with droughts could reduce the benefits of such CO2 fertilization. Here we analysed outputs of 13 Earth system models to show an increasingly stronger impact on GPP by extreme droughts than by mild and moderate droughts over the twenty-first century. Due to a dramatic increase in …