{"id":624,"date":"2015-07-29T18:43:08","date_gmt":"2015-07-29T18:43:08","guid":{"rendered":"http:\/\/lab.devnyc.org\/?page_id=624"},"modified":"2020-12-01T16:52:32","modified_gmt":"2020-12-01T20:52:32","slug":"research","status":"publish","type":"page","link":"https:\/\/web.whoi.edu\/wankel\/research\/","title":{"rendered":"Research"},"content":{"rendered":"<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='av_section_1' class='avia-section main_color avia-section-small avia-no-border-styling avia-full-stretch av-parallax-section av-section-color-overlay-active avia-bg-style-parallax  container_wrap fullsize'  data-section-bg-repeat='stretch' ><div class='av-parallax  avia-full-stretch' data-avia-parallax-ratio='0.3' style = 'background-repeat: no-repeat; background-image: url(https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2015\/02\/placeholder-home-bg-1070x430.jpg); background-attachment: scroll; background-position: bottom center; ' ><\/div><div class='av-section-color-overlay-wrap'><div class='av-section-color-overlay' style='opacity: 0.7; background-color: #22476e; '><\/div><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div class=\"flex_column av_one_fifth  flex_column_div first  \" ><\/div><div class=\"flex_column av_three_fifth  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><p><div style='padding-bottom:10px;color:#ffffff;font-size:40px;' class='av-special-heading av-special-heading-h1 custom-color-heading blockquote modern-quote modern-centered  av-inherit-size'><h1 class='av-special-heading-tag'  itemprop=\"headline\"  >Research<\/h1><div class='special-heading-border'><div class='special-heading-inner-border' style='border-color:#ffffff'><\/div><\/div><\/div><br \/>\n<div style='height:30px' class='hr hr-invisible '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div><\/p><\/div><div class=\"flex_column av_one_fifth  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><\/div>\n\n<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><\/div><div class='clear'><\/div><div id='sub_menu1' class='av-submenu-container main_color  av-sticky-submenu container_wrap fullsize'   style='z-index:301'><div class='container av-menu-mobile-disabled '><ul id='av-custom-submenu-1' class='av-subnav-menu av-submenu-pos-center'>\n<li class='menu-item menu-item-top-level  menu-item-top-level-1'><a href='#research-interests' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>Research Interests<\/span><\/a><\/a><\/li>\n<li class='menu-item menu-item-top-level  menu-item-top-level-2'><a href='#coastal-n2o' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>Costal N2O<\/span><\/a><\/a><\/li>\n<li class='menu-item menu-item-top-level  menu-item-top-level-3'><a href='#nitrogen-iron' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>Nitrogen-Iron<\/span><\/a><\/a><\/li>\n<li class='menu-item menu-item-top-level  menu-item-top-level-4'><a href='#hydrothermal' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>Hydrothermal Vents<\/span><\/a><\/a><\/li>\n<li class='menu-item menu-item-top-level  menu-item-top-level-5'><a href='#manganese-oxides' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>Manganese Oxides<\/span><\/a><\/a><\/li>\n<li class='menu-item menu-item-top-level  menu-item-top-level-6'><a href='#in-situ' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>In-Situ Sensors and Instrumentation<\/span><\/a><\/a><\/li>\n<li class='menu-item menu-item-top-level  menu-item-top-level-7'><a href='#deep-biosphere' ><span class='avia-bullet'><\/span><span class='avia-menu-text'>Deep Biosphere<\/span><\/a><\/a><\/li>\n<\/ul><\/div><\/div><div class='sticky_placeholder'><\/div>\n<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><\/div><div id='research-interests' class='avia-section main_color avia-section-default avia-no-shadow avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h1  blockquote modern-quote modern-centered  '><h1 class='av-special-heading-tag'  itemprop=\"headline\"  >Overarching Research Interests<\/h1><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling- av-hover-grow noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.5; background-color:#000000; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#ffffff; '><p>Stable Isotope Biogeochemistry<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2016\/07\/cam1_20150516163058-300x169.jpg' alt='' title='cam1_20150516163058'   itemprop=\"contentURL\"  \/><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Research in the Wankel lab seeks to build a mechanistic understanding of the biogeochemical cycling of N, C and O, by asking how physical, chemical and biological drivers of elemental turnover are integrated and reflected in their natural abundance stable isotopic composition. A major focus of our work also aims to disentangle the complexity of overlapping zonation (&#8220;Redox Real Estate&#8221;) and interactions among elemental transformations along environmental gradients, including specific interactions with cycles of other redox-active elements such as sulfur (S), iron (Fe) and manganese (Mn). We are particularly interested in disentangling the relative importance of biotic and abiotic interactions, including contributions of specific groups of organisms (fungi vs. bacteria vs. archaea) driving N transformations. Therefore, we can be found studying N, C, and O cycling across a variety of marine environments, ranging from tropical coastlines to deep-sea ecosystems, with significant emphasis on dynamics of climatically active trace gases nitrous oxide (N<sub>2<\/sub>O), methane (CH<sub>4<\/sub>) and carbon dioxide (CO<sub>2<\/sub>). We are also continuously working to bring new and experimental tools to bear on these questions, including novel isotope systems and approaches as well as development of cutting-edge technologies for field deployment and underwater measurements.<\/p>\n<\/div><\/section><\/div><\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='coastal-n2o' class='avia-section main_color avia-section-default avia-no-border-styling avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;color:#4326d3;' class='av-special-heading av-special-heading-h1 custom-color-heading blockquote modern-quote modern-centered  '><h1 class='av-special-heading-tag'  itemprop=\"headline\"  >Areas of Active Research<\/h1><div class='special-heading-border'><div class='special-heading-inner-border' style='border-color:#4326d3'><\/div><\/div><\/div>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h2  blockquote modern-quote modern-centered  '><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >Nitrous Oxide Dynamics in Coastal Ecosystems<\/h2><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling- av-hover-grow noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><a href='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2015\/02\/placeholder-home-bg-1030x772.jpg' class='avia_image'  ><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.3; background-color:#f2f2f2; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#ffffff; '><p>Coastal ecosystems &#8211; source or sink?<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2015\/02\/placeholder-home-bg-300x225.jpg' alt='' title='Woodneck Marsh'  itemprop=\"contentURL\"  \/><\/a><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Atmospheric levels of nitrous oxide (N<sub>2<\/sub>O), one of the most radiatively important greenhouse gases, are steadily increasing. Yet predicting patterns of emission in natural systems remains highly speculative and very difficult. Marine ecosystems comprise a large component of the global N<sub>2<\/sub>O atmospheric flux, with coastal zones and estuaries being important contributors to atmospheric N<sub>2<\/sub>O. In the face of the widespread environmental change predicted to occur in global coastal ecosystems over the following decades, changes in N<sub>2<\/sub>O emissions have significant implications for climate forcing. Nevertheless\u00a0there exists a wide range of estimates of N<sub>2<\/sub>O fluxes to the atmosphere and future projections of N<sub>2<\/sub>O production and emission are confounded by extreme spatial and temporal variability of biological sources and sinks (biogeochemical processes). We are working on innovative\u00a0ways of improving our understanding of the dynamics and interplay of these processes and how they act to regulate N<sub>2<\/sub>O flux to (or from) the atmosphere. <span style=\"text-decoration: underline\"><a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/evidence-for-fungal-and-chemodenitrification-based-n2o-flux-from-nitrogen-impacted-coastal-sediments\/\">Central among these approaches are multi-element stable isotopic analyses of N2O and a variety of its precursors &#8211; including novel triple oxygen isotope and intra-molecular site preference measurements.<\/a><\/span><\/p>\n<\/div><\/section><\/div>\n<\/p>\n<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='nitrogen-iron' class='avia-section main_color avia-section-default avia-no-border-styling avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h2  blockquote modern-quote modern-centered  '><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >Redox Interactions between Nitrogen and Metals (Fe, Mn)<\/h2><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling-  noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.3; background-color:#f2f2f2; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#ede331; '><p>Overlapping redox real-estate of N and metal cycling<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2016\/07\/20130815_0149-e1467404752855-225x300.jpg' alt='' title='20130815_0149'   itemprop=\"contentURL\"  \/><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Our lab aims to quantify interactions between the N and those of redox metals (Fe and Mn) cycling in the sediments through a comprehensive examination of the biotic and abiotc interactions between NO<sub>3<\/sub><sup>&#8211;<\/sup> (and NO<sub>2<\/sub><sup>&#8211;<\/sup>) and Fe\/Mn and their influence on the dual isotopic composition (e.g., \u03b4<sup>15<\/sup>N and \u03b4<sup>18<\/sup>O) of NO<sub>3<\/sub><sup>&#8211;<\/sup> in the environment. Specifically, there is a fundamental discrepancy of coupled N and O isotope effects (<sup>18<\/sup>e:<sup>15<\/sup>e) between culture-based isotopic studies of denitrification and field-based isotopic measurements of groundwater NO3- loss under anaerobic conditions (in which denitrification has been widely implicated). This discrepancy may be related to the ubiquitous, yet largely unrecognized, coupling of abiotic and\/or biotic Fe cycling with both reductive and anaerobic oxidative N cycling pathways. Work has focused on <span style=\"text-decoration: underline\"><a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/constraining-the-role-of-iron-in-environmental-nitrogen-transformations-dual-stable-isotope-systematics-of-abiotic-no2%e2%88%92-reduction-by-feii-and-its-production-of-n2o\/\">characterizing abiotic reduction<\/a><\/span> of NO<sub>3<\/sub><sup>&#8211;<\/sup>\u00a0and NO<sub>2<\/sub><sup>&#8211;<\/sup> by ferrous iron (&#8216;chemodenitrification&#8217;) in a variety of binding contexts &#8211; including aqueous iron (complexed and uncomplexed), <span style=\"text-decoration: underline\"><a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/a-dual-nitrite-isotopic-investigation-of-chemodenitrification-by-mineral-associated-feii-and-its-production-of-nitrous-oxide\/\">mineral surface bound iron, iron oxy-hydroxide minerals and iron bound in common clay minerals<\/a><\/span>. Results suggest rapid reduction under some conditions and high levels of N<sub>2<\/sub>O production &#8211; linking these processes to the production of climate dynamics especially in nitrogen\/iron rich environments such as <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/evidence-for-fungal-and-chemodenitrification-based-n2o-flux-from-nitrogen-impacted-coastal-sediments\/\"><span style=\"text-decoration: underline\">coastal and shelf sediments<\/span>.<\/a> A more recent isotopic study of ours demonstrates how ligand-bound Mn(III) may play a role in the <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/an-isotopic-investigation-of-nitrite-oxidation-by-ligand-bound-mniii\/\">abiotic oxidation of nitrite to nitrate &#8211; even under functionally anoxic conditions<\/a> (NSF Low Temperature Geochemistry and Geobiology)<\/p>\n<\/div><\/section><\/div><\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='deep-biosphere' class='avia-section main_color avia-section-default avia-no-border-styling avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h2  blockquote modern-quote modern-centered  '><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >Nitrogen Cycling in the Deep Biosphere<\/h2><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling-  noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.3; background-color:#f2f2f2; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#17486d; '><p>Nitrogen cycling in deep ocean sediments and crust<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2016\/07\/cam2_20150516163022-300x169.jpg' alt='' title='cam2_20150516163022'   itemprop=\"contentURL\"  \/><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Nitrogen (N) is a key component of fundamental biomolecules. Hence, the cycling and availability of N is a central factor governing the extent of ecosystems across the Earth.\u00a0Although hosting the largest habitable environment on the planet, the deep marine biosphere, including those environments below the seafloor in sediments and within the ocean crust, remain poorly understood &#8211; in particular with respect to the sources and cycling of nitrogen that sustain these microbial communities.<\/p>\n<p>In the ocean crust &#8211; warm fluids move quickly through permeable basalt &#8211; allowing the delivery of nutrients and electron acceptors and donors necessary for sustaining life. We\u00a0are collaborating with several groups that are sampling crustal fluids in a variety of contexts (hydrothermal vents, off-axis boreholes, volcanoes etc.) in order to better understand the nature of nitrogen transformations in these under-explored reaches of our planet.<\/p>\n<p>In the organic-lean sediment porewaters underlying the vast expanses of the oligotrophic ocean, where low levels of microbial activity persist despite limited organic matter delivery from overlying water, the extent and modes of nitrogen transformations have not been widely investigated. We are interested in determining what nitrogen sources are available and what nitrogen transformations and metabolisms are active in\u00a0<span style=\"line-height: 1.5\">these remote and &#8216;extreme&#8217; environments. To answer these questions, we have been measuring the N and O\u00a0isotopes of nitrate and nitrite in<span style=\"text-decoration: underline\"> <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/nitrogen-cycling-in-the-subsurface-biosphere-nitrate-isotopes-in-porewaters-underlying-the-oligotrophic-north-atlantic\/\">porewaters of the North Atlantic<\/a> <\/span>and developing a predictive<span style=\"text-decoration: underline\"> <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/isotopic-constraints-on-nitrogen-transformation-rates-in-the-deep-sedimentary-biosphere\/\">reaction-diffusion model<\/a> <\/span>for constraining rates and modes of key nitrogen transformations.\u00a0Our findings indicate that the production of organic matter by in situ autotrophy (e.g., nitrification, nitrogen fixation) supplies a large fraction of the biomass and organic substrate for heterotrophy in these sediments, supplementing the small organic matter pool derived from the overlying euphotic zone. (Center for Dark Energy Biosphere Investigations)<\/span><\/p>\n<\/div><\/section><\/div>\n<\/p>\n<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='manganese-oxides' class='avia-section main_color avia-section-default avia-no-border-styling avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h2  blockquote modern-quote modern-centered  '><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >Isotope Dynamics of Manganese Oxidation<\/h2><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling-  noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.3; background-color:#f2f2f2; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#f7ed33; '><p>Mn oxides harbor links to oxygen sources and cycling<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2015\/07\/Mn-Nodule-Cross-Section-300x225.jpg' alt='' title='Mn Nodule Cross Section'   itemprop=\"contentURL\"  \/><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Manganese oxides are extremely common and geographically widespread in marine environments, exceeding 50% coverage of the seafloor in some abyssal regions of the global ocean. Manganese(II) oxidation by O<sub>2<\/sub> can be facilitated by biological or abiotic processes, including enzyme catalysis, surface and ligand complexation, or reactive oxygen species (ROS) of various origins. Lead by JP student Kevin Sutherland, our study of synthetic manganese (Mn) oxy(hydr)oxide minerals suggests they <span style=\"text-decoration: underline\"><a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/oxygen-isotope-analysis-of-bacterial-and-fungal-manganese-oxides\/\">capture and retain oxygen atoms<\/a> <\/span>from dissolved O<sub>2<\/sub> during oxidation of aqueous Mn(II) to insoluble Mn(III\/IV). We have also investigated the nature of the oxygen isotope composition of naturally occurring manganese oxides as a recorder of oxidation mechanism and oxygen source composition. Our results have shed light on <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/ferromanganese-crusts-as-recorders-of-marine-dissolved-oxygen\/\">dissolved oxygen signals captured in ferromanganese crusts<\/a>, their <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/spectroscopic-insights-into-ferromanganese-crust-formation-and-diagenesis\/\">formation and diagenesis<\/a>, as well as connections to the <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/the-ocean-oxygen-budget-revisited-new-consideration-of-dark-extracellular-superoxide-production\/\">global oxygen cycle<\/a> (NASA Exobiology).<\/p>\n<\/div><\/section><\/div>\n\n<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='in-situ' class='avia-section main_color avia-section-default avia-no-border-styling avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h2  blockquote modern-quote modern-centered  '><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >In-Situ Geochemical Instrumentation<\/h2><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling-  noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.3; background-color:#f2f2f2; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#ffffff; '><p>Bringing the lab to the seafloor with in situ sensor development and applications<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2015\/07\/20140925_0198-300x225.jpg' alt='' title='20140925_0198'   itemprop=\"contentURL\"  \/><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Towards the goal of improving our understanding of the role of the deep ocean in global biogeochemical cycling, we are actively developing in situ chemical and isotopic analytical instrumentation that can be used for making in situ measurements at depth. We use a range of technologies including <a href=\"http:\/\/web.whoi.edu\/wankel\/portfolio-item\/influence-of-subsurface-biosphere-on-geochemical-fluxes-from-diffuse-hydrothermal-fluids\/\">in situ mass <span style=\"text-decoration: underline\">spectrometry<\/span><\/a> and <span style=\"text-decoration: underline\"><a href=\"http:\/\/web.whoi.edu\/wankel\/portfolio-item\/characterizing-the-distribution-of-methane-sources-and-cycling-in-the-deep-sea-via-in-situ-stable-isotope-analysis\/\">in situ laser spectroscopy<\/a><\/span> for detecting and quantifying active microbial cycling of key compounds including molecular<span style=\"text-decoration: underline\"> <a href=\"http:\/\/web.whoi.edu\/wankel\/portfolio-item\/influence-of-subsurface-biosphere-on-geochemical-fluxes-from-diffuse-hydrothermal-fluids\/\">hydrogen<\/a><\/span>, <span style=\"text-decoration: underline\"><a href=\"http:\/\/web.whoi.edu\/wankel\/portfolio-item\/new-constraints-on-methane-fluxes-and-rates-of-anaerobic-methane-oxidation-in-a-gulf-of-mexico-brine-pool-via-in-situ-mass-spectrometry\/\">methane<\/a><\/span> and <a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/in-situ-carbon-isotope-exploration-of-an-active-submarine-volcano\/\"><span style=\"text-decoration: underline\">ca<\/span>rbon dioxide<\/a> and <span style=\"text-decoration: underline\"><a href=\"https:\/\/web.whoi.edu\/wankel\/portfolio-item\/development-of-a-handheld-submersible-chemiluminescent-sensor-quantification-of-superoxide-at-coral-surfaces\/\">reactive oxygen species<\/a><\/span>. We regularly work with WHOI engineering teams to refine these technologies &#8211; deploying them on a variety of submersible platforms including the ROVs <em>Ventana<\/em> (MBARI), <em>Jason<\/em> (WHOI), <em>SuBastian<\/em>\u00a0(Schmidt Ocean Inst) and <em>Hercules<\/em> (Ocean Exploration Trust) as well as the human occupied vehicle DSV <em>Alvin<\/em> (WHOI). (NOAA OER, Ocean Exploration Trust, NSF-Ocean Technology and Interdisciplinary Coordination)<\/p>\n<\/div><\/section><\/div>\n\n<\/div><\/div><\/div><!-- close content main div --><\/div><\/div><div id='hydrothermal' class='avia-section main_color avia-section-default avia-no-border-styling avia-bg-style-scroll  container_wrap fullsize'   ><div class='container' ><div class='template-page content  av-content-full alpha units'><div class='post-entry post-entry-type-page post-entry-624'><div class='entry-content-wrapper clearfix'>\n<div style='padding-bottom:10px;' class='av-special-heading av-special-heading-h2  blockquote modern-quote modern-centered  '><h2 class='av-special-heading-tag'  itemprop=\"headline\"  >Nitrogen Sources and Cycling in Hydrothermal Vent Fluids<\/h2><div class='special-heading-border'><div class='special-heading-inner-border' ><\/div><\/div><\/div>\n<div  class='hr hr-short hr-center '><span class='hr-inner ' ><span class='hr-inner-style'><\/span><\/span><\/div>\n<div class=\"flex_column av_one_third  flex_column_div av-zero-column-padding first  \" style='border-radius:0px; '><div class='avia-image-container  av-styling-  noHover  av-overlay-on-hover  avia-align-center '  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/ImageObject\"  ><div class='avia-image-container-inner'><div class='av-image-caption-overlay'><div class='av-caption-image-overlay-bg' style='opacity:0.3; background-color:#f2f2f2; '><\/div><div class='av-image-caption-overlay-position'><div class='av-image-caption-overlay-center' style='color:#f7ed33; '><p>Nitrogen turnover in hydrothermal systems<\/p>\n<\/div><\/div><\/div><img class='avia_image ' src='https:\/\/web.whoi.edu\/wankel\/wp-content\/uploads\/sites\/45\/2015\/07\/6a00d8341bf7f753ef01347fd5dfb2970c-min-e1438097676803-300x119.jpg' alt='' title='Hydrothemal'   itemprop=\"contentURL\"  \/><\/div><\/div><\/div><div class=\"flex_column av_two_third  flex_column_div av-zero-column-padding   \" style='border-radius:0px; '><section class=\"av_textblock_section\"  itemscope=\"itemscope\" itemtype=\"https:\/\/schema.org\/CreativeWork\" ><div class='avia_textblock '   itemprop=\"text\" ><p>Although hydrothermally hosted transformations of nitrogen-bearing compounds have been shown to play potentially central roles in the production of pre-biotic compounds on early Earth and possibly other planets, the mechanisms at work and controls thereupon remain unclear. Furthermore, despite the widespread use of stable nitrogen isotopic composition for distinguishing among N sources and reaction pathways, a comprehensive understanding of the underlying stable isotope systematics of these transformations under hydrothermal conditions is sorely lacking. Specifically, the reduction of oxidized nitrogen compounds such as NO<sub>3<\/sub><sup>&#8211;<\/sup>, NO<sub>2<\/sub><sup>&#8211;<\/sup> and N<sub>2<\/sub> to the reduced form NH<sub>4<\/sub><sup>+<\/sup>, although shown to be viable reactions under sufficiently reducing conditions, may occur as either unidirectional reactions where kinetically uninhibited or as equilibrium reactions driving composition toward an equilibrium isotopic distribution. (NSF Marine Geology and Geophysics)<\/p>\n<\/div><\/section><\/div>\n\n","protected":false},"excerpt":{"rendered":"","protected":false},"author":110,"featured_media":0,"parent":0,"menu_order":0,"comment_status":"open","ping_status":"open","template":"","meta":[],"_links":{"self":[{"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/pages\/624"}],"collection":[{"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/pages"}],"about":[{"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/types\/page"}],"author":[{"embeddable":true,"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/users\/110"}],"replies":[{"embeddable":true,"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/comments?post=624"}],"version-history":[{"count":3,"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/pages\/624\/revisions"}],"predecessor-version":[{"id":1153,"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/pages\/624\/revisions\/1153"}],"wp:attachment":[{"href":"https:\/\/web.whoi.edu\/wankel\/wp-json\/wp\/v2\/media?parent=624"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}