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Adrian
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Adrian
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ArticleSynthesis of iron fertilization experiments : from the Iron Age in the Age of Enlightenment(American Geophysical Union, 2005-09-28) Baar, Hein J. W. de ; Boyd, Philip W. ; Coale, Kenneth H. ; Landry, Michael R. ; Tsuda, Atsushi ; Assmy, Philipp ; Bakker, Dorothee C. E. ; Bozec, Yann ; Barber, Richard T. ; Brzezinski, Mark A. ; Buesseler, Ken O. ; Boye, Marie ; Croot, Peter L. ; Gervais, Frank ; Gorbunov, Maxim Y. ; Harrison, Paul J. ; Hiscock, William T. ; Laan, Patrick ; Lancelot, Christiane ; Law, Cliff S. ; Levasseur, Maurice ; Marchetti, Adrian ; Millero, Frank J. ; Nishioka, Jun ; Nojiri, Yukihiro ; van Oijen, Tim ; Riebesell, Ulf ; Rijkenberg, Micha J. A. ; Saito, Hiroaki ; Takeda, Shigenobu ; Timmermans, Klaas R. ; Veldhuis, Marcel J. W. ; Waite, Anya M. ; Wong, Chi-ShingComparison of eight iron experiments shows that maximum Chl a, the maximum DIC removal, and the overall DIC/Fe efficiency all scale inversely with depth of the wind mixed layer (WML) defining the light environment. Moreover, lateral patch dilution, sea surface irradiance, temperature, and grazing play additional roles. The Southern Ocean experiments were most influenced by very deep WMLs. In contrast, light conditions were most favorable during SEEDS and SERIES as well as during IronEx-2. The two extreme experiments, EisenEx and SEEDS, can be linked via EisenEx bottle incubations with shallower simulated WML depth. Large diatoms always benefit the most from Fe addition, where a remarkably small group of thriving diatom species is dominated by universal response of Pseudo-nitzschia spp. Significant response of these moderate (10–30 μm), medium (30–60 μm), and large (>60 μm) diatoms is consistent with growth physiology determined for single species in natural seawater. The minimum level of “dissolved” Fe (filtrate < 0.2 μm) maintained during an experiment determines the dominant diatom size class. However, this is further complicated by continuous transfer of original truly dissolved reduced Fe(II) into the colloidal pool, which may constitute some 75% of the “dissolved” pool. Depth integration of carbon inventory changes partly compensates the adverse effects of a deep WML due to its greater integration depths, decreasing the differences in responses between the eight experiments. About half of depth-integrated overall primary productivity is reflected in a decrease of DIC. The overall C/Fe efficiency of DIC uptake is DIC/Fe ∼ 5600 for all eight experiments. The increase of particulate organic carbon is about a quarter of the primary production, suggesting food web losses for the other three quarters. Replenishment of DIC by air/sea exchange tends to be a minor few percent of primary CO2 fixation but will continue well after observations have stopped. Export of carbon into deeper waters is difficult to assess and is until now firmly proven and quite modest in only two experiments.
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PreprintThe molecular products and biogeochemical significance of lipid photooxidation in West Antarctic surface waters( 2018-04) Collins, James R. ; Fredricks, Helen F. ; Bowman, Jeff S. ; Ward, Collin P. ; Moreno, Carly ; Longnecker, Krista ; Marchetti, Adrian ; Hansel, Colleen M. ; Ducklow, Hugh W. ; Van Mooy, Benjamin A. S.The seasonal depletion of stratospheric ozone over the Southern Hemisphere allows abnormally high doses of ultraviolet radiation (UVR) to reach surface waters of the West Antarctic Peninsula (WAP) in the austral spring, creating a natural laboratory for the study of lipid photooxidation in the shallow mixed layer of the marginal ice zone. The photooxidation of lipids under such conditions has been identified as a significant source of stress to microorganisms, and short-chain fatty acids altered by photochemical processes have been found in both marine aerosols and sinking marine particle material. However, the biogeochemical impact of lipid photooxidation has not been quantitatively compared at ecosystem scale to the many other biological and abiotic processes that can transform particulate organic matter in the surface ocean. We combined results from field experiments with diverse environmental data, including high-resolution, accurate-mass HPLC-ESI-MS analysis of lipid extracts and in situ measurements of ultraviolet irradiance, to address several unresolved questions about lipid photooxidation in the marine environment. In our experiments, we used liposomes — nonliving, cell-like aggregations of lipids — to examine the photolability of various moieties of the intact polar diacylglycerol (IP-DAG) phosphatidylcholine (PC), a structural component of membranes in a broad range of microorganisms. We observed significant rates of photooxidation only when the molecule contained the polyunsaturated fatty acid (PUFA) docosahexaenoic acid (DHA). As the DHA-containing lipid was oxidized, we observed the steady ingrowth of a diversity of oxylipins and oxidized IP-DAG; our results suggest both the intact IPDAG the degradation products were amenable to heterotrophic assimilation. To complement our experiments, we used an enhanced version of a new lipidomics discovery software package to identify the lipids in water column samples and in several diatom isolates. The galactolipid digalactosyldiacylglycerol (DGDG), the sulfolipid sulfoquinovosyldiacylglycerol (SQDG) and the phospholipids PC and phosphatidylglycerol (PG) accounted for the majority of IP-DAG in the water column particulate (≥ 0.2 μm) size fraction; between 3.4 and 5.3 % of the IP-DAG contained fatty acids that were both highly polyunsaturated (i.e., each containing ≥ 5 double bonds). Using a broadband apparent quantum yield (AQY) that accounted for direct and Type I (i.e., radical-mediated) photooxidation of PUFA-containing IP-DAG, we estimated that 0.7 ± 0.2 μmol IP-DAG m-2 d-1 (0.5 ± 0.1 mg C m-2 d-1) were oxidized by photochemical processes in the mixed layer. This rate represented 4.4 % (range, 3-21 %) of the mean bacterial production rate measured in the same waters immediately following the retreat of the sea ice. Because our liposome experiments were not designed to account for oxidation by Type II photosensitized processes that often dominate in marine phytodetritus, our rate estimates may represent a sizeable underestimate of the true rate of lipid photooxidation in the water column. While production of such diverse oxidized lipids and oxylipins has been previously observed in terrestrial plants and mammals in response to biological stressors such as disease, we show here that a similar suite of molecules can be produced via an abiotic process in the environment and that the effect can be commensurate in magnitude with other ecosystem-scale biogeochemical processes.
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Working PaperRoadmap Towards Communitywide Intercalibration and Standardization of Ocean Nucleic Acids ‘Omics Measurements(Woods Hole Oceanographic Institution, 2022-03) Berube, Paul M. ; Gifford, Scott M. ; Hurwitz, Bonnie ; Jenkins, Bethany D. ; Marchetti, Adrian ; Santoro, Alyson E.In January 2020, the US Ocean Carbon & Biogeochemistry (OCB) Project Office funded the Ocean Nucleic Acids 'omics Intercalibration and Standardization workshop held at the University of North Carolina in Chapel Hill. Thirty-two participants from across the US, along with guests from Canada and France, met to develop a framework for standardization and intercalibration (S&I) of ocean nucleic acid ‘omics (na’omics) approaches (i.e., amplicon sequencing, metagenomics and metatranscriptomics). During the three-day workshop, participants discussed numerous topics, including: a) sample biomass collection and nucleic acid preservation for downstream analysis, b) extraction protocols for nucleic acids, c) addition of standard reference material to nucleic acid isolation protocols, d) isolation methods unique to RNA, e) sequence library construction, and f ) integration of bioinformatic considerations. This report provides a summary of these and other topics covered during the workshop and a series of recommendations for future S&I activities for na’omics approaches.
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DatasetDiatom growth rates from samples collected on the Gould cruise LMG1411 in the Western Antarctica Peninsula from 2014 (Polar Transcriptomes project)(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-17) Marchetti, AdrianDiatom growth rates from samples collected on the Gould cruise LMG1411 in the Western Antarctica Peninsula from 2014 (Polar Transcriptomes project) For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/666201
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DatasetDiscrete raw measurements from upwelling experiments conducted on two phytoplankton species isolated from the California Upwelling Zone(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2021-03-17) Marchetti, AdrianTwo phytoplankton species, Chaetoceros decipiens (UNC1416) and Emiliania huxleyi (UNC1419), were cultured at 12 °C in artificial Aquil* medium using trace metal clean (TMC) techniques. Macronutrients were supplied such that nitrate would become limiting for growth (50 μmol L⁻¹ NO3, 10 μmol L⁻¹ PO4, 200 μmol L⁻¹ H4SiO4) and two iron treatments were used (1370 nmol L⁻¹ and 3.1 nmol L⁻¹ total Fe). Upwelling conveyor belt cycle (UCBC) simulations were performed by transitioning the cultures to different nutrient and light regimes. They were grown by first growing the cultures with ample light (115 µmol photons m⁻² s⁻¹) until nitrate depletion and stationary growth. Cultures were then moved to no light for 10 days to simulate the sinking out of the euphotic zone. After this dark period, the cultures were subsequently transferred back to fresh medium under ambient light levels, and grown until stationary phase again. Samples were collected for six different time points associated with the different phases throughout the simulated upwelling cycle. This dataset includes the treatment information, replicate IDs, and the discrete raw measurements made for the upwelling experiments. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/826448
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DatasetMarine Microbial Eukaryote Transcriptome Sequencing Project (MMETSP) location information on samples obtained on Gould (LMG1411) in the Western Antarctica Peninsula during 2014 (Polar Transcriptomes project)(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-17) Marchetti, AdrianMarine Microbial Eukaryote Transcriptome Sequencing Project (MMETSP) location information on samples obtained on Gould (LMG1411) in the Western Antarctica Peninsula during 2014 (Polar Transcriptomes project) For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/665427
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DatasetPresence and absence of iron and light-related functional genes collected on the Gould (LMG1411) cruise in the Western Antarctica Peninsula during 2014 (Polar Transcriptomes project)(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-17) Marchetti, AdrianPresence and absence of iron and light-related functional genes collected on the Gould (LMG1411) cruise in the Western Antarctica Peninsula during 2014 (Polar Transcriptomes project) For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/665407
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DatasetTranscriptome statistics from samples obtained on LMG1411 collected on the Gould (LMG1411) in the Western Antarctica Peninsula in 2014. (Polar Transcriptomes project)(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-18) Marchetti, AdrianTranscriptome statistics from samples obtained on LMG1411 collected on the Gould (LMG1411) in the Western Antarctica Peninsula in 2014. (Polar Transcriptomes project) For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/665311
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ArticleDifferent iron storage strategies among bloom-forming diatoms(National Academy of Sciences, 2018-12-11) Lampe, Robert H. ; Mann, Elizabeth L. ; Cohen, Natalie R. ; Till, Claire P. ; Thamatrakoln, Kimberlee ; Brzezinski, Mark A. ; Bruland, Kenneth W. ; Twining, Benjamin ; Marchetti, AdrianDiatoms are prominent eukaryotic phytoplankton despite being limited by the micronutrient iron in vast expanses of the ocean. As iron inputs are often sporadic, diatoms have evolved mechanisms such as the ability to store iron that enable them to bloom when iron is resupplied and then persist when low iron levels are reinstated. Two iron storage mechanisms have been previously described: the protein ferritin and vacuolar storage. To investigate the ecological role of these mechanisms among diatoms, iron addition and removal incubations were conducted using natural phytoplankton communities from varying iron environments. We show that among the predominant diatoms, Pseudo-nitzschia were favored by iron removal and displayed unique ferritin expression consistent with a long-term storage function. Meanwhile, Chaetoceros and Thalassiosira gene expression aligned with vacuolar storage mechanisms. Pseudo-nitzschia also showed exceptionally high iron storage under steady-state high and low iron conditions, as well as following iron resupply to iron-limited cells. We propose that bloom-forming diatoms use different iron storage mechanisms and that ferritin utilization may provide an advantage in areas of prolonged iron limitation with pulsed iron inputs. As iron distributions and availability change, this speculated ferritin-linked advantage may result in shifts in diatom community composition that can alter marine ecosystems and biogeochemical cycles.
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ArticleThe Marine Microbial Eukaryote Transcriptome Sequencing Project (MMETSP) : illuminating the functional diversity of eukaryotic life in the oceans through transcriptome sequencing(Public Library of Science, 2014-06-24) Keeling, Patrick J. ; Burki, Fabien ; Wilcox, Heather M. ; Allam, Bassem ; Allen, Eric E. ; Amaral-Zettler, Linda A. ; Armbrust, E. Virginia ; Archibald, John M. ; Bharti, Arvind K. ; Bell, Callum J. ; Beszteri, Bank ; Bidle, Kay D. ; Cameron, Connor T. ; Campbell, Lisa ; Caron, David A. ; Cattolico, Rose Ann ; Collier, Jackie L. ; Coyne, Kathryn J. ; Davy, Simon K. ; Deschamps, Phillipe ; Dyhrman, Sonya T. ; Edvardsen, Bente ; Gates, Ruth D. ; Gobler, Christopher J. ; Greenwood, Spencer J. ; Guida, Stephanie M. ; Jacobi, Jennifer L. ; Jakobsen, Kjetill S. ; James, Erick R. ; Jenkins, Bethany D. ; John, Uwe ; Johnson, Matthew D. ; Juhl, Andrew R. ; Kamp, Anja ; Katz, Laura A. ; Kiene, Ronald P. ; Kudryavtsev, Alexander N. ; Leander, Brian S. ; Lin, Senjie ; Lovejoy, Connie ; Lynn, Denis ; Marchetti, Adrian ; McManus, George ; Nedelcu, Aurora M. ; Menden-Deuer, Susanne ; Miceli, Cristina ; Mock, Thomas ; Montresor, Marina ; Moran, Mary Ann ; Murray, Shauna A. ; Nadathur, Govind ; Nagai, Satoshi ; Ngam, Peter B. ; Palenik, Brian ; Pawlowski, Jan ; Petroni, Giulio ; Piganeau, Gwenael ; Posewitz, Matthew C. ; Rengefors, Karin ; Romano, Giovanna ; Rumpho, Mary E. ; Rynearson, Tatiana A. ; Schilling, Kelly B. ; Schroeder, Declan C. ; Simpson, Alastair G. B. ; Slamovits, Claudio H. ; Smith, David R. ; Smith, G. Jason ; Smith, Sarah R. ; Sosik, Heidi M. ; Stief, Peter ; Theriot, Edward ; Twary, Scott N. ; Umale, Pooja E. ; Vaulot, Daniel ; Wawrik, Boris ; Wheeler, Glen L. ; Wilson, William H. ; Xu, Yan ; Zingone, Adriana ; Worden, Alexandra Z.Microbial ecology is plagued by problems of an abstract nature. Cell sizes are so small and population sizes so large that both are virtually incomprehensible. Niches are so far from our everyday experience as to make their very definition elusive. Organisms that may be abundant and critical to our survival are little understood, seldom described and/or cultured, and sometimes yet to be even seen. One way to confront these problems is to use data of an even more abstract nature: molecular sequence data. Massive environmental nucleic acid sequencing, such as metagenomics or metatranscriptomics, promises functional analysis of microbial communities as a whole, without prior knowledge of which organisms are in the environment or exactly how they are interacting. But sequence-based ecological studies nearly always use a comparative approach, and that requires relevant reference sequences, which are an extremely limited resource when it comes to microbial eukaryotes. In practice, this means sequence databases need to be populated with enormous quantities of data for which we have some certainties about the source. Most important is the taxonomic identity of the organism from which a sequence is derived and as much functional identification of the encoded proteins as possible. In an ideal world, such information would be available as a large set of complete, well-curated, and annotated genomes for all the major organisms from the environment in question. Reality substantially diverges from this ideal, but at least for bacterial molecular ecology, there is a database consisting of thousands of complete genomes from a wide range of taxa, supplemented by a phylogeny-driven approach to diversifying genomics. For eukaryotes, the number of available genomes is far, far fewer, and we have relied much more heavily on random growth of sequence databases, raising the question as to whether this is fit for purpose.
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Working PaperUS National BioGeoSCAPES Workshop Report(Woods Hole Oceangraphic Institution, 2023-01-09) Twining, Benjamin S. ; Saito, Mak A. ; Santoro, Alyson E. ; Marchetti, Adrian ; Levine, Naomi M.BioGeoSCAPES (BGS) is an international program being developed to understand controls on ocean productivity and metabolism by integrating systems biology (‘omics) and biogeochemistry (Figure 1). To ensure global input into the design of the BGS Program, countries interested in participating were tasked with holding an organizing meeting to discuss the country-specific research priorities. A United States BGS planning meeting, sponsored by the Ocean Carbon & Biogeochemistry (OCB) Project Office, was convened virtually November 10-12, 2021. The objectives of the meeting were to communicate the planning underway by international partners, engage the US community to explore possible national contributions to such a program, and build understanding, support, and momentum for US efforts towards BGS. The meeting was well-attended, with 154 participants and many fruitful discussions that are summarized in this document. Key outcomes from the meeting were the identification of additional programs and partners for BGS, a prioritization of measurements requiring intercalibration, and the development of a consensus around key considerations to be addressed in a science plan. Looking forward, the hope is that this workshop will serve as the foundation for future US and international discussions and planning for a BGS program, enabled by NSF funding for an AccelNet project (AccelNet - Implementation: Development of an International Network for the Study of Ocean Metabolism and Nutrient Cycles on a Changing Planet (BioGeoSCAPES)), beginning in 2022.
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DatasetBiovolume data from samples obtained on Gould cruise LMG1411 in the Western Antarctica Peninsula during 2014 (Polar Transcriptome project).(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-17) Marchetti, AdrianBiovolume data from samples obtained on Gould cruise LMG1411 in the Western Antarctica Peninsula during 2014 (Polar Transcriptome project). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/666234
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ArticleDecline in plankton diversity and carbon flux with reduced sea ice extent along the Western Antarctic Peninsula(Nature Research, 2021-08-16) Lin, Yajuan ; Moreno, Carly ; Marchetti, Adrian ; Ducklow, Hugh W. ; Schofield, Oscar M. E. ; Delage, Erwan ; Meredith, Michael M. ; Li, Zuchuan ; Eveillard, Damien ; Chaffron, Samuel ; Cassar, NicolasSince the middle of the past century, the Western Antarctic Peninsula has warmed rapidly with a significant loss of sea ice but the impacts on plankton biodiversity and carbon cycling remain an open question. Here, using a 5-year dataset of eukaryotic plankton DNA metabarcoding, we assess changes in biodiversity and net community production in this region. Our results show that sea-ice extent is a dominant factor influencing eukaryotic plankton community composition, biodiversity, and net community production. Species richness and evenness decline with an increase in sea surface temperature (SST). In regions with low SST and shallow mixed layers, the community was dominated by a diverse assemblage of diatoms and dinoflagellates. Conversely, less diverse plankton assemblages were observed in waters with higher SST and/or deep mixed layers when sea ice extent was lower. A genetic programming machine-learning model explained up to 80% of the net community production variability at the Western Antarctic Peninsula. Among the biological explanatory variables, the sea-ice environment associated plankton assemblage is the best predictor of net community production. We conclude that eukaryotic plankton diversity and carbon cycling at the Western Antarctic Peninsula are strongly linked to sea-ice conditions.
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DatasetBLASTp homology data from genes obtained in samples collected on the Gould (LMG1411) cruise in the Western Antarctica Peninsula during 2014 (Polar Transcriptomes project).(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-06-11) Marchetti, AdrianBLASTp homology data from genes obtained in samples collected on the Gould (LMG1411) cruise in the Western Antarctica Peninsula during 2014 (Polar Transcriptomes project). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/665454
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DatasetIsolate information on genes found in samples collected on the Gould (LMG1411) cruise in the Western Antarctica Peninsula in 2014 (Polar Transcriptomes project).(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2019-04-18) Marchetti, AdrianIsolate information on genes found in samples collected on the Gould (LMG1411) cruise in the Western Antarctica Peninsula in 2014 (Polar Transcriptomes project). For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/665288
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DatasetNCBI project accession and library information on each sample analyzed in upwelling experiments conducted on two phytoplankton species isolated from the California Upwelling Zone(Biological and Chemical Oceanography Data Management Office (BCO-DMO). Contact: bco-dmo-data@whoi.edu, 2021-03-17) Marchetti, AdrianTwo phytoplankton species, isolated from the California Upwelling Zone - Chaetoceros deicipiens (UNC1416) and Emiliania Huxleyi (UNC1419) - were cultured at 12 degrees Celsius in artificial Aquil* medium using trace metal clean (TMC) techniques. Upwelling conveyor belt cycle (UCBC) simulations were performed by transitioning the cultures to different nutrient and light regimes. RNA transcriptome libraries were created using the Illumina TruSeq Stranded mRNA Library Preparation Kit for C. dicipiens, and the KAPA stranded mRNA-Seq kit for Illumina platforms for E. huxleyi. Samples were sequenced on an Illumina MiSeq. This dataset includes the NCBI project accession and library information on each sample analyzed in the upwelling experiments. For a complete list of measurements, refer to the full dataset description in the supplemental file 'Dataset_description.pdf'. The most current version of this dataset is available at: https://www.bco-dmo.org/dataset/826494
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ArticleEvaluation of new and net community production estimates by multiple ship-based and autonomous observations in the Northeast Pacific Ocean(University of California Press, 2023-06-16) Niebergall, Alexandria K. ; Traylor, Shawnee ; Huang, Yibin ; Feen, Melanie ; Meyer, Meredith G. ; McNair, Heather M. ; Nicholson, David P. ; Fassbender, Andrea J. ; Omand, Melissa M. ; Marchetti, Adrian ; Menden-Deuer, Susanne ; Tang, Weiyi ; Gong, Weida ; Tortell, Philippe D. ; Hamme, Roberta C. ; Cassar, NicolasNew production (NP) and net community production (NCP) measurements are often used as estimates of carbon export potential from the mixed layer of the ocean, an important process in the regulation of global climate. Diverse methods can be used to measure NP and NCP, from research vessels, autonomous platforms, and remote sensing, each with its own set of benefits and uncertainties. The various methods are rarely applied simultaneously in a single location, limiting our ability for direct comparisons of the resulting measurements. In this study, we evaluated NP and NCP from thirteen independent datasets collected via in situ, in vitro, and satellite-based methods near Ocean Station Papa during the 2018 Northeast Pacific field campaign of the NASA project EXport Processes in the Ocean from RemoTe Sensing (EXPORTS). Altogether, the datasets indicate that carbon export potential was relatively low (median daily averages between −5.1 and 12.6 mmol C m−2 d−1), with most measurements indicating slight net autotrophy in the region. This result is consistent with NCP estimates based on satellite measurements of sea surface temperature and chlorophyll a. We explored possible causes of discrepancies among methods, including differences in assumptions about stoichiometry, vertical integration, total volume sampled, and the spatiotemporal extent considered. Results of a generalized additive mixed model indicate that the spatial variation across platforms can explain much of the difference among methods. Once spatial variation and temporal autocorrelation are considered, a variety of methods can provide consistent estimates of NP and NCP, leveraging the strengths of each approach.
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Working PaperEXPORTS Measurements and Protocols for the NE Pacific Campaign(NASA STI Program and Woods Hole Oceanographic Institution, 2021-02) Behrenfeld, Michael J. ; Benitez-Nelson, Claudia R. ; Boss, Emmanuel S. ; Brzezinski, Mark A. ; Buck, Kristen N. ; Buesseler, Ken O. ; Burd, Adrian B. ; Carlson, Craig A. ; Cassar, Nicolas ; Cetinić, Ivona ; Close, Hilary G. ; Craig, Susanne E. ; D'Asaro, Eric A. ; Durkin, Colleen A. ; Estapa, Margaret L. ; Fassbender, Andrea ; Fox, James ; Freeman, Scott ; Gifford, Scott M. ; Gong, Weida ; Graff, Jason R. ; Gray, Deric ; Guidi, Lionel ; Halsey, Kim ; Hansell, Dennis A. ; Haëntjens, Nils ; Horner, Tristan J. ; Jenkins, Bethany D. ; Jones, Janice L. ; Karp-Boss, Lee ; Kramer, Sasha J. ; Lam, Phoebe J. ; Lee, Craig M. ; Lee, Jong-Mi ; Liu, Shuting ; Mannino, Antonio ; Maas, Amy E. ; Marchal, Olivier ; Marchetti, Adrian ; McDonnell, Andrew M. P. ; McNair, Heather ; Menden-Deuer, Susanne ; Morison, Francoise ; Nelson, Norman B. ; Nicholson, David P. ; Niebergall, Alexandria K. ; Omand, Melissa M. ; Passow, Uta ; Perry, Mary J. ; Popp, Brian N. ; Proctor, Chris ; Rafter, Patrick ; Roca-Martí, Montserrat ; Roesler, Collin S. ; Rubin, Edwina ; Rynearson, Tatiana A. ; Santoro, Alyson E. ; Siegel, David A. ; Sosik, Heidi M. ; Soto Ramos, Inia ; Stamieszkin, Karen ; Steinberg, Deborah K. ; Stephens, Brandon M. ; Thompson, Andrew F. ; Van Mooy, Benjamin A. S. ; Zhang, XiaodongEXport Processes in the Ocean from Remote Sensing (EXPORTS) is a large-scale NASA-led and NSF co-funded field campaign that will provide critical information for quantifying the export and fate of upper ocean net primary production (NPP) using satellite information and state of the art technology.
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ArticleAn operational overview of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) Northeast Pacific field deployment(University of California Press, 2021-07-07) Siegel, David A. ; Cetinić, Ivona ; Graff, Jason R. ; Lee, Craig M. ; Nelson, Norman B. ; Perry, Mary J. ; Soto Ramos, Inia ; Steinberg, Deborah K. ; Buesseler, Ken O. ; Hamme, Roberta C. ; Fassbender, Andrea ; Nicholson, David P. ; Omand, Melissa M. ; Robert, Marie ; Thompson, Andrew F. ; Amaral, Vinicius ; Behrenfeld, Michael J. ; Benitez-Nelson, Claudia R. ; Bisson, Kelsey ; Boss, Emmanuel S. ; Boyd, Philip ; Brzezinski, Mark A. ; Buck, Kristen N. ; Burd, Adrian B. ; Burns, Shannon ; Caprara, Salvatore ; Carlson, Craig A. ; Cassar, Nicolas ; Close, Hilary G. ; D'Asaro, Eric A. ; Durkin, Colleen A. ; Erickson, Zachary K. ; Estapa, Margaret L. ; Fields, Erik ; Fox, James ; Freeman, Scott ; Gifford, Scott M. ; Gong, Weida ; Gray, Deric ; Guidi, Lionel ; Haëntjens, Nils ; Halsey, Kim ; Huot, Yannick ; Hansell, Dennis A. ; Jenkins, Bethany D. ; Karp-Boss, Lee ; Kramer, Sasha J. ; Lam, Phoebe J. ; Lee, Jong-Mi ; Maas, Amy E. ; Marchal, Olivier ; Marchetti, Adrian ; McDonnell, Andrew M. P. ; McNair, Heather ; Menden-Deuer, Susanne ; Morison, Francoise ; Niebergall, Alexandria K. ; Passow, Uta ; Popp, Brian N. ; Potvin, Geneviève ; Resplandy, Laure ; Roca-Martí, Montserrat ; Roesler, Collin S. ; Rynearson, Tatiana A. ; Traylor, Shawnee ; Santoro, Alyson E. ; Seraphin, Kanesa ; Sosik, Heidi M. ; Stamieszkin, Karen ; Stephens, Brandon M. ; Tang, Weiyi ; Van Mooy, Benjamin ; Xiong, Yuanheng ; Zhang, XiaodongThe goal of the EXport Processes in the Ocean from RemoTe Sensing (EXPORTS) field campaign is to develop a predictive understanding of the export, fate, and carbon cycle impacts of global ocean net primary production. To accomplish this goal, observations of export flux pathways, plankton community composition, food web processes, and optical, physical, and biogeochemical (BGC) properties are needed over a range of ecosystem states. Here we introduce the first EXPORTS field deployment to Ocean Station Papa in the Northeast Pacific Ocean during summer of 2018, providing context for other papers in this special collection. The experiment was conducted with two ships: a Process Ship, focused on ecological rates, BGC fluxes, temporal changes in food web, and BGC and optical properties, that followed an instrumented Lagrangian float; and a Survey Ship that sampled BGC and optical properties in spatial patterns around the Process Ship. An array of autonomous underwater assets provided measurements over a range of spatial and temporal scales, and partnering programs and remote sensing observations provided additional observational context. The oceanographic setting was typical of late-summer conditions at Ocean Station Papa: a shallow mixed layer, strong vertical and weak horizontal gradients in hydrographic properties, sluggish sub-inertial currents, elevated macronutrient concentrations and low phytoplankton abundances. Although nutrient concentrations were consistent with previous observations, mixed layer chlorophyll was lower than typically observed, resulting in a deeper euphotic zone. Analyses of surface layer temperature and salinity found three distinct surface water types, allowing for diagnosis of whether observed changes were spatial or temporal. The 2018 EXPORTS field deployment is among the most comprehensive biological pump studies ever conducted. A second deployment to the North Atlantic Ocean occurred in spring 2021, which will be followed by focused work on data synthesis and modeling using the entire EXPORTS data set.
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ArticleThe dawn of the BioGeoSCAPES Program: ocean metabolism and nutrient cycles on a changing planet(Oceanography Society, 2024-05-23) Saito, Mak A. ; Alexander, Harriet ; Benway, Heather M. ; Boyd, Philip W. ; Gledhill, Martha ; Kujawinski, Elizabeth B. ; Levine, Naomi M. ; Maheigan, Mai ; Marchetti, Adrian ; Obernosterer, Ingrid ; Santoro, Alyson E. ; Shi, Dalin ; Suzuki, Koji ; Tagliabue, Alessandro ; Twining, Benjamin S. ; Maldonado, Maria T.Biogeochemical cycles constitute Earth’s life support system and distinguish our planet from others in this solar system. Microorganisms are the primary drivers of these cycles. Understanding the controls on marine microbial dynamics and how microbes will respond to environmental change is essential for building and assessing model-based forecasts and generating robust projections of climate change impacts on ocean productivity and biogeochemical cycles. An international community effort has been underway to create a global-scale marine microbial biogeochemistry research program to tackle gaps in this understanding. The BioGeoSCAPES: Ocean Metabolism and Nutrient Cycles on a Changing Planet program will identify and quantify how marine microbes adjust to a changing climate and assess the consequences for global biogeochemical cycles. This article summarizes the ongoing efforts to launch BioGeoSCAPES.