Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A large, living Pleurosira laevis cell has many disc shaped chloroplasts.
Sarah A. Spaulding, PhD
(She/they)Sarah is an aquatic ecologist, with a focus of expertise in algae, including diatoms and harmful algae.
Sarah's research interests cover the application of taxonomy, paleoecology, and biogeography to environmental assessment. Most recently, Sarah worked on regional river surveys, using diatoms, eDNA, and algal metrics to assess the impacts of a variety of stresses on freshwater organisms. For several years, Sarah has managed the USGS BioData Algal Taxonomy section, keeping algal nomenclature up to date and in accordance with the International Code of Algae, Fungi, and Plants (INA). She is passionate about sharing algal taxonomy and ecology with scientists, students, and the public. Sarah currently serves as the Chair of the Editorial Review Board for the collaborative (USGS, EPA & University of Colorado), electronic, peer-reviewed flora, Diatoms of North America (diatoms.org).
Sarah's published research covers a wide range of topics including atmospheric deposition of nitrogen, aquatic invasive species, environmental DNA sequencing, harmful algal blooms, paleolimnology, automated identification of organisms, development of new assessment methods, and modeling algal species response.
Affiliations and Memberships*
Society for Freshwater Science, member (2016-), Taxonomic Certification Committee (2018-)
International Society of Diatom Research, President (2023-),Vice President (2021-2023), Member Advisory Council (2008, 2016, 2018-2020), Associate Editor (2013, 2016, 2017), Chair of Web Working Group
Phycological Society of America (2010-)
American Association for the Advancement of Science (2015-2017, 2019-)
Association for the Sciences of Limnology and Oceanography (2019-)
Honors and Awards
Elizabeth Jester Fellows Award, National Water Monitoring Council (2023)
US Geological Survey Achievement Award (2007-2016, 2019-2020)
EPA Ecosystems Protection Program, Region 8, Greater Kudu Nomination (2007)
US Geological Survey STAR Award for Outstanding Technical Assistance and Outreach (2006)
Science and Products
Paleoecological data from sediment collected in 2020 from Santa Fe Lake, New Mexico
This dataset contains carbon and nitrogen stable isotope values, percent carbon and percent nitrogen, algal pigment data, and diatom taxonomy from lake sediment layers dating back to 1749 Common Era (CE) for Santa Fe lake, New Mexico. Subalpine and alpine lakes are typically sensitive indicators of anthropogenically driven global change. Lake sediment records in the western United States have docu
A national harmonized dataset of discrete chlorophyll from lakes and streams (2005-2022)
This data release contains a 17-year record (2005-2022) of discrete chlorophyll data from inland waters, collected from across the nation and territories. These data are from discrete samples (collected in the field and analyzed in the laboratory) from plankton (suspended algae) and periphyton (benthic algae) from lakes, streams, rivers, reservoirs, canals, and other sites. These data are gathered
Paleoecological data from The Loch and Sky Pond, Rocky Mountain National Park
Diatom taxonomy, carbon and nitrogen stable isotope values, and algal pigment data from lake sediment layers dating back to 1600 Common Era (CE) for Sky Pond and The Loch in Rocky Mountain National Park.
Diatoms
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A large, living Pleurosira laevis cell has many disc shaped chloroplasts.
Diatoms
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A scanning electron micrograph (SEM) shows one valve of an unusual species within the genus Aneumastus.
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A scanning electron micrograph (SEM) shows one valve of an unusual species within the genus Aneumastus.
Filter Total Items: 37
Climatic variability as a principal driver of primary production in the southernmost subalpine Rocky Mountain lake
Mountain lakes are sensitive indicators of anthropogenically driven global change, with lake sediment records documenting increased primary production during the twentieth century. Atmospheric nutrient deposition and warming have been attributed to changes in other Western mountain lakes, however, the intensity of these drivers varies. We analyzed a sediment core representing a 270-year record fro
Authors
Anna Shampain, Jill Baron, Peter R. Leavitt, Sarah Spaulding
Integrated water resources trend assessments: State of the science, challenges, and opportunities for advancement
Water is vital to human life and healthy ecosystems. Here we outline the current state of national-scale water resources trend assessments, identify key gaps, and suggest advancements to better address critical issues related to changes in water resources that may threaten human development or the environment. Questions like, “Do we have less suitable drinking water now than we had 20 years ago?”
Authors
Sarah M. Stackpoole, Gretchen P. Oelsner, Edward G. Stets, Jory Seth Hecht, Zachary Johnson, Anthony J. Tesoriero, Michelle A. Walvoord, Jeffrey G. Chanat, Krista A. Dunne, Phillip J. Goodling, Bruce D. Lindsey, Michael Meador, Sarah Spaulding
Natural and anthropogenic influences on benthic cyanobacteria in streams of the northeastern United States
Benthic cyanobacteria are widespread in streams and rivers and have the potential to release toxins. In large numbers, these microorganisms and their toxins present a risk to human health. Cyanobacterial abundance in stream biofilms is typically related to single or a limited set of environmental factors, mainly light availability, water temperature, and nutrient concentrations. However, these fac
Authors
Nicholas O. Schulte, Daren M. Carlisle, Sarah Spaulding
A web-based tool for assessing the condition of benthic diatom assemblages in streams and rivers of the conterminous United States
Benthic diatom assemblages are known to be indicative of water quality but have yet to be widely adopted in biological assessments in the United States due to several limitations. Our goal was to address some of these limitations by developing regional multi-metric indices (MMIs) that are robust to inter-laboratory taxonomic inconsistency, adjusted for natural covariates, and sensitive to a wide r
Authors
Daren Carlisle, Sarah Spaulding, Meredith Tyree, Nicholas O. Schulte, Sylvia S Lee, Richard M. Mitchell, Amina A. Pollard
Perspectives on the paleolimnology of the late Eocene Florissant lake from diatom and sedimentary evidence at Clare’s Quarry, Teller County, Colorado, USA
The late Eocene Florissant Formation in central Colorado is a rich and diverse continental Lagerstätte yielding well-preserved fossil assemblages from lacustrine and fluvial facies. This investigation focused on the lacustrine facies at Clare’s Quarry and used biotic and abiotic evidence to characterize aspects of the lake and processes that resulted in the accumulation and preservation of the hos
Authors
Mary Ellen Benson, Dena M. Smith, Sarah A. Spaulding
Diatoms.org: Supporting taxonomists, connecting communities
Consistent identification of diatoms is a prerequisite for studying their ecology, biogeography, and successful application as environmental indicators. However, taxonomic consistency among observers has been difficult to achieve because taxonomic information is scattered across numerous literature sources, presenting challenges to the diatomist. Firstly, literature is often inaccessible because o
Authors
Sarah Spaulding, Marina Potapova, Ian W. Bishop, Sylvia S. Lee, Tim Gasperak, Elena Jovanoska, Paula C. Furey, Mark B. Edlund
Nutrients and warming interact to force mountain lakes into unprecedented ecological state
While deposition of reactive nitrogen (N) in the 20th century has been strongly linked to changes in diatom assemblages in high-elevation lakes, pronounced and contemporaneous changes in other algal groups suggest additional drivers. We explored the origin and magnitude of changes in two mountain lakes from the end of the Little Ice Age at ca. 1850, to ca. 2010, using lake sediments. We found dram
Authors
Isabella A. Oleksy, Jill S. Baron, Peter Leavitt, Sarah Spaulding
Characterizing benthic macroinvertebrate and algal biological condition gradient models for California wadeable Streams, USA
The Biological Condition Gradient (BCG) is a conceptual model that describes changes in aquatic communities under increasing levels of anthropogenic stress. The BCG helps decision-makers connect narrative water quality goals (e.g., maintenance of natural structure and function) to quantitative measures of ecological condition by linking index thresholds based on statistical distributions (e.g., pe
Authors
Michael J. Paul, Ben Jessup, Larry R. Brown, James Carter, Marco Cantonati, Donald F. Charles, Jeroen Gerritsen, Dave Herbst, Rosalina Stancheva, Jeanette K. Howard, Bill Isham, Rex Lowe, Raphael D Mazor, Patina K. Mendez, Peter R Ode, Alison O'Dowd, Yangdong Pan, Andrew C. Rehn, Sarah A. Spaulding, Martha Sutula, Susanna Theroux
Reduction of taxonomic bias in diatom species data
Inconsistency in taxonomic identification and analyst bias impede the effective use of diatom data in regional and national stream and lake surveys. In this study, we evaluated the effect of existing protocols and a revised protocol on the precision of diatom species counts. The revised protocol adjusts four elements of sample preparation, taxon identification and enumeration, and quality control
Authors
Meredith Tyree, Ian W. Bishop, Charles P. Hawkins, Richard M. Mitchell, Sarah A. Spaulding
Diatom enumeration method influences biological assessments of southeastern USA streams
Current fixed-count enumeration methods for benthic diatoms are likely inadequate for most research and monitoring objectives. These methods underestimate taxa richness and may fail to detect losses of species caused by human impacts. Consequently, the full potential of diatoms is not realized in current assessments of biological integrity or species diversity. In this study, we hypothesize that a
Authors
Meredith Tyree, Daren M. Carlisle, Sarah Spaulding
Taxonomic harmonization may reveal a stronger association between diatom assemblages and total phosphorus in large datasets
Diatom data have been collected in large-scale biological assessments in the United States, such as the U.S. Environmental Protection Agency’s National Rivers and Streams Assessment (NRSA). However, the effectiveness of diatoms as indicators may suffer if inconsistent taxon identifications across different analysts obscure the relationships between assemblage composition and environmental variable
Authors
Sylvia S Lee, Ian W. Bishop, Sarah A. Spaulding, Richard M. Mitchell, Lester Yuan
A diatom voucher flora from selected southeast rivers (USA)
This flora is intended to serve as an image voucher for samples analyzed for the U.S. Geological Survey Southeast Stream Quality Assessment (SESQA). The SESQA study included measurement of watershed and water quality parameters to determine the factors that have the greatest potential to alter biotic condition. Algal samples were collected at 108 sites in 2014, from streams representing gradients
Authors
Ian W. Bishop, Rhea R.M. Esposito, Meredith Tyree, Sarah A. Spaulding
Non-USGS Publications**
Enache, M., Potapova, M.G., Tyree, M.A. and Spaulding, S.A. 2022. Aulacoseira novacaesarea sp. nov. (Bacillariophyta) a new centric diatom species from the northeastern United States. Diatom Research doi: 10.1080/0269249X.2022.2118834
Potapova, M.G., Lee, S.S., Spaulding, S.A. and Schulte, N.O. 2022. A harmonized dataset of sediment diatoms from hundreds of lakes in the northeast United States. Scientific Data-Nature 9:540 doi: 10.1038/s41597-022-01661-3
Li, D., Record, S., Sokol, E., Bitters, M.E., Chen, M.Y., Chung, Y.A., Helmus, M. Jaimes, R., Jansen, L., Jarzyna, M.A., Just, M.G., LaMontagne, J.M., Melbourne, B., Moss, W., Norman, K., Parker, S., Robinson, N., Seyednasrollah, B., Smith, C., Spaulding, S., Surasinghe, T., Thomsen, S., Zarnetske, P. 2022. Tidy NEON organismal data for biodiversity research. Ecosphere.
Nagy et al. 2021. Harnessing the NEON data revolution to advance open environmental science with a diverse and data-capable community. Ecosphere. doi: 10.1002/ecs2.3833
Hamsher, S.E., Kociolek, J.P., Spaulding, S.A. and Saleh, A.I. 2021. Taxonomy and nomenclature of members within the Obtusae section of Nitzschia Hassall (Bacillariophyceae) including descriptions of two new species. Fottea 2: 247-258. doi: 10.5507/fot.2021.010
Williams, D.M., Spaulding, S.A. and Bishop, I.W. 2021. Studies on type material from Kützing's diatom collection IV: The basionym, author and type of Tetracyclus rupestre. Phytotaxa. doi: 10.11646/phytotaxa.498.1.5
Benson, M.A., Smith, D.M. and Spaulding, S.A. 2021. Perspectives on the paleolimnology of the late Eocene Florissant lake from diatom and sedimentary records at Clare's Quarry, Teller County, Colorado, USA. Geological Society of America Proceedings. in Starratt, S.W. and Rosen, M.R., eds., From Saline to Freshwater: The Diversity of Western Lakes in Space and Time: Geological Society of America Special Paper 536.
Paul, M.J., Jessup, B., Brown, L., Carter, J., Cantonati, M., Charles, D.F., Gerritsen, J., Herbst, D., Hristova, R.S., Howard, J., Isham, B., Lowe, R., Mazor, R., Mendez, P., Ode, P., O'Dowd, A., Olson, J., Pan, Y., Rehn, A., Spaulding, S.A., Sutula, M. and Theroux, S. 2020. Characterizing benthic macroinvertebrate and algal biological condition gradient models for California wadeable streams, USA. Ecological Indicators 177: 106618. doi: 10.1016/j.ecolind.2020.106618
Meilijson, A., Hilgen, F., Sepúlveda, J., Steinberg, J., Flecker, R., Waldmann, N.D., Spaulding, S.A., Bialik, O.M., Ilner, P., Boudinot, F.G. and Makovsky, Y. 2019. Integrated stratigraphy of Messinian evaporites in the deep Eastern Mediterranean reveal long lasting halite deposition through Atlantic connectivity. Earth Science Reviews 194: 374-398
Lee, S.S., Bishop, I.W., Spaulding, S.A., Mitchell, R. and Yuan, L.L. 2019. Harmonization and revision of a national diatom dataset for use in the development of water quality indicators. Ecological Indicators 102:166-174.
Moser, J., Baron, J., Brahney, J., Olesky, I., Saros, J., Hundey, S., Sadro, S., Kopacek, Sommaruga, Kainze, Strecker, A., Chandra, D., Walters, D., Preston, Michelutti, N., Lepori, Spaulding, S., Hik, Christianson, Melack, J. and Smol, J. 2019. Mountain lakes: eyes on global environmental change. Global and Planetary Change 178: 77-95.
Bishop, I.W., Tucker, S.T., Joeckel, R.M. and Spaulding, S.A. 2018. Rare and diverse benthic fossil diatoms from the upper Ogallala Group (late Miocene) near Scotia, NE (USA) Nova Hedwigia, Beihefte 147: 261-294.
Bishop, I. and Spaulding, S.A. 2017. Seasonal population dynamics and size restoration in Didymosphenia geminata. Journal of Phycology 53: 652-663.
Spaulding, S.A. 2016. An uncertain synergy between atmospheric deposition and warming: high-elevation lakes of Grand Teton National Park. Mountain Views, Chronicles of the Consortium for Integrated Climate Research in Western Mountains 10(1)
Sakaeva, A., Stanish, L.F., Kohler, T.J., Spaulding, S.A., McKnight, D.M., Howkins, A., Welch, K.A., Lyons, W.B., Sokol, E.R. and Barrett, J.E. 2016. Evidence for dispersal and habitat controls on pond diatom communities in the McMurdo Sound Region of Antarctica. Polar Biology 1-16.
Bishop, I. and Spaulding, S.A. 2015. Tetracyclus hinziae (Bacillariophyta), a new species from the central Cascade Mountains (WA, USA). Phytotaxa 205(3). doi: 10.11646/phytotaxa.205.3.7
Bergey, E.A. and Spaulding. S.A. 2015. Didymosphenia: it’s more complicated. A response to the Forum article by Taylor and Bothwell (2014). Bioscience doi:10.1093/biosci/biu226
Cullis, J.D.S., McKnight, D.M. and Spaulding, S.A. 2015. Hydrodynamic control of benthic mats of Didymosphenia geminata at the reach scale. Canadian Journal of Fisheries and Aquatic Sciences 72(6): 902-914.
Personius, S.F., Briggs, R.W., Nelson, A.R., Schermer, E.R., Maharrey, J.Z., Sherrod, B.L., Spaulding, S.A. and Bradley, L. 2014. Holocene earthquakes and right-lateral slip on the left-lateral Darrington–Devils Mountain fault zone, northern Puget Sound, Washington. Geosphere doi: 10.1130/GES01067.1
Brahney, J., Spaulding, S, Ballantyne, A.P., Otu, M., Neff, J.C. 2014. Separating the influences of diagenesis, productivity, and anthropogenic nitrogen deposition on sedimentary d15N variations. Organic Geochemistry 75: 140-150.
Kociolek, J.P., Spaulding, S.A. and Lowe, R. 2015. Symmetrical Naviculoid Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Second Edition. Academic Press.
Brahney, J., Ballantyne, A., Kociolek, J.P., Spaulding, S.A., Otu, M., Porwall, T. and Neff, J.C. 2014. Dust mediated transfer of phosphorus to alpine lake ecosystems of the Wind River Range, Wyoming, USA. Biogeochemistry 120: 259-278.
Nakov, T., Ruck, E.C., Galachyants, Y., Spaulding, S.A. and Theriot, E. 2014. Molecular phylogeny of the Cymbellales (Heterokonthophyta: Bacillariophyceae) with a comparison of models for accommodating rate-variation across sites. Phycologia 53 (4): 359–373.
Benson, M.E., Kociolek, J.P., Spaulding, S.A., and Smith, D.M. 2012. Pre-Neogene (>23.8 MA) biochronology of non-marine diatoms, with an account of the late Eocene flora of the Florissant Formation, central Colorado, USA. Stratigraphy 9: 131-152.
Spaulding, S.A., Jewson, D., Bixby, R., Nelson, H. and McKnight, D.M. 2012. Automated measurement of diatom size. Limnology and Oceanography: Methods 10: 882-890.
Reid, B.L., Hernandez, K.L., Frangopoulis, M., Bauer, G., Lorca, M., Kilroy, C. and Spaulding, S.A. 2012. The invasion of the freshwater diatom Didymosphenia geminata in Patagonia: prospects, strategies, and implications for biosecurity of invasive species in continental waters. Conservation Letters doi: 10.1111/j.1755-263X.2012.00264.
Stanish, L.F., O’Neill, S.P., Gonzalez-Peña, A., Legg, T.M., Knelman, J., McKnight, D.M., Spaulding, S. and Nemergut, D.R. 2012. Bacterial-diatom community and co-occurrence relationships exist in microbial mats from polar desert streams. Environmental Microbiology doi: 10.1111/j.1462-2920.2012.02872.x.
Sundareshwar, P.V., Upadhayay, S., Abessa, M., Honomichl, S., Berdanier, B., Spaulding, S.A., Sandvik, C. and Trennepohl, A. 2011. Didymosphenia geminata: algal blooms in oligotrophic streams and rivers. Geophysical Research Letters 38: L10405, doi:10.1029/2010GL046599.
Spaulding, S.A., McKnight, D.M., Stanish, L., Van de Vijver, B. and Hodgson, D. 2010. Diatoms as indicators of environmental change in Antarctic and Sub-Antarctic freshwaters. In: Smol, J. and E.F. Stoermer (eds). The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, Cambridge pp. 267-286.
Spaulding, S.A., Kilroy, C. and Edlund, M. 2010. Diatoms as invasive species. In: Smol, J. and E.F. Stoermer (eds). The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, Cambridge pp. 560-569.
Rushforth, S.J., Edlund, M.B., Spaulding, S.A. and Stoermer, E.F. 2010. The Reimer Diatom Herbarium: an important resource for teaching and research. Proceedings of the Academy of Natural Sciences of Philadelphia.
Spaulding, S.A., Pool, J.R., Castro, S.I. and Hinz. 2010. Notes on species within the genus Encyonema Kützing, including two new species Encyonema reimeri sp. nov. and E. nickcafei sp. nov. and E. stoermeri nom. nov., stat. nov. Proceedings of the Academy of Natural Sciences of Philadelphia.
Morales, E.A., Edlund, M.B. and Spaulding, S.A. 2010. Description and ultrastructure of fragilarioid diatom species (Bacillariophyceae) morphologically similar to Pseudostaurosira elliptica (Schumann) Edlund et al. Phycological Research 58: 97-107.
Van de Vijver, B., Mataloni, G., Stanish L. and Spaulding, S.A. 2010. New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic Region and South Africa. Phycologia 49: 22-41.
Pite, D., Lane, K., Hermann, A, Spaulding, S.A. and Finney, B. 2009. Historical abundance and morphology of Didymosphenia geminata in Naknek Lake, Alaska. Acta Bot. Croat. 68: 183-197.
Kumar, S., Spaulding, S.A., Stohlgren, T., Hermann, K., Schmidt, T. and Bahls, L. 2009. Modelling the bioclimatic profile of the diatom Didymosphenia geminata. Frontiers in Ecology and the Environment. 8: 415-420.
Esposito, R.M.M., Spaulding, S.A., McKnight, D.M. , Lubinski, D. , Hall, B. , and Whittaker, T. 2008. Inland diatoms from the McMurdo Dry Valleys, Antarctica. Botany 86: 1378-1392.
Whittaker, T.E, Hall, B.L., Hendy, C.H. and Spaulding, S.A. 2008. Holocene surface-level changes and depositional environments at Lake Fryxell, Antarctica. The Holocene 18(5): 775-786.
Bothwell, M.L. and Spaulding, S.A. 2008. Synopsis: the 2007 International workshop on Didymosphenia geminata. Canadian Technical Report of Fisheries and Aquatic Sciences 2795.
Spaulding, S.A., Hermann, K.A. and Johnson, T. 2008. Confirmed distribution of Didymosphenia geminata (Lyngbye) Schmidt in North America. Proceedings, 2007 International Workshop on Didymosphenia geminata, Canadian Technical Report of Fisheries and Aquatic Sciences 2795.
Esposito, R. M. M., S. L. Horn, D. M. McKnight, M. J. Cox, M. C. Grant, S. A. Spaulding, P. T. Doran, and K. D. Cozzetto 2006. Antarctic climate cooling and response of diatoms in glacial meltwater streams, Geophys. Res. Lett., 33.
Edlund, M.B., E.A. Morales and S.A. Spaulding. 2006. The type and taxonomy of Fragilaria elliptica Schumann, a widely misconstrued taxon. Proceedings of the International Society of Diatom Research.
Edlund, M.B. and S.A. Spaulding. 2006. Restoration of maximum cell size by uniparental auxosporulation in Scoliopleura Grunow and Muelleria (Frenguelli) Frenguelli. In: Ognjanova-Rumenova and Manoylov (eds.), Fossil and Recent Phycological Studies, pp. 211-223
Kociolek, J.P., S.A. Spaulding, K. Sabbe, and W. Vyverman. 2004. New Gomphonema (Bacillariophyta) species from Tasmania. Phycologia 43:427-444.
Spaulding, S.A., A. Akbulut and J.P. Kociolek 2003. A new species of Aneumastus Mann and Stickle from Central Turkey. Diatom Research 18:149-160.
Kociolek, J.P. and S.A. Spaulding. 2002. Evolutionary relationships, species concepts and implications of two disparate freshwater, fossil centric diatoms (Bacillariophyta) from western North America. Journal of Phycology 38: 821-833.
Kociolek, J.P. and S.A. Spaulding. 2002. Symmetrical Naviculoid Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Academic Press. pp. 637-651.
Kociolek, J.P. and S.A. Spaulding. 2002. Eunotiod and Asymmetrical Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Academic Press. pp. 655-666.
Spaulding, S.A. and J.P. Kociolek. 2003. Freshwater diatoms (Bacillariophyceae) In: Goodman, S. and Benstead, J. (eds). Natural History of Madagascar, University of Chicago Press.
Spaulding, S.A., J.P. Kociolek and D. Davis. 2002. A new diatom genus from a playa lake in New Mexico, USA with the description of two new species. European Journal of Phycology 37: 135-143.
Stoermer, E.F, M. Julius, J.P. Kociolek and S.A. Spaulding. 2002. Centric Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Academic Press. pp. 559-562.
Strelnikova, N.I., E. Fourtanier, J.A. Barron, J.P. Kociolek, A. Mahood and S.A. Spaulding (2002). A species of the genus Coscinodiscus Ehrenberg from the Eocene of California. Proceedings of the 15th International Diatom Symposium, Ganter Verlag, Liechtenstein. pp. 359-380.
Kociolek, J.P., D. Lyon and S. Spaulding 2001. Revision of the South American species of Actinella In: Jahn, R., Kociolek, J.P., Witkowski , A. and Compère P. (eds). Lange-Bertalot-Festschrift: Studies on Diatoms, Koeltz Scientific Books, Koenigstein. pp. 131-166.
Kociolek, J.P. and S.A. Spaulding. 1999. Freshwater diatom biogeography. Nova Hedwigia 71: 223-241.
Spaulding, S.A., J.P. Kociolek and D. Wong. 1999. A taxonomic and systematic revision of the genus Muelleria (Bacillariophyta). Phycologia 38: 314-341.
Spaulding, S.A. and J.P. Kociolek. 1998. New Gomphonema species from Madagascar. Proceedings of the California Academy of Sciences 50: 361-379.
Spaulding, S.A. and J.P. Kociolek. 1998. The diatom genus Orthoseira: Ultrastructure and morphological variation in two species from Madagascar with comments on nomenclature in the genus. Diatom Research 13: 133-147.
Kociolek, J.P., S.A. Spaulding and J.C. Kingston. 1998. Valve morphology and systematic position of Navicula walkeri Sovereign, a diatom endemic to Oregon and California (USA) freshwaters. Nova Hedwigia.
Spaulding, S.A. and D. McKnight. 1998. Diatoms as Indicators of Environmental Change in Antarctic Freshwaters. In: Smol, J. and E.F. Stoermer (eds). The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, Cambridge. pp. 249-263.
McKnight, D.M., A. Alger, C.M. Tate, G. Shupe and S.A. Spaulding. 1997. Longitudinal patterns in algal abundance and species distribution in meltwater streams in Taylor Valley, Southern Victorialand, Antarctica. In: Priscu, J. (ed.). American Geophysical Union, Antarctic Research Series.
Fountain, A. and S.A. Spaulding. 1997. Researchers pool knowledge about Antarctic Dry Valleys. EOS, Transactions, American Geophysical Union 78: 295-298.
Spaulding, S.A. and E.F. Stoermer. 1997. Taxonomy and distribution of the genus Muelleria Frenguelli. Diatom Research 12: 95-113.
Spaulding, S.A., D. McKnight, E.F. Stoermer and P.T. Doran. 1997. Sedimentary record of diatoms in Lake Hoare, Antarctica. Journal of Paleolimnology 17: 403-420.
Laybourn-Parry, J., M. James, D. McKnight, J. Priscu, S.A. Spaulding and R.Shiel. 1997. The microbial plankton of Lake Fryxell, southern Victoria Land, Antarctica during the summers of 1992 and 1994. Polar Biology 17: 54-61.
Spaulding, S.A. 1996. Algal investigations at varying temporal scales in an extreme environment: McMurdo Dry Valleys lakes, Antarctica. Ph. D. Thesis, Colorado State University.
McKnight, D.M., E.D. Andrews, S.A. Spaulding and G.R. Aiken. 1994. Aquatic fulvic acids in eutrophic coastal ponds in Antarctica and comparison with other aquatic fulvic acids. Limnology and Oceanography 39:1972-1979.
Spaulding, S.A., D.M. McKnight and R.L. Smith. 1994. Temporal dynamics of phytoplankton populations in perennially ice-covered Lake Fryxell. Journal of Plankton Research 16: 527-541.
Spaulding, S.A, J.V. Ward and J. Baron. 1993. Winter phytoplankton dynamics in a subalpine lake. Archiv für Hydrobiology 129: 179-198.
Spaulding, S.A., M.A. Harris, D.M. McKnight and B.D. Rosenlund. 1991. Aquatic Biota. In: J. Baron, Biogeochemisty of Loch Vale Watershed. Springer-Verlag, New York.
McKnight, D., R.L. Smith, J.P. Bradbury, J. Baron and S.A. Spaulding. 1990. Phytoplankton dynamics in three Rocky Mountain lakes. Arctic and Alpine Research 22: 264-274.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
Science and Products
Paleoecological data from sediment collected in 2020 from Santa Fe Lake, New Mexico
This dataset contains carbon and nitrogen stable isotope values, percent carbon and percent nitrogen, algal pigment data, and diatom taxonomy from lake sediment layers dating back to 1749 Common Era (CE) for Santa Fe lake, New Mexico. Subalpine and alpine lakes are typically sensitive indicators of anthropogenically driven global change. Lake sediment records in the western United States have docu
A national harmonized dataset of discrete chlorophyll from lakes and streams (2005-2022)
This data release contains a 17-year record (2005-2022) of discrete chlorophyll data from inland waters, collected from across the nation and territories. These data are from discrete samples (collected in the field and analyzed in the laboratory) from plankton (suspended algae) and periphyton (benthic algae) from lakes, streams, rivers, reservoirs, canals, and other sites. These data are gathered
Paleoecological data from The Loch and Sky Pond, Rocky Mountain National Park
Diatom taxonomy, carbon and nitrogen stable isotope values, and algal pigment data from lake sediment layers dating back to 1600 Common Era (CE) for Sky Pond and The Loch in Rocky Mountain National Park.
Diatoms
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A large, living Pleurosira laevis cell has many disc shaped chloroplasts.
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A large, living Pleurosira laevis cell has many disc shaped chloroplasts.
Diatoms
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A scanning electron micrograph (SEM) shows one valve of an unusual species within the genus Aneumastus.
Diatoms are algae that reflect the biotic condition of streams, lakes and estuaries. Diatoms are important indicator organisms because they are sensitive to natural and human impacts, and monitoring their condition provides information about ecosystem health. A scanning electron micrograph (SEM) shows one valve of an unusual species within the genus Aneumastus.
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Climatic variability as a principal driver of primary production in the southernmost subalpine Rocky Mountain lake
Mountain lakes are sensitive indicators of anthropogenically driven global change, with lake sediment records documenting increased primary production during the twentieth century. Atmospheric nutrient deposition and warming have been attributed to changes in other Western mountain lakes, however, the intensity of these drivers varies. We analyzed a sediment core representing a 270-year record fro
Authors
Anna Shampain, Jill Baron, Peter R. Leavitt, Sarah Spaulding
Integrated water resources trend assessments: State of the science, challenges, and opportunities for advancement
Water is vital to human life and healthy ecosystems. Here we outline the current state of national-scale water resources trend assessments, identify key gaps, and suggest advancements to better address critical issues related to changes in water resources that may threaten human development or the environment. Questions like, “Do we have less suitable drinking water now than we had 20 years ago?”
Authors
Sarah M. Stackpoole, Gretchen P. Oelsner, Edward G. Stets, Jory Seth Hecht, Zachary Johnson, Anthony J. Tesoriero, Michelle A. Walvoord, Jeffrey G. Chanat, Krista A. Dunne, Phillip J. Goodling, Bruce D. Lindsey, Michael Meador, Sarah Spaulding
Natural and anthropogenic influences on benthic cyanobacteria in streams of the northeastern United States
Benthic cyanobacteria are widespread in streams and rivers and have the potential to release toxins. In large numbers, these microorganisms and their toxins present a risk to human health. Cyanobacterial abundance in stream biofilms is typically related to single or a limited set of environmental factors, mainly light availability, water temperature, and nutrient concentrations. However, these fac
Authors
Nicholas O. Schulte, Daren M. Carlisle, Sarah Spaulding
A web-based tool for assessing the condition of benthic diatom assemblages in streams and rivers of the conterminous United States
Benthic diatom assemblages are known to be indicative of water quality but have yet to be widely adopted in biological assessments in the United States due to several limitations. Our goal was to address some of these limitations by developing regional multi-metric indices (MMIs) that are robust to inter-laboratory taxonomic inconsistency, adjusted for natural covariates, and sensitive to a wide r
Authors
Daren Carlisle, Sarah Spaulding, Meredith Tyree, Nicholas O. Schulte, Sylvia S Lee, Richard M. Mitchell, Amina A. Pollard
Perspectives on the paleolimnology of the late Eocene Florissant lake from diatom and sedimentary evidence at Clare’s Quarry, Teller County, Colorado, USA
The late Eocene Florissant Formation in central Colorado is a rich and diverse continental Lagerstätte yielding well-preserved fossil assemblages from lacustrine and fluvial facies. This investigation focused on the lacustrine facies at Clare’s Quarry and used biotic and abiotic evidence to characterize aspects of the lake and processes that resulted in the accumulation and preservation of the hos
Authors
Mary Ellen Benson, Dena M. Smith, Sarah A. Spaulding
Diatoms.org: Supporting taxonomists, connecting communities
Consistent identification of diatoms is a prerequisite for studying their ecology, biogeography, and successful application as environmental indicators. However, taxonomic consistency among observers has been difficult to achieve because taxonomic information is scattered across numerous literature sources, presenting challenges to the diatomist. Firstly, literature is often inaccessible because o
Authors
Sarah Spaulding, Marina Potapova, Ian W. Bishop, Sylvia S. Lee, Tim Gasperak, Elena Jovanoska, Paula C. Furey, Mark B. Edlund
Nutrients and warming interact to force mountain lakes into unprecedented ecological state
While deposition of reactive nitrogen (N) in the 20th century has been strongly linked to changes in diatom assemblages in high-elevation lakes, pronounced and contemporaneous changes in other algal groups suggest additional drivers. We explored the origin and magnitude of changes in two mountain lakes from the end of the Little Ice Age at ca. 1850, to ca. 2010, using lake sediments. We found dram
Authors
Isabella A. Oleksy, Jill S. Baron, Peter Leavitt, Sarah Spaulding
Characterizing benthic macroinvertebrate and algal biological condition gradient models for California wadeable Streams, USA
The Biological Condition Gradient (BCG) is a conceptual model that describes changes in aquatic communities under increasing levels of anthropogenic stress. The BCG helps decision-makers connect narrative water quality goals (e.g., maintenance of natural structure and function) to quantitative measures of ecological condition by linking index thresholds based on statistical distributions (e.g., pe
Authors
Michael J. Paul, Ben Jessup, Larry R. Brown, James Carter, Marco Cantonati, Donald F. Charles, Jeroen Gerritsen, Dave Herbst, Rosalina Stancheva, Jeanette K. Howard, Bill Isham, Rex Lowe, Raphael D Mazor, Patina K. Mendez, Peter R Ode, Alison O'Dowd, Yangdong Pan, Andrew C. Rehn, Sarah A. Spaulding, Martha Sutula, Susanna Theroux
Reduction of taxonomic bias in diatom species data
Inconsistency in taxonomic identification and analyst bias impede the effective use of diatom data in regional and national stream and lake surveys. In this study, we evaluated the effect of existing protocols and a revised protocol on the precision of diatom species counts. The revised protocol adjusts four elements of sample preparation, taxon identification and enumeration, and quality control
Authors
Meredith Tyree, Ian W. Bishop, Charles P. Hawkins, Richard M. Mitchell, Sarah A. Spaulding
Diatom enumeration method influences biological assessments of southeastern USA streams
Current fixed-count enumeration methods for benthic diatoms are likely inadequate for most research and monitoring objectives. These methods underestimate taxa richness and may fail to detect losses of species caused by human impacts. Consequently, the full potential of diatoms is not realized in current assessments of biological integrity or species diversity. In this study, we hypothesize that a
Authors
Meredith Tyree, Daren M. Carlisle, Sarah Spaulding
Taxonomic harmonization may reveal a stronger association between diatom assemblages and total phosphorus in large datasets
Diatom data have been collected in large-scale biological assessments in the United States, such as the U.S. Environmental Protection Agency’s National Rivers and Streams Assessment (NRSA). However, the effectiveness of diatoms as indicators may suffer if inconsistent taxon identifications across different analysts obscure the relationships between assemblage composition and environmental variable
Authors
Sylvia S Lee, Ian W. Bishop, Sarah A. Spaulding, Richard M. Mitchell, Lester Yuan
A diatom voucher flora from selected southeast rivers (USA)
This flora is intended to serve as an image voucher for samples analyzed for the U.S. Geological Survey Southeast Stream Quality Assessment (SESQA). The SESQA study included measurement of watershed and water quality parameters to determine the factors that have the greatest potential to alter biotic condition. Algal samples were collected at 108 sites in 2014, from streams representing gradients
Authors
Ian W. Bishop, Rhea R.M. Esposito, Meredith Tyree, Sarah A. Spaulding
Non-USGS Publications**
Enache, M., Potapova, M.G., Tyree, M.A. and Spaulding, S.A. 2022. Aulacoseira novacaesarea sp. nov. (Bacillariophyta) a new centric diatom species from the northeastern United States. Diatom Research doi: 10.1080/0269249X.2022.2118834
Potapova, M.G., Lee, S.S., Spaulding, S.A. and Schulte, N.O. 2022. A harmonized dataset of sediment diatoms from hundreds of lakes in the northeast United States. Scientific Data-Nature 9:540 doi: 10.1038/s41597-022-01661-3
Li, D., Record, S., Sokol, E., Bitters, M.E., Chen, M.Y., Chung, Y.A., Helmus, M. Jaimes, R., Jansen, L., Jarzyna, M.A., Just, M.G., LaMontagne, J.M., Melbourne, B., Moss, W., Norman, K., Parker, S., Robinson, N., Seyednasrollah, B., Smith, C., Spaulding, S., Surasinghe, T., Thomsen, S., Zarnetske, P. 2022. Tidy NEON organismal data for biodiversity research. Ecosphere.
Nagy et al. 2021. Harnessing the NEON data revolution to advance open environmental science with a diverse and data-capable community. Ecosphere. doi: 10.1002/ecs2.3833
Hamsher, S.E., Kociolek, J.P., Spaulding, S.A. and Saleh, A.I. 2021. Taxonomy and nomenclature of members within the Obtusae section of Nitzschia Hassall (Bacillariophyceae) including descriptions of two new species. Fottea 2: 247-258. doi: 10.5507/fot.2021.010
Williams, D.M., Spaulding, S.A. and Bishop, I.W. 2021. Studies on type material from Kützing's diatom collection IV: The basionym, author and type of Tetracyclus rupestre. Phytotaxa. doi: 10.11646/phytotaxa.498.1.5
Benson, M.A., Smith, D.M. and Spaulding, S.A. 2021. Perspectives on the paleolimnology of the late Eocene Florissant lake from diatom and sedimentary records at Clare's Quarry, Teller County, Colorado, USA. Geological Society of America Proceedings. in Starratt, S.W. and Rosen, M.R., eds., From Saline to Freshwater: The Diversity of Western Lakes in Space and Time: Geological Society of America Special Paper 536.
Paul, M.J., Jessup, B., Brown, L., Carter, J., Cantonati, M., Charles, D.F., Gerritsen, J., Herbst, D., Hristova, R.S., Howard, J., Isham, B., Lowe, R., Mazor, R., Mendez, P., Ode, P., O'Dowd, A., Olson, J., Pan, Y., Rehn, A., Spaulding, S.A., Sutula, M. and Theroux, S. 2020. Characterizing benthic macroinvertebrate and algal biological condition gradient models for California wadeable streams, USA. Ecological Indicators 177: 106618. doi: 10.1016/j.ecolind.2020.106618
Meilijson, A., Hilgen, F., Sepúlveda, J., Steinberg, J., Flecker, R., Waldmann, N.D., Spaulding, S.A., Bialik, O.M., Ilner, P., Boudinot, F.G. and Makovsky, Y. 2019. Integrated stratigraphy of Messinian evaporites in the deep Eastern Mediterranean reveal long lasting halite deposition through Atlantic connectivity. Earth Science Reviews 194: 374-398
Lee, S.S., Bishop, I.W., Spaulding, S.A., Mitchell, R. and Yuan, L.L. 2019. Harmonization and revision of a national diatom dataset for use in the development of water quality indicators. Ecological Indicators 102:166-174.
Moser, J., Baron, J., Brahney, J., Olesky, I., Saros, J., Hundey, S., Sadro, S., Kopacek, Sommaruga, Kainze, Strecker, A., Chandra, D., Walters, D., Preston, Michelutti, N., Lepori, Spaulding, S., Hik, Christianson, Melack, J. and Smol, J. 2019. Mountain lakes: eyes on global environmental change. Global and Planetary Change 178: 77-95.
Bishop, I.W., Tucker, S.T., Joeckel, R.M. and Spaulding, S.A. 2018. Rare and diverse benthic fossil diatoms from the upper Ogallala Group (late Miocene) near Scotia, NE (USA) Nova Hedwigia, Beihefte 147: 261-294.
Bishop, I. and Spaulding, S.A. 2017. Seasonal population dynamics and size restoration in Didymosphenia geminata. Journal of Phycology 53: 652-663.
Spaulding, S.A. 2016. An uncertain synergy between atmospheric deposition and warming: high-elevation lakes of Grand Teton National Park. Mountain Views, Chronicles of the Consortium for Integrated Climate Research in Western Mountains 10(1)
Sakaeva, A., Stanish, L.F., Kohler, T.J., Spaulding, S.A., McKnight, D.M., Howkins, A., Welch, K.A., Lyons, W.B., Sokol, E.R. and Barrett, J.E. 2016. Evidence for dispersal and habitat controls on pond diatom communities in the McMurdo Sound Region of Antarctica. Polar Biology 1-16.
Bishop, I. and Spaulding, S.A. 2015. Tetracyclus hinziae (Bacillariophyta), a new species from the central Cascade Mountains (WA, USA). Phytotaxa 205(3). doi: 10.11646/phytotaxa.205.3.7
Bergey, E.A. and Spaulding. S.A. 2015. Didymosphenia: it’s more complicated. A response to the Forum article by Taylor and Bothwell (2014). Bioscience doi:10.1093/biosci/biu226
Cullis, J.D.S., McKnight, D.M. and Spaulding, S.A. 2015. Hydrodynamic control of benthic mats of Didymosphenia geminata at the reach scale. Canadian Journal of Fisheries and Aquatic Sciences 72(6): 902-914.
Personius, S.F., Briggs, R.W., Nelson, A.R., Schermer, E.R., Maharrey, J.Z., Sherrod, B.L., Spaulding, S.A. and Bradley, L. 2014. Holocene earthquakes and right-lateral slip on the left-lateral Darrington–Devils Mountain fault zone, northern Puget Sound, Washington. Geosphere doi: 10.1130/GES01067.1
Brahney, J., Spaulding, S, Ballantyne, A.P., Otu, M., Neff, J.C. 2014. Separating the influences of diagenesis, productivity, and anthropogenic nitrogen deposition on sedimentary d15N variations. Organic Geochemistry 75: 140-150.
Kociolek, J.P., Spaulding, S.A. and Lowe, R. 2015. Symmetrical Naviculoid Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Second Edition. Academic Press.
Brahney, J., Ballantyne, A., Kociolek, J.P., Spaulding, S.A., Otu, M., Porwall, T. and Neff, J.C. 2014. Dust mediated transfer of phosphorus to alpine lake ecosystems of the Wind River Range, Wyoming, USA. Biogeochemistry 120: 259-278.
Nakov, T., Ruck, E.C., Galachyants, Y., Spaulding, S.A. and Theriot, E. 2014. Molecular phylogeny of the Cymbellales (Heterokonthophyta: Bacillariophyceae) with a comparison of models for accommodating rate-variation across sites. Phycologia 53 (4): 359–373.
Benson, M.E., Kociolek, J.P., Spaulding, S.A., and Smith, D.M. 2012. Pre-Neogene (>23.8 MA) biochronology of non-marine diatoms, with an account of the late Eocene flora of the Florissant Formation, central Colorado, USA. Stratigraphy 9: 131-152.
Spaulding, S.A., Jewson, D., Bixby, R., Nelson, H. and McKnight, D.M. 2012. Automated measurement of diatom size. Limnology and Oceanography: Methods 10: 882-890.
Reid, B.L., Hernandez, K.L., Frangopoulis, M., Bauer, G., Lorca, M., Kilroy, C. and Spaulding, S.A. 2012. The invasion of the freshwater diatom Didymosphenia geminata in Patagonia: prospects, strategies, and implications for biosecurity of invasive species in continental waters. Conservation Letters doi: 10.1111/j.1755-263X.2012.00264.
Stanish, L.F., O’Neill, S.P., Gonzalez-Peña, A., Legg, T.M., Knelman, J., McKnight, D.M., Spaulding, S. and Nemergut, D.R. 2012. Bacterial-diatom community and co-occurrence relationships exist in microbial mats from polar desert streams. Environmental Microbiology doi: 10.1111/j.1462-2920.2012.02872.x.
Sundareshwar, P.V., Upadhayay, S., Abessa, M., Honomichl, S., Berdanier, B., Spaulding, S.A., Sandvik, C. and Trennepohl, A. 2011. Didymosphenia geminata: algal blooms in oligotrophic streams and rivers. Geophysical Research Letters 38: L10405, doi:10.1029/2010GL046599.
Spaulding, S.A., McKnight, D.M., Stanish, L., Van de Vijver, B. and Hodgson, D. 2010. Diatoms as indicators of environmental change in Antarctic and Sub-Antarctic freshwaters. In: Smol, J. and E.F. Stoermer (eds). The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, Cambridge pp. 267-286.
Spaulding, S.A., Kilroy, C. and Edlund, M. 2010. Diatoms as invasive species. In: Smol, J. and E.F. Stoermer (eds). The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, Cambridge pp. 560-569.
Rushforth, S.J., Edlund, M.B., Spaulding, S.A. and Stoermer, E.F. 2010. The Reimer Diatom Herbarium: an important resource for teaching and research. Proceedings of the Academy of Natural Sciences of Philadelphia.
Spaulding, S.A., Pool, J.R., Castro, S.I. and Hinz. 2010. Notes on species within the genus Encyonema Kützing, including two new species Encyonema reimeri sp. nov. and E. nickcafei sp. nov. and E. stoermeri nom. nov., stat. nov. Proceedings of the Academy of Natural Sciences of Philadelphia.
Morales, E.A., Edlund, M.B. and Spaulding, S.A. 2010. Description and ultrastructure of fragilarioid diatom species (Bacillariophyceae) morphologically similar to Pseudostaurosira elliptica (Schumann) Edlund et al. Phycological Research 58: 97-107.
Van de Vijver, B., Mataloni, G., Stanish L. and Spaulding, S.A. 2010. New and interesting species of the genus Muelleria (Bacillariophyta) from the Antarctic Region and South Africa. Phycologia 49: 22-41.
Pite, D., Lane, K., Hermann, A, Spaulding, S.A. and Finney, B. 2009. Historical abundance and morphology of Didymosphenia geminata in Naknek Lake, Alaska. Acta Bot. Croat. 68: 183-197.
Kumar, S., Spaulding, S.A., Stohlgren, T., Hermann, K., Schmidt, T. and Bahls, L. 2009. Modelling the bioclimatic profile of the diatom Didymosphenia geminata. Frontiers in Ecology and the Environment. 8: 415-420.
Esposito, R.M.M., Spaulding, S.A., McKnight, D.M. , Lubinski, D. , Hall, B. , and Whittaker, T. 2008. Inland diatoms from the McMurdo Dry Valleys, Antarctica. Botany 86: 1378-1392.
Whittaker, T.E, Hall, B.L., Hendy, C.H. and Spaulding, S.A. 2008. Holocene surface-level changes and depositional environments at Lake Fryxell, Antarctica. The Holocene 18(5): 775-786.
Bothwell, M.L. and Spaulding, S.A. 2008. Synopsis: the 2007 International workshop on Didymosphenia geminata. Canadian Technical Report of Fisheries and Aquatic Sciences 2795.
Spaulding, S.A., Hermann, K.A. and Johnson, T. 2008. Confirmed distribution of Didymosphenia geminata (Lyngbye) Schmidt in North America. Proceedings, 2007 International Workshop on Didymosphenia geminata, Canadian Technical Report of Fisheries and Aquatic Sciences 2795.
Esposito, R. M. M., S. L. Horn, D. M. McKnight, M. J. Cox, M. C. Grant, S. A. Spaulding, P. T. Doran, and K. D. Cozzetto 2006. Antarctic climate cooling and response of diatoms in glacial meltwater streams, Geophys. Res. Lett., 33.
Edlund, M.B., E.A. Morales and S.A. Spaulding. 2006. The type and taxonomy of Fragilaria elliptica Schumann, a widely misconstrued taxon. Proceedings of the International Society of Diatom Research.
Edlund, M.B. and S.A. Spaulding. 2006. Restoration of maximum cell size by uniparental auxosporulation in Scoliopleura Grunow and Muelleria (Frenguelli) Frenguelli. In: Ognjanova-Rumenova and Manoylov (eds.), Fossil and Recent Phycological Studies, pp. 211-223
Kociolek, J.P., S.A. Spaulding, K. Sabbe, and W. Vyverman. 2004. New Gomphonema (Bacillariophyta) species from Tasmania. Phycologia 43:427-444.
Spaulding, S.A., A. Akbulut and J.P. Kociolek 2003. A new species of Aneumastus Mann and Stickle from Central Turkey. Diatom Research 18:149-160.
Kociolek, J.P. and S.A. Spaulding. 2002. Evolutionary relationships, species concepts and implications of two disparate freshwater, fossil centric diatoms (Bacillariophyta) from western North America. Journal of Phycology 38: 821-833.
Kociolek, J.P. and S.A. Spaulding. 2002. Symmetrical Naviculoid Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Academic Press. pp. 637-651.
Kociolek, J.P. and S.A. Spaulding. 2002. Eunotiod and Asymmetrical Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Academic Press. pp. 655-666.
Spaulding, S.A. and J.P. Kociolek. 2003. Freshwater diatoms (Bacillariophyceae) In: Goodman, S. and Benstead, J. (eds). Natural History of Madagascar, University of Chicago Press.
Spaulding, S.A., J.P. Kociolek and D. Davis. 2002. A new diatom genus from a playa lake in New Mexico, USA with the description of two new species. European Journal of Phycology 37: 135-143.
Stoermer, E.F, M. Julius, J.P. Kociolek and S.A. Spaulding. 2002. Centric Diatoms. In: Sheath, R. and Wehr, J. (eds). Freshwater Algae of North America, Academic Press. pp. 559-562.
Strelnikova, N.I., E. Fourtanier, J.A. Barron, J.P. Kociolek, A. Mahood and S.A. Spaulding (2002). A species of the genus Coscinodiscus Ehrenberg from the Eocene of California. Proceedings of the 15th International Diatom Symposium, Ganter Verlag, Liechtenstein. pp. 359-380.
Kociolek, J.P., D. Lyon and S. Spaulding 2001. Revision of the South American species of Actinella In: Jahn, R., Kociolek, J.P., Witkowski , A. and Compère P. (eds). Lange-Bertalot-Festschrift: Studies on Diatoms, Koeltz Scientific Books, Koenigstein. pp. 131-166.
Kociolek, J.P. and S.A. Spaulding. 1999. Freshwater diatom biogeography. Nova Hedwigia 71: 223-241.
Spaulding, S.A., J.P. Kociolek and D. Wong. 1999. A taxonomic and systematic revision of the genus Muelleria (Bacillariophyta). Phycologia 38: 314-341.
Spaulding, S.A. and J.P. Kociolek. 1998. New Gomphonema species from Madagascar. Proceedings of the California Academy of Sciences 50: 361-379.
Spaulding, S.A. and J.P. Kociolek. 1998. The diatom genus Orthoseira: Ultrastructure and morphological variation in two species from Madagascar with comments on nomenclature in the genus. Diatom Research 13: 133-147.
Kociolek, J.P., S.A. Spaulding and J.C. Kingston. 1998. Valve morphology and systematic position of Navicula walkeri Sovereign, a diatom endemic to Oregon and California (USA) freshwaters. Nova Hedwigia.
Spaulding, S.A. and D. McKnight. 1998. Diatoms as Indicators of Environmental Change in Antarctic Freshwaters. In: Smol, J. and E.F. Stoermer (eds). The Diatoms: Applications for the Environmental and Earth Sciences. Cambridge University Press, Cambridge. pp. 249-263.
McKnight, D.M., A. Alger, C.M. Tate, G. Shupe and S.A. Spaulding. 1997. Longitudinal patterns in algal abundance and species distribution in meltwater streams in Taylor Valley, Southern Victorialand, Antarctica. In: Priscu, J. (ed.). American Geophysical Union, Antarctic Research Series.
Fountain, A. and S.A. Spaulding. 1997. Researchers pool knowledge about Antarctic Dry Valleys. EOS, Transactions, American Geophysical Union 78: 295-298.
Spaulding, S.A. and E.F. Stoermer. 1997. Taxonomy and distribution of the genus Muelleria Frenguelli. Diatom Research 12: 95-113.
Spaulding, S.A., D. McKnight, E.F. Stoermer and P.T. Doran. 1997. Sedimentary record of diatoms in Lake Hoare, Antarctica. Journal of Paleolimnology 17: 403-420.
Laybourn-Parry, J., M. James, D. McKnight, J. Priscu, S.A. Spaulding and R.Shiel. 1997. The microbial plankton of Lake Fryxell, southern Victoria Land, Antarctica during the summers of 1992 and 1994. Polar Biology 17: 54-61.
Spaulding, S.A. 1996. Algal investigations at varying temporal scales in an extreme environment: McMurdo Dry Valleys lakes, Antarctica. Ph. D. Thesis, Colorado State University.
McKnight, D.M., E.D. Andrews, S.A. Spaulding and G.R. Aiken. 1994. Aquatic fulvic acids in eutrophic coastal ponds in Antarctica and comparison with other aquatic fulvic acids. Limnology and Oceanography 39:1972-1979.
Spaulding, S.A., D.M. McKnight and R.L. Smith. 1994. Temporal dynamics of phytoplankton populations in perennially ice-covered Lake Fryxell. Journal of Plankton Research 16: 527-541.
Spaulding, S.A, J.V. Ward and J. Baron. 1993. Winter phytoplankton dynamics in a subalpine lake. Archiv für Hydrobiology 129: 179-198.
Spaulding, S.A., M.A. Harris, D.M. McKnight and B.D. Rosenlund. 1991. Aquatic Biota. In: J. Baron, Biogeochemisty of Loch Vale Watershed. Springer-Verlag, New York.
McKnight, D., R.L. Smith, J.P. Bradbury, J. Baron and S.A. Spaulding. 1990. Phytoplankton dynamics in three Rocky Mountain lakes. Arctic and Alpine Research 22: 264-274.
**Disclaimer: The views expressed in Non-USGS publications are those of the author and do not represent the views of the USGS, Department of the Interior, or the U.S. Government.
*Disclaimer: Listing outside positions with professional scientific organizations on this Staff Profile are for informational purposes only and do not constitute an endorsement of those professional scientific organizations or their activities by the USGS, Department of the Interior, or U.S. Government