Search Results - "McKnight, D M"

Environmental and Agricultural Relevance of Humic Fractions Extracted by Alkali from Soils and Natural Waters by Olk, D. C., Bloom, P. R., Perdue, E. M., McKnight, D. M., Chen, Y., Farenhorst, A., Senesi, N., Chin, Y.‐P., Schmitt‐Kopplin, P., Hertkorn, N., Harir, M.

“…To study the structure and function of soil organic matter, soil scientists have performed alkali extractions for soil humic acid (HA) and fulvic acid (FA)…”
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Microbial formation of labile organic carbon in Antarctic glacial environments by Smith, H. J., Foster, R. A., McKnight, D. M., Lisle, J. T., Littmann, S., Kuypers, M. M. M., Foreman, C. M.

“…Roughly six petagrams of organic carbon are stored within ice worldwide. This organic carbon is thought to be of old age and highly bioavailable. Along with…”
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Relationship between dissolved organic matter quality and microbial community composition across polar glacial environments by Smith, H J, Dieser, M, McKnight, D M, SanClements, M D, Foreman, C M

“…Vast expanses of Earth's surface are covered by ice, with microorganisms in these systems affecting local and global biogeochemical cycles. We examined…”
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Freshwater diatom biogeography and the genus Luticola: an extreme case of endemism in Antarctica by Kociolek, J. P., Kopalová, K., Hamsher, S. E., Kohler, T. J., Van de Vijver, B., Convey, P., McKnight, D. M.

“…Historical views have characterized Antarctica as a frozen desert with low diversity, although recent studies suggest that this may not be true for microscopic…”
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Impact of meltwater flow intensity on the spatiotemporal heterogeneity of microbial mats in the McMurdo Dry Valleys, Antarctica by Zoumplis, A, Kolody, B, Kaul, D, Zheng, H, Venepally, P, McKnight, D M, Takacs-Vesbach, C, DeVries, A, Allen, A E

“…The meltwater streams of the McMurdo Dry Valleys are hot spots of biological diversity in the climate-sensitive polar desert landscape. Microbial mats, largely…”
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Biogeochemical stoichiometry of Antarctic Dry Valley ecosystems by Barrett, J. E., Virginia, R. A., Lyons, W. B., McKnight, D. M., Priscu, J. C., Doran, P. T., Fountain, A. G., Wall, D. H., Moorhead, D. L.

“…Among aquatic and terrestrial landscapes of the McMurdo Dry Valleys, Antarctica, ecosystem stoichiometry ranges from values near the Redfield ratios for C:N:P…”
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Environmental factors influencing diatom communities in Antarctic cryoconite holes by Stanish, L F, Bagshaw, E A, McKnight, D M, Fountain, A G, Tranter, M

“…Cryoconite holes are ice-bound habitats that can act as refuges for aquatic and terrestrial microorganisms on glacier surfaces. In the McMurdo Dry Valleys of…”
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Alpine Lake Optical Properties as Sentinels of Dust Deposition and Global Change by Mladenov, N., López-Ramos, J., McKnight, D. M., Reche, I.

“…We characterized dissolved organic matter in La Caldera, an alpine lake in Sierra Nevada (Spain), and water-soluble organic compounds (WSOC) in dry and wet…”
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Antarctic climate cooling and response of diatoms in glacial meltwater streams by Esposito, R. M. M., Horn, S. L., McKnight, D. M., Cox, M. J., Grant, M. C., Spaulding, S. A., Doran, P. T., Cozzetto, K. D.

“…To understand biotic responses to an Antarctic cooling trend, we analyzed diatom samples from glacial meltwater streams in the McMurdo Dry Valleys, the largest…”
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Reactivation of a cryptobiotic stream ecosystem in the McMurdo Dry Valleys, Antarctica: A long-term geomorphological experiment by McKnight, D.M., Tate, C.M., Andrews, E.D., Niyogi, D.K., Cozzetto, K., Welch, K., Lyons, W.B., Capone, D.G.

“…The McMurdo Dry Valleys of Antarctica contain many glacial meltwater streams that flow for 6 to 12 weeks during the austral summer and link the glaciers to the…”
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The ecology of pulse events: insights from an extreme climatic event in a polar desert ecosystem by Nielsen, U. N, Wall, D. H, Adams, B. J, Virginia, R. A, Ball, B. A, Gooseff, M. N, McKnight, D. M

“…Climate change is occurring globally, with wide ranging impacts on organisms and ecosystems alike. While most studies focus on increases in mean temperatures…”
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The carbon stable isotope biogeochemistry of streams, Taylor Valley, Antarctica by Lyons, W.B., Leslie, D.L., Harmon, R.S., Neumann, K., Welch, K.A., Bisson, K.M., McKnight, D.M.

“…► δ13C-DIC reported from McMurdo Dry Valleys, Antarctica, streams. ► Stream water δ13CPDB values range −9.4‰ to +5.1‰, largely inorganic in character. ►…”
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Effects of asynchronous snowmelt on flushing of dissolved organic carbon: a mixing model approach by Boyer, E. W., Hornberger, G. M., Bencala, K. E., McKnight, D. M.

“…In many snowmelt‐dominated catchments, stream dissolved organic carbon (DOC) levels typically increase rapidly as spring melt commences, peak before maximum…”
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The relationship between soil heterotrophic activity, soil dissolved organic carbon (DOC) leachate, and catchment-scale DOC export in headwater catchments by Brooks, P. D., McKnight, D. M., Bencala, K. E.

“…Dissolved organic carbon (DOC) from terrestrial sources forms the major component of the annual carbon budget in many headwater streams. In high‐elevation…”
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Simulation of DOM fluxes in a seasonal floodplain of the Okavango Delta, Botswana by Mladenov, N., McKnight, D.M., Wolski, P., Murray-Hudson, M.

“…In order to examine dissolved organic matter (DOM) fluxes in seasonal wetland systems that expand and contract seasonally, a time-variable model of dissolved…”
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Quinone Moieties Act as Electron Acceptors in the Reduction of Humic Substances by Humics-Reducing Microorganisms by Scott, Durelle T, McKnight, Diane M, Blunt-Harris, Elizabeth L, Kolesar, Sarah E, Lovley, Derek R

“…The possibility that quinones serve as electron-accepting moieties when microorganisms transfer electrons to humic substances was investigated. Humic…”
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Using Humic Fractions to Understand Natural Organic Matter Processes in Soil and Water: Selected Studies and Applications by Olk, D. C., Bloom, P. R., De Nobili, M., Chen, Y., McKnight, D. M., Wells, M. J. M., Weber, J.

“…Natural organic matter (NOM) plays key environmental roles in both aquatic and soil systems. A long‐standing approach for evaluating NOM composition and…”
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Hydrological Controls on Dissolved Organic Carbon during Snowmelt in the Snake River near Montezuma, Colorado by Hornberger, G. M., Bencala, K. E., McKnight, D. M.

“…A quantitative understanding of the factors controlling the variation of dissolved organic carbon (DOC) in headwater streams is of scientific concern for at…”
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Transit Times and Rapid Chemical Equilibrium Explain Chemostasis in Glacial Meltwater Streams in the McMurdo Dry Valleys, Antarctica by Wlostowski, A. N., Gooseff, M. N., McKnight, D. M., Lyons, W. B.

“…Fluid transit time is understood to be an important control on the shape of concentration‐discharge (C‐q) relationships, yet empirical evidence supporting this…”
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Response characteristics of DOC flushing in an alpine catchment by Boyer, Elizabeth W., Hornberger, George M., Bencala, Kenneth E., McKnight, Diane M.

“…The spatial distribution of source areas and associated residence times of water in the catchment are significant factors controlling the annual cycles of…”
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