Articles | Volume 16, issue 5
https://doi.org/10.5194/tc-16-1889-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
https://doi.org/10.5194/tc-16-1889-2022
© Author(s) 2022. This work is distributed under
the Creative Commons Attribution 4.0 License.
the Creative Commons Attribution 4.0 License.
Research article
| 
19 May 2022
Research article |
| 19 May 2022
| 19 May 2022
High nitrate variability on an Alaskan permafrost hillslope dominated by alder shrubs
Rachael E. McCaully
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Department of Marine Earth and Atmospheric Sciences, North Carolina
State University, Raleigh, 27695, United States
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Department of Marine Earth and Atmospheric Sciences, North Carolina
State University, Raleigh, 27695, United States
Brent D. Newman
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Verity G. Salmon
Environmental Sciences Division and Climate Change Science Institute,
Oak Ridge National Laboratory, Oak Ridge, 37830, United States
Jeffrey M. Heikoop
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Cathy J. Wilson
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Sanna Sevanto
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Nathan A. Wales
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
George B. Perkins
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Oana C. Marina
Earth and Environmental Sciences Division, Los Alamos National
Laboratory, Los Alamos, 87545, United States
Stan D. Wullschleger
Environmental Sciences Division and Climate Change Science Institute,
Oak Ridge National Laboratory, Oak Ridge, 37830, United States
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Boreal peatlands store much of the global soil carbon, a service dependent on nutrient limitation on plant productivity. This study improved a major land surface model to better represent how plants gain nitrogen and phosphorus through fine roots and mycorrhizal association. The new model more accurately captured observed carbon fluxes than the default model at an experimental site in Minnesota, and suggests shifts in nutrient uptake strategy helps peatlands stay carbon-rich under warming.
Charles E. Miller, Peter C. Griffith, Elizabeth Hoy, Naiara S. Pinto, Yunling Lou, Scott Hensley, Bruce D. Chapman, Jennifer Baltzer, Kazem Bakian-Dogaheh, W. Robert Bolton, Laura Bourgeau-Chavez, Richard H. Chen, Byung-Hun Choe, Leah K. Clayton, Thomas A. Douglas, Nancy French, Jean E. Holloway, Gang Hong, Lingcao Huang, Go Iwahana, Liza Jenkins, John S. Kimball, Tatiana Loboda, Michelle Mack, Philip Marsh, Roger J. Michaelides, Mahta Moghaddam, Andrew Parsekian, Kevin Schaefer, Paul R. Siqueira, Debjani Singh, Alireza Tabatabaeenejad, Merritt Turetsky, Ridha Touzi, Elizabeth Wig, Cathy J. Wilson, Paul Wilson, Stan D. Wullschleger, Yonghong Yi, Howard A. Zebker, Yu Zhang, Yuhuan Zhao, and Scott J. Goetz
Earth Syst. Sci. Data, 16, 2605–2624, https://doi.org/10.5194/essd-16-2605-2024, https://doi.org/10.5194/essd-16-2605-2024, 2024
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NASA’s Arctic Boreal Vulnerability Experiment (ABoVE) conducted airborne synthetic aperture radar (SAR) surveys of over 120 000 km2 in Alaska and northwestern Canada during 2017, 2018, 2019, and 2022. This paper summarizes those results and provides links to details on ~ 80 individual flight lines. This paper is presented as a guide to enable interested readers to fully explore the ABoVE L- and P-band SAR data.
Nathan Alec Conroy, Jeffrey M. Heikoop, Emma Lathrop, Dea Musa, Brent D. Newman, Chonggang Xu, Rachael E. McCaully, Carli A. Arendt, Verity G. Salmon, Amy Breen, Vladimir Romanovsky, Katrina E. Bennett, Cathy J. Wilson, and Stan D. Wullschleger
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This study combines field observations, non-parametric statistical analyses, and thermodynamic modeling to characterize the environmental causes of the spatial variability in soil pore water solute concentrations across two Arctic catchments with varying extents of permafrost. Vegetation type, soil moisture and redox conditions, weathering and hydrologic transport, and mineral solubility were all found to be the primary drivers of the existing spatial variability of some soil pore water solutes.
Katrina E. Bennett, Greta Miller, Robert Busey, Min Chen, Emma R. Lathrop, Julian B. Dann, Mara Nutt, Ryan Crumley, Shannon L. Dillard, Baptiste Dafflon, Jitendra Kumar, W. Robert Bolton, Cathy J. Wilson, Colleen M. Iversen, and Stan D. Wullschleger
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In the Arctic and sub-Arctic, climate shifts are changing ecosystems, resulting in alterations in snow, shrubs, and permafrost. Thicker snow under shrubs can lead to warmer permafrost because deeper snow will insulate the ground from the cold winter. In this paper, we use modeling to characterize snow to better understand the drivers of snow distribution. Eventually, this work will be used to improve models used to study future changes in Arctic and sub-Arctic snow patterns.
Elchin E. Jafarov, Daniil Svyatsky, Brent Newman, Dylan Harp, David Moulton, and Cathy Wilson
The Cryosphere, 16, 851–862, https://doi.org/10.5194/tc-16-851-2022, https://doi.org/10.5194/tc-16-851-2022, 2022
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Recent research indicates the importance of lateral transport of dissolved carbon in the polygonal tundra, suggesting that the freeze-up period could further promote lateral carbon transport. We conducted subsurface tracer simulations on high-, flat-, and low-centered polygons to test the importance of the freeze–thaw cycle and freeze-up time for tracer mobility. Our findings illustrate the impact of hydraulic and thermal gradients on tracer mobility, as well as of the freeze-up time.
Karis J. McFarlane, Heather M. Throckmorton, Jeffrey M. Heikoop, Brent D. Newman, Alexandra L. Hedgpeth, Marisa N. Repasch, Thomas P. Guilderson, and Cathy J. Wilson
Biogeosciences, 19, 1211–1223, https://doi.org/10.5194/bg-19-1211-2022, https://doi.org/10.5194/bg-19-1211-2022, 2022
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Planetary warming is increasing seasonal thaw of permafrost, making this extensive old carbon stock vulnerable. In northern Alaska, we found more and older dissolved organic carbon in small drainages later in summer as more permafrost was exposed by deepening thaw. Younger and older carbon did not differ in chemical indicators related to biological lability suggesting this carbon can cycle through aquatic systems and contribute to greenhouse gas emissions as warming increases permafrost thaw.
Yaoping Wang, Jiafu Mao, Mingzhou Jin, Forrest M. Hoffman, Xiaoying Shi, Stan D. Wullschleger, and Yongjiu Dai
Earth Syst. Sci. Data, 13, 4385–4405, https://doi.org/10.5194/essd-13-4385-2021, https://doi.org/10.5194/essd-13-4385-2021, 2021
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We developed seven global soil moisture datasets (1970–2016, monthly, half-degree, and multilayer) by merging a wide range of data sources, including in situ and satellite observations, reanalysis, offline land surface model simulations, and Earth system model simulations. Given the great value of long-term, multilayer, gap-free soil moisture products to climate research and applications, we believe this paper and the presented datasets would be of interest to many different communities.
Dylan R. Harp, Vitaly Zlotnik, Charles J. Abolt, Bob Busey, Sofia T. Avendaño, Brent D. Newman, Adam L. Atchley, Elchin Jafarov, Cathy J. Wilson, and Katrina E. Bennett
The Cryosphere, 15, 4005–4029, https://doi.org/10.5194/tc-15-4005-2021, https://doi.org/10.5194/tc-15-4005-2021, 2021
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Polygon-shaped landforms present in relatively flat Arctic tundra result in complex landscape-scale water drainage. The drainage pathways and the time to transition from inundated conditions to drained have important implications for heat and carbon transport. Using fundamental hydrologic principles, we investigate the drainage pathways and timing of individual polygons, providing insights into the effects of polygon geometry and preferential flow direction on drainage pathways and timing.
Rafael Poyatos, Víctor Granda, Víctor Flo, Mark A. Adams, Balázs Adorján, David Aguadé, Marcos P. M. Aidar, Scott Allen, M. Susana Alvarado-Barrientos, Kristina J. Anderson-Teixeira, Luiza Maria Aparecido, M. Altaf Arain, Ismael Aranda, Heidi Asbjornsen, Robert Baxter, Eric Beamesderfer, Z. Carter Berry, Daniel Berveiller, Bethany Blakely, Johnny Boggs, Gil Bohrer, Paul V. Bolstad, Damien Bonal, Rosvel Bracho, Patricia Brito, Jason Brodeur, Fernando Casanoves, Jérôme Chave, Hui Chen, Cesar Cisneros, Kenneth Clark, Edoardo Cremonese, Hongzhong Dang, Jorge S. David, Teresa S. David, Nicolas Delpierre, Ankur R. Desai, Frederic C. Do, Michal Dohnal, Jean-Christophe Domec, Sebinasi Dzikiti, Colin Edgar, Rebekka Eichstaedt, Tarek S. El-Madany, Jan Elbers, Cleiton B. Eller, Eugénie S. Euskirchen, Brent Ewers, Patrick Fonti, Alicia Forner, David I. Forrester, Helber C. Freitas, Marta Galvagno, Omar Garcia-Tejera, Chandra Prasad Ghimire, Teresa E. Gimeno, John Grace, André Granier, Anne Griebel, Yan Guangyu, Mark B. Gush, Paul J. Hanson, Niles J. Hasselquist, Ingo Heinrich, Virginia Hernandez-Santana, Valentine Herrmann, Teemu Hölttä, Friso Holwerda, James Irvine, Supat Isarangkool Na Ayutthaya, Paul G. Jarvis, Hubert Jochheim, Carlos A. Joly, Julia Kaplick, Hyun Seok Kim, Leif Klemedtsson, Heather Kropp, Fredrik Lagergren, Patrick Lane, Petra Lang, Andrei Lapenas, Víctor Lechuga, Minsu Lee, Christoph Leuschner, Jean-Marc Limousin, Juan Carlos Linares, Maj-Lena Linderson, Anders Lindroth, Pilar Llorens, Álvaro López-Bernal, Michael M. Loranty, Dietmar Lüttschwager, Cate Macinnis-Ng, Isabelle Maréchaux, Timothy A. Martin, Ashley Matheny, Nate McDowell, Sean McMahon, Patrick Meir, Ilona Mészáros, Mirco Migliavacca, Patrick Mitchell, Meelis Mölder, Leonardo Montagnani, Georgianne W. Moore, Ryogo Nakada, Furong Niu, Rachael H. Nolan, Richard Norby, Kimberly Novick, Walter Oberhuber, Nikolaus Obojes, A. Christopher Oishi, Rafael S. Oliveira, Ram Oren, Jean-Marc Ourcival, Teemu Paljakka, Oscar Perez-Priego, Pablo L. Peri, Richard L. Peters, Sebastian Pfautsch, William T. Pockman, Yakir Preisler, Katherine Rascher, George Robinson, Humberto Rocha, Alain Rocheteau, Alexander Röll, Bruno H. P. Rosado, Lucy Rowland, Alexey V. Rubtsov, Santiago Sabaté, Yann Salmon, Roberto L. Salomón, Elisenda Sánchez-Costa, Karina V. R. Schäfer, Bernhard Schuldt, Alexandr Shashkin, Clément Stahl, Marko Stojanović, Juan Carlos Suárez, Ge Sun, Justyna Szatniewska, Fyodor Tatarinov, Miroslav Tesař, Frank M. Thomas, Pantana Tor-ngern, Josef Urban, Fernando Valladares, Christiaan van der Tol, Ilja van Meerveld, Andrej Varlagin, Holm Voigt, Jeffrey Warren, Christiane Werner, Willy Werner, Gerhard Wieser, Lisa Wingate, Stan Wullschleger, Koong Yi, Roman Zweifel, Kathy Steppe, Maurizio Mencuccini, and Jordi Martínez-Vilalta
Earth Syst. Sci. Data, 13, 2607–2649, https://doi.org/10.5194/essd-13-2607-2021, https://doi.org/10.5194/essd-13-2607-2021, 2021
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Transpiration is a key component of global water balance, but it is poorly constrained from available observations. We present SAPFLUXNET, the first global database of tree-level transpiration from sap flow measurements, containing 202 datasets and covering a wide range of ecological conditions. SAPFLUXNET and its accompanying R software package
sapfluxnetrwill facilitate new data syntheses on the ecological factors driving water use and drought responses of trees and forests.
Debjani Sihi, Xiaofeng Xu, Mónica Salazar Ortiz, Christine S. O'Connell, Whendee L. Silver, Carla López-Lloreda, Julia M. Brenner, Ryan K. Quinn, Jana R. Phillips, Brent D. Newman, and Melanie A. Mayes
Biogeosciences, 18, 1769–1786, https://doi.org/10.5194/bg-18-1769-2021, https://doi.org/10.5194/bg-18-1769-2021, 2021
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Humid tropical soils are important sources and sinks of methane. We used model simulation to understand how different kinds of microbes and observed soil moisture and oxygen dynamics contribute to production and consumption of methane along a wet tropical hillslope during normal and drought conditions. Drought alters the diffusion of oxygen and microbial substrates into and out of soil microsites, resulting in enhanced methane release from the entire hillslope during drought recovery.
A. D. Collins, C. G. Andresen, L. M. Charsley-Groffman, T. Cochran, J. Dann, E. Lathrop, G. J. Riemersma, E. M. Swanson, A. Tapadinhas, and C. J. Wilson
Int. Arch. Photogramm. Remote Sens. Spatial Inf. Sci., XLIV-M-2-2020, 1–8, https://doi.org/10.5194/isprs-archives-XLIV-M-2-2020-1-2020, https://doi.org/10.5194/isprs-archives-XLIV-M-2-2020-1-2020, 2020
Cited articles
Baldwin, D. S. and Mitchell, A. M.: The effects of drying and re-flooding
on the sediment and soil nutrient dynamics of lowland river-floodplain
systems: A synthesis, Regul. Rivers: Res. Mgmt., 16, 457–467,
https://doi.org/10.1002/1099-1646(200009/10)16:5<457::AID-RRR597>3.0.CO;2-B, 2000.
Barnes, R. T., Williams, M. W., Parman, J. N., Hill, K., and Caine, N.:
Thawing glacial and permafrost features contribute to nitrogen export from
Green Lakes Valley, Colorado Front Range, USA, Biogeochemistry, 117,
413–430, https://doi.org/10.1007/s10533-013-9886-5, 2014.
Bechtold, J. S., Edwards, R. T., and Naiman R. J.: Biotic versus hydrologic
control over seasonal nitrate leaching in a floodplain forest,
Biogeochemistry, 63, 53–72, https://doi.org/10.1023/A:1023350127042, 2003.
Bernal, S., Butturini, A., Nin, E., Sabater, F., and Sabater, S.: Leaf
litter dynamics and nitrous oxide emission in a Mediterranean riparian
forest, J. Environ. Qual., 32, 191–197,
https://doi.org/10.2134/jeq2003.1910, 2003.
Boike, J., Juszak, I., Lange, S., Chadburn, S., Burke, E., Overduin, P. P., Roth, K., Ippisch, O., Bornemann, N., Stern, L., Gouttevin, I., Hauber, E., and Westermann, S.: A 20-year record (1998–2017) of permafrost, active layer and meteorological conditions at a high Arctic permafrost research site (Bayelva, Spitsbergen), Earth Syst. Sci. Data, 10, 355–390, https://doi.org/10.5194/essd-10-355-2018, 2018.
Bühlmann, T., Hiltbrunner, E., and Körner, C.: Alnus viridis expansion
contributes to excess reactive nitrogen release, reduces biodiversity and
constrains forest succession in the Alps, Alp. Bot., 124, 187–191,
https://doi.org/10.1007/s00035-014-0134-y, 2014.
Callahan, M. K., Whigham, D. F., Rain, M. C., Rains, K. C., King, R. S.,
Walker, C. M., Maurer, J. R., and Baird, D. J.: Nitrogen subsidies from
hillslope alder stands to streamside wetlands and headwater streams, Kenai
Peninsula, Alaska, JAWRA, 53, 478–492,
https://doi.org/10.1111/1752-1688.12508, 2017.
Chapin, F. S., Mcguire, A., D., Randerson, J., Pielke, R., Baldocchi, D.,
Hobbie, S. E., Roulet, N., Eugster, W., Kasischke, E., Rastetter, E. B.,
Zimov, A., and Running, S. W.: Arctic and boreal ecosystems of western North
America as components of the climate system, Glob. Chang. Biol., 6,
211–223, https://doi.org/10.1046/j.1365-2486.2000.06022.x, 2000.
Darrouzet-Nardi, A. and Weintraub, M. N.: Evidence for spatially
inaccessible labile N from a comparison of soil core extractions and soil
pore water lysimetry, Soil Biol. Biochem., 73, 22–32,
https://doi.org/10.1016/j.soilbio.2014.02.010, 2014.
Frost, G. V. and Epstein, H. E.: Tall shrub and tree expansion in Siberian
tundra ecotones since the 1960s, Glob. Chang. Biol., 20, 1264–1277,
https://doi.org/10.1111/gcb.12406, 2014.
Harms, T. K. and Jones, J. B.: Thaw depth determines reaction and transport
of inorganic nitrogen in valley bottom permafrost soils, Glob. Chang. Biol.,
18, 2958–2968, https://doi.org/10.1111/j.1365-2486.2012.02731.x, 2012.
Harms, T. K. and Ludwig, S. M.: Retention and removal of nitrogen and
phosphorus in saturated soils of Arctic hillslopes, Biogeochemistry, 127,
291–304, https://doi.org/10.1007/s10533-016-0181-0, 2016.
Harms, T. K., Cook, C. L., Wlostowski, A. N., Gooseff, M. N., and Godsey,
S.E.: Spiraling down hillslopes: nutrient uptake from water tracks in a
warming Arctic, Ecosystems, 22, 1546–1560,
https://doi.org/10.1007/s10021-019-00355-z, 2019.
Heikoop, J. M., Throckmorton, H. M., Newman, B. D., Perkins, G. B., Iversen,
C. M., Chowdhury, T. R., Romanovsky, V., Graham, D. E., Norby, R. J.,
Wilson, C. J., and Wullschleger, S. D.: Isotopic identification of soil and
permafrost nitrate sources in an Arctic tundra ecosystem, J. Geophys. Res.-Biogeo., 120, 1000–1017, https://doi.org/10.1002/2014JG002883, 2015.
Helsel, D. R. and Hirsch, R. M.: Statistical methods in water resources:
Techniques of water resources investigations, 04-A3, U.S. Geological Survey,
Reston, VA, USA, 118–122, https://doi.org/10.3133/twri04A3, 2002.
Hiltbrunner, E., Aerts, R., Bühlmann, T., Huss-Danell, K., Magnusson,
B., Myrold, D. D., Reed, S. C., Sigurdsson, B. D., and Körner, C.:
Ecological consequences of the expansion of N2-fixing plants in cold biomes,
Oecologia, 176, 11–24, https://doi.org/10.1007/s00442-014-2991-x, 2014.
Hinzman, L. D., Deal, C. J., McGuire, A. D., Mernild, S. H., Polyakov, I.
V., and Walsh, J. E.: Trajectory of the Arctic as an integrated system,
Ecol. Appl., 23, 1837–1868, https://doi.org/10.1890/11-1498.1, 2013.
Hopkins, D. M. and Karlstrom, T. N. V.: Permafrost and groundwater in Alaska,
264-F, US Government Printing Office, United States, Washington D. C.,
122–124, 1955.
Hovelsrud, G. K., Poppel, B., van Oort, B., and Reist, J. D.: Arctic
societies, cultures, and peoples in a changing cryosphere, AMBIO, 40,
100–110, https://doi.org/10.1007/s13280-011-0219-4, 2011.
Hurd, T. M. and Raynal, D. J.: Comparison of nitrogen solute concentrations
within alder (Alnus incana ssp. rugosa) and non-alder dominated wetlands,
Hydrol. Process., 18, 2681–2697, https://doi.org/10.1002/hyp.5575, 2004.
Iversen, C., Breen, A., Salmon, V., Vander Stel, H., and Wullschleger, S.
D.: NGEE Arctic Plant Traits: Vegetation plot locations, ecotypes, and
photos, Kougarok Road mile marker 64, Seward Peninsula, Alaska, 2016, Next
Generation Ecosystem Experiments Arctic [data set],
https://doi.org/10.5440/1346196, 2016.
Jakobsen, R. and Postma, D.: Redox zoning, rates of sulfate reduction and
interactions with Fe-reduction and methanogenesis in a shallow sandy
aquifer, Rømø, Denmark, Geochim. Cosmochim. Ac., 63, 137–151,
https://doi.org/10.1016/S0016-7037(98)00272-5, 1999.
Ju, J. and Masek, J. G.: The vegetation greenness trend in Canada and US
Alaska from 1984–2012 Landsat data, Remote Sens. Environ., 176, 1–16,
https://doi.org/10.1016/j.rse.2016.01.001, 2016.
Keuper, F., Dorrepaal, E., van Bodegom, P. M., van Logtestijn, R.,
Venhuizen, G., van Hal, J., and Aerts, R.: Experimentally increased nutrient
availability at the permafrost thaw front selectively enhances biomass
production of deep-rooting subarctic peatland species, Glob. Change Biol.,
23, 4257–4266, https://doi.org/10.1111/gcb.13804, 2017.
Koch, J. C., Runkel, R. L., Striegl, R., and McKnight, D. M.: Hydrologic
controls on the transport and cycling of carbon and nitrogen in a boreal
catchment underlain by continuous permafrost, J. Geophys. Res.-Biogeo.,
118, 698–712, https://doi.org/10.1002/jgrg.20058, 2013.
Martin, P. D., Jenkins, J. L., Adams, F. J., Torre, M., Matz, A. C., Payer,
D. C., Reynolds, P. E., Tidwell, A. C., and Zelenak, J. R.: Wildlife
response to environmental Arctic change: Predicting Future Habitats of
Arctic Alaska, report from: The Wildlife Response to Environmental Arctic
Change (WildREACH): Predicting future habitats of Arctic Alaska workshop,
Fairbanks, AK, USA, 17–18 November 2008.
McCaully, R., Arendt, C., Newman, B., and Heikoop, J.: Sources and Variability of Nitrate on an Alaskan Hillslope Dominated by Alder Shrubs, Kougarok, Alaska, 2017 and 2018, Next Generation Ecosystem Experiments Arctic Data Collection, Oak Ridge National Laboratory, U.S. Department of Energy, Oak Ridge, Tennessee, USA [data set], https://doi.org/10.5440/1544760, 2022.
McClelland, J. W., Stieglitz, M., Pan, F., Holmes, R. M., and Peterson, B.
J.: Recent changes in nitrate and dissolved organic carbon export from the
upper Kuparuk River, North Slope, Alaska: N and C export from the Kuparuk
River, J. Geophys. Res.-Biogeo., 112, G4,
https://doi.org/10.1029/2006JG000371, 2007.
Mitchell, J. S. and Ruess, R. W.: N2 fixing alder (Alnus viridis spp. fruticosa) effects on soil
properties across a secondary successional chronosequence in interior
Alaska, Biogeochemistry, 95, 215–229,
https://doi.org/10.1007/s10533-009-9332-x, 2009.
Moatar, F., Abbot, B. W., Minaudo, C., Curie, F., and Pinay, G.: Elemental
properties, hydrology, and biology interact to shape concentration-discharge
curves for carbon, nutrients, sediment, and major ions, Water Resour. Res.,
53, 1270–1287, https://doi.org/10.1002/2016WR019635, 2017.
Myers-Smith, I. H., Forbes, B. C., Wilmking, M., Hallinger, M., Lantz, T.,
Blok, D., Tape, K. D., Macias-Fauria, M., Sass-Klaassen, U., and
Lévesque, E.: Shrub expansion in tundra ecosystems: dynamics, impacts
and research priorities, Environ. Res. Lett., 6, 045509,
https://doi.org/10.1088/1748-9326/6/4/045509, 2011.
Myers-Smith, I. H., Elmendorf, S. C., Beck, P. S. A., Wilmking, M.,
Hallinger, M., Blok, D, Tape, K. D., Rayback, S. A., Macias-Fauria, M.,
Forbes, B. C., Speed, J. D. M., Boulanger-Lapointe, N., Rixen, C.,
Lévesque, E., Schmidt, N. M., Baittinger, C., Trant, A. J., Hermanutz,
L., Collier, L. S., Dawes, M. A., Lantz, T. C., Weijers, S., Jørgensen,
R. H., Buchwal, A., Buras, A., Naito, A. T., Ravolainen, V.,
Schaepman-Strub, G., Wheeler, J. A., Wipf, S., Guay, K. C., Hik, D. S., and
Vellend, M.: Climate sensitivity of shrub growth across the tundra biome,
Nat. Clim. Chang., 5, 887–891, https://doi.org/10.1038/nclimate2697, 2015.
O'Donnell, J. A. and Jones, J. B.: Nitrogen retention in the riparian zone
of catchments underlain by discontinuous permafrost, Freshw. Biol., 51,
854–864, https://doi.org/10.1111/j.1365-2427.2006.01535.x, 2006.
Ogawa, A., Shibata, H., Suzuki, K., Mitchell, M. J., and Ikegami, Y.:
Relationship of topography to surface water chemistry with particular focus
on nitrogen and organic carbon solutes within a forested watershed in
Hokkaido, Japan, Hydrol. Process., 20, 251–265,
https://doi.org/10.1002/hyp.5901, 2006.
Racine, C. H.: Flora and vegetation: Biological Survey of the Proposed Kobuk
Valley National Monument, Final Report, edited by: Melchior, H. R., Fairbanks, AK,
Alaska Cooperative Park Studies Unit, Biology and Resource Management
Program, University of Alaska, 39–139, 1976.
Racine, C. H. and Anderson, J. H. Flora and vegetation of the Chukchi-Imuruk
area Biological Survey of the Bering Land Bridge National Monument, Revised
Final Report, edited by: Melchior, H. R., Fairbanks, AK: Alaska Cooperative Park
Studies Unit, Biology and Resources Management Program, University of
Alaska, 38–113, 1979.
Ramm, E., Liu, C., Wang, X., Yue, H., Zhang, W., Pan, Y., Schloter, M.,
Gschwendtner, S., Mueller, C. W., Hu, B., Rennenberg, H., and Dannenmann,
M.: The forgotten nutrient - The role of nitrogen in permafrost soils of
Northern China, Adv. Atmos. Sci., 37, 793–799,
https://doi.org/10.1007/s00376-020-0027-5, 2020.
Rasmussen, L. H., Ambus, P., Zhang, W., Jansson, P. E., Michelsen, A., and Elberling, B.: Slope hydrology and permafrost: The effect of snowmelt N transport on downslope ecosystem, EGU General Assembly 2020, Online, 4–8 May 2020, EGU2020-2927, https://doi.org/10.5194/egusphere-egu2020-2927, 2020.
Rasmussen, L. H., Zhang, W., Ambus, P., Michelsen, A., Jansson, P.-E.,
Kitzler, B., and Elberling, B.: Nitrogen transport in a tundra landscape:
the effects of early and late growing season lateral N inputs on arctic soil
and plant N pools and N2O fluxes, Biogeochem., 157, 69–84,
https://doi.org/10.1007/s10533-021-00855-y, 2022.
Rhoades, C., Óskarsson, H., Binkley, D., and Stottlemyer, R.: Alder
(Alnus crispa) effects on soils in ecosystems of the Agashashok River
valley, northwest Alaska, Ecoscience, 8, 89–95,
https://doi.org/10.1080/11956860.2001.11682634, 2001.
Romanovsky, V. E. and Osterkamp, T. E.: Effects of unfrozen water on heat
and mass transport processes in the active layer and permafrost, Permafrost
Periglac., 11, 219–239,
https://doi.org/10.1002/1099-1530(200007/09)11:3<219::AID-PPP352>3.0.CO;2-7, 2000.
Roy, S., Khasa, D. P., and Greer, C. W.: Combining alders, frankiae, and
mycorrhizae for the revegetation and remediation of contaminated ecosystems,
Can. J. Bot., 85, 237–251, https://doi.org/10.1139/B07-017, 2007.
Salmon, V. G., Soucy, P., Mauritz, M., Celis, G., Natali, S. M., Mack, M.
C., and Schuur, E. A. G.: Nitrogen availability increases in a tundra
ecosystem during five years of experimental permafrost thaw, Glob. Chang.
Biol., 22, 1927–1941, https://doi.org/10.1111/gcb.13204, 2016.
Salmon, V. G., Breen, A. L., Kumar, J., Lara, M. J., Thornton, P. E.,
Wullschleger, S. D., and Iversen, C. M.: Alder distribution and expansion
across a tundra hillslope: Implications for local N cycling, Front. Plant
Sci., 10, 1099, https://doi.org/10.3389/fpls.2019.01099, 2019a.
Salmon, V. G., Iversen, C. M., Breen, A. L., Vander Stel, H., and Childs,
J.: NGEE Arctic Plant Traits: Plant Biomass and Traits, Kougarok Road Mile
Marker 64, Seward Peninsula, Alaska, beginning 2016, Next Generation
Ecosystem Experiments Arctic [data set], https://doi.org/10.5440/1346199,
2019b.
Schuur, E. A. G., McGuire, A. D., Schädel, C., Grosse, G., Harden, J.
W., Hayes, D. J., Hugelius, G., Koven, C. D., Kuhry, P., Lawrence, D. M.,
Natali, S. M., Olefeldt, D., Romanovsky, V. E., Schaefer, K., Turetsky, M.
R., Treat, C. C., and Vonk, J. E.: Climate change and the permafrost carbon
feedback, Nature, 520, 171–179, https://doi.org/10.1038/nature14338, 2015.
Seeberg-Elverfeldt, J., Schlüter, M., Feseker, T., and Kölling, M.:
Rhizon sampling of porewaters near the sediment-water interface of aquatic
systems, Limnol. Oceanogr. Methods, 3, 361–371,
https://doi.org/10.4319/lom.2005.3.361, 2005.
Shaftel, R. S., King, R. S., and Back, J. A.: Alder cover drives nitrogen
availability in Kenai lowland headwater streams, Alaska, Biogeochemistry,
107, 135–148, https://doi.org/10.1007/s10533-010-9541-3, 2012.
Sharkhuu, N. and Sharkhuu, A.: Effects of climate warming and vegetation
cover on permafrost of Mongolia, in: Eurasian Steppes. Ecological Problems
and Livelihoods in a Changing World, edited by: Werger, M. J. A. and van
Staalduinen, M. A., Springer Netherlands, Heidelberg, Germany, 445–472,
https://doi.org/10.1007/978-94-007-3886-7_17, 2012.
Shaver, G. R. and Chapin, F. S.: Response to fertilization by various plant
growth forms in an Alaskan tundra: Nutrient accumulation and growth,
Ecology, 61, 662–675, https://doi.org/10.2307/1937432, 1980.
Stookey, L. L.: Ferrozine-A new pectrophotometric reagent for iron, Anal.
Chem., 42, 779–781, https://doi.org/10.1021/ac60289a016, 1970.
Street, L. E., Burns, N. R., and Woodin, S. J.: Slow recovery of High Arctic
heath communities from nitrogen enrichment, New Phytol., 206, 682–695,
https://doi.org/10.1111/nph.13265, 2015.
Sturm, M., Racine, C., and Tape, K.: Increasing shrub abundance in the
Arctic, Nature, 411, 546–547, https://doi.org/10.1038/35079180, 2001.
Tape, K. D., Sturm, M., and Racine, C.: The evidence for shrub expansion in
Northern Alaska and the Pan-Arctic, Glob. Chang. Biol., 12, 686–702,
https://doi.org/10.1111/j.1365-2486.2006.01128.x, 2006.
Tape, K. D., Hallinger, M., Welker, J. M., and Ruess, R. W.: Landscape
heterogeneity of shrub expansion in Arctic Alaska, Ecosystems, 15, 711–724,
https://doi.org/10.1007/s10021-012-9540-4, 2012.
Throckmorton, H. M., Heikoop, J. M., Newman, B. D., Altmann, G. L., Conrad,
M. S., Muss, J. D., Perkins, G. B., Smith, L. J., Torn, M. S., Wullschleger,
S. D., and Wilson, C. J.: Pathways and transformations of dissolved methane
and dissolved inorganic carbon in Arctic tundra watersheds: Evidence from
analysis of stable isotopes, Global Biogeochem. Cycles, 29, 1893–1910,
https://doi.org/10.1002/2014GB005044, 2015.
Till, A. B., Dumoulin, J. A., Werdon, M. B., and Bleick, H. A.: Bedrock
geologic map of the Seward Peninsula, Alaska, and accompanying conodont
data, USGS Scientific Investigations, Map 3131, 75 pp., 2011.
Vink, S., Ford, P. W., Bormans, M., Kelly, C., and Turley, C.: Contrasting
nutrient exports from a forested and an agricultural catchment in
south-eastern Australia, Biogeochemistry, 84, 247–264,
https://doi.org/10.1007/s10533-007-9113-3, 2007.
Vitousek, P. M., Aber, J. D., Howarth, R. W., Likens, G. E., Matson, P. A.,
Schindler, D. W., Schlesinger, W. H., and Tilman, D. G.: Human alteration of
the global nitrogen cycle: Sources and consequences, Ecol. Appl., 7,
737–750, https://doi.org/10.1890/1051-0761(1997)007[0737:HAOTGN]2.0.CO;2,
1997.
Walvoord, M. A. and Kurylyk, B. L.: Hydrologic impacts of thawing
permafrost – A review, Vadose Zone J., 15, 1–20,
https://doi.org/10.2136/vzj2016.01.0010, 2016.
Weintraub, M. N. and Schimel, J. P.: Interactions between carbon and
nitrogen mineralization and soil organic matter chemistry in Arctic tundra
soils, Ecosystems, 6, 129–143, https://doi.org/10.1007/s10021-002-0124-6,
2003.
Weintraub, M. N. and Schimel, J. P.: Nitrogen cycling and the spread of
shrubs control changes in the carbon balance of Arctic tundra ecosystems,
BioScience, 55, 408–415,
https://doi.org/10.1641/0006-3568(2005)055[0408:NCATSO]2.0.CO;2, 2005.
Western Regional Climate Center: RAWS USA Climate Archive, https://raws.dri.edu/cgi-bin/rawMAIN.pl?akAQTZ (last access: 3 May 2021), 2017.
Whigham, D. F., Walker, C. M., Maurer, J., King, R. S., Hauser, W., Baird,
S., Keuskamp, J. A., and Neale, P. J.: Watershed influences on the structure
and function of riparian wetlands associated with headwater streams – Kenai
Peninsula, Alaska, Sci. Total Environ., 599, 124–134,
https://doi.org/10.1016/j.scitotenv.2017.03.290, 2017.
Wullschleger, S. D., Epstein, H. E., Box, E. O., Euskirchen, E. S., Goswami,
S., Iversen, C. M., Kattge, J., Norby, R. J., van Bodegom, P. M., and Xu,
Z.: Plant functional types in Earth system models: past experiences and
future directions for application of dynamic vegetation models in
high-latitude ecosystems, Ann. Bot., 114, 1–16,
https://doi.org/10.1093/aob/mcu077, 2014.
Yamashita, N., Ohta, S., Sase, H., Luangjame, J., Visaratana, T.,
Kievuttinon, B., and Kanzaki, M.: Seasonal and spatial variation of nitrogen
dynamics in the litter and surface soil layers on a tropical dry evergreen
forest slope, For. Ecol. Manage., 259, 1502–1512,
https://doi.org/10.1016/j.foreco.2010.01.026, 2010.
Yano, Y., Shaver, G. R., Giblin, A. E., Rastetter, E. B., and Nadelhoffer,
K. J.: Nitrogen dynamics in a small Arctic watershed: retention and downhill
movement of 15N, Ecol. Monogr., 80, 331–351, https://doi.org/10.1890/08-0773.1,
2010.
Short summary
Degrading permafrost and shrub expansion are critically important to tundra biogeochemistry. We observed significant variability in soil pore water NO3-N in an alder-dominated permafrost hillslope in Alaska. Proximity to alder shrubs and the presence or absence of topographic gradients and precipitation events strongly influence NO3-N availability and mobility. The highly dynamic nature of labile N on small spatiotemporal scales has implications for nutrient responses to a warming Arctic.
Degrading permafrost and shrub expansion are critically important to tundra biogeochemistry. We...
