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4. Global dataset of soil organic carbon in tidal marshes

Author

Maxwell, Tania L., Rovai, André S., Adame, Maria Fernanda, Adams, Janine B., Álvarez-Rogel, José, Austin, William E. N., Beasy, Kim, Boscutti, Francesco, Böttcher, Michael E., Bouma, Tjeerd J., Bulmer, Richard H., Burden, Annette, Burke, Shannon A., Camacho, Saritta, Chaudhary, Doongar R., Chmura, Gail L., Copertino, Margareth, Cott, Grace M., Craft, Christopher, Day, John, de los Santos, Carmen B., Denis, Lionel, Ding, Weixin, Ellison, Joanna C., Ewers Lewis, Carolyn J., Giani, Luise, Gispert, Maria, Gontharet, Swanne, González-Pérez, José A., González-Alcaraz, M. Nazaret, Gorham, Connor, Graversen, Anna Elizabeth L., Grey, Anthony, Guerra, Roberta, He, Qiang, Holmquist, James R., Jones, Alice R., Juanes, José A., Kelleher, Brian P., Kohfeld, Karen E., Krause-Jensen, Dorte, Lafratta, Anna, Lavery, Paul S., Laws, Edward A., Leiva-Dueñas, Carmen, Loh, Pei Sun, Lovelock, Catherine E., Lundquist, Carolyn J., Macreadie, Peter I., Mazarrasa, Inés, Megonigal, J. Patrick, Neto, Joao M., Nogueira, Juliana, Osland, Michael J., Pagès, Jordi F., Perera, Nipuni, Pfeiffer, Eva-Maria, Pollmann, Thomas, Raw, Jacqueline L., Recio, María, Ruiz-Fernández, Ana Carolina, Russell, Sophie K., Rybczyk, John M., Sammul, Marek, Sanders, Christian, Santos, Rui, Serrano, Oscar, Siewert, Matthias, Smeaton, Craig, Song, Zhaoliang, Trasar-Cepeda, Carmen, Twilley, Robert R., Van de Broek, Marijn, Vitti, Stefano, Antisari, Livia Vittori, Voltz, Baptiste, Wails, Christy N., Ward, Raymond D., Ward, Melissa, Wolfe, Jaxine, Yang, Renmin, Zubrzycki, Sebastian, Landis, Emily, Smart, Lindsey, Spalding, Mark, and Worthington, Thomas A.

Published
2023
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8. Time to anoxia: Observations and predictions of oxygen drawdown following coastal flood events

Author

Patel, Kaizad F., Rod, Kenton A., Zheng, Jianqiu, Regier, Peter, Machado-Silva, Fausto, Bond-Lamberty, Ben, Chen, Xingyuan, Day, Donnie J., Doro, Kennedy O., Kaufman, Matthew H., Kovach, Matthew, McDowell, Nate, McKever, Sophia A., Megonigal, J. Patrick, Norris, Cooper G., O'Meara, Teri, Peixoto, Roberta B., Rich, Roy, Thornton, Peter, Kemner, Kenneth M., Ward, Nick D., Weintraub, Michael N., and Bailey, Vanessa L.

Published
2024
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18. Decadal biomass increment in early secondary succession woody ecosystems is increased by CO2 enrichment.

Author

Walker, Anthony P, De Kauwe, Martin G, Medlyn, Belinda E, Zaehle, Sönke, Iversen, Colleen M, Asao, Shinichi, Guenet, Bertrand, Harper, Anna, Hickler, Thomas, Hungate, Bruce A, Jain, Atul K, Luo, Yiqi, Lu, Xingjie, Lu, Meng, Luus, Kristina, Megonigal, J Patrick, Oren, Ram, Ryan, Edmund, Shu, Shijie, Talhelm, Alan, Wang, Ying-Ping, Warren, Jeffrey M, Werner, Christian, Xia, Jianyang, Yang, Bai, Zak, Donald R, and Norby, Richard J

Subjects
Trees, Carbon Dioxide, Ecosystem, Biomass, Climate, Photosynthesis, Wood
Abstract

Increasing atmospheric CO2 stimulates photosynthesis which can increase net primary production (NPP), but at longer timescales may not necessarily increase plant biomass. Here we analyse the four decade-long CO2-enrichment experiments in woody ecosystems that measured total NPP and biomass. CO2 enrichment increased biomass increment by 1.05 ± 0.26 kg C m-2 over a full decade, a 29.1 ± 11.7% stimulation of biomass gain in these early-secondary-succession temperate ecosystems. This response is predictable by combining the CO2 response of NPP (0.16 ± 0.03 kg C m-2 y-1) and the CO2-independent, linear slope between biomass increment and cumulative NPP (0.55 ± 0.17). An ensemble of terrestrial ecosystem models fail to predict both terms correctly. Allocation to wood was a driver of across-site, and across-model, response variability and together with CO2-independence of biomass retention highlights the value of understanding drivers of wood allocation under ambient conditions to correctly interpret and predict CO2 responses.

Published
2019

19. Short-Term Groundwater Level Fluctuations Drive Subsurface Redox Variability.

Author

Machado-Silva, Fausto, Weintraub, Michael N., Ward, Nicholas D., Doro, Kennedy O., Regier, Peter J., Ehosioke, Solomon, Thomas, Shan Pushpajom, Peixoto, Roberta B., Sandoval, Leticia, Forbrich, Inke, Kemner, Kenneth M., O'Loughlin, Edward J., Stetten, Lucie, Spanbauer, Trisha, Bridgeman, Thomas B., O'Meara, Teri, Rod, Kenton A., Patel, Kaizad, McDowell, Nate G., and Megonigal, J. Patrick

Published
2024
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21. Hurricane Sandy Effects on Coastal Marsh Elevation Change

Author

Yeates, Alice G., Grace, James B., Olker, Jennifer H., Guntenspergen, Glenn R., Cahoon, Donald R., Adamowicz, Susan, Anisfeld, Shimon C., Barrett, Nels, Benzecry, Alice, Blum, Linda, Christian, Robert R., Grzyb, Joseph, Hartig, Ellen Kracauer, Leo, Kelly Hines, Lerberg, Scott, Lynch, James C., Maher, Nicole, Megonigal, J. Patrick, Reay, William, Siok, Drexel, Starke, Adam, Turner, Vincent, and Warren, Scott

Published
2020

22. Author Correction: Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States.

Author

Holmquist, James R, Windham-Myers, Lisamarie, Bliss, Norman, Crooks, Stephen, Morris, James T, Megonigal, J Patrick, Troxler, Tiffany, Weller, Donald, Callaway, John, Drexler, Judith, Ferner, Matthew C, Gonneea, Meagan E, Kroeger, Kevin D, Schile-Beers, Lisa, Woo, Isa, Buffington, Kevin, Breithaupt, Joshua, Boyd, Brandon M, Brown, Lauren N, Dix, Nicole, Hice, Lyndie, Horton, Benjamin P, MacDonald, Glen M, Moyer, Ryan P, Reay, William, Shaw, Timothy, Smith, Erik, Smoak, Joseph M, Sommerfield, Christopher, Thorne, Karen, Velinsky, David, Watson, Elizabeth, Grimes, Kristin Wilson, and Woodrey, Mark

Abstract

A correction to this article has been published and is linked from the HTML and PDF versions of this paper. The error has not been fixed in the paper.

Published
2018

23. Accuracy and Precision of Tidal Wetland Soil Carbon Mapping in the Conterminous United States.

Author

Holmquist, James R, Windham-Myers, Lisamarie, Bliss, Norman, Crooks, Stephen, Morris, James T, Megonigal, J Patrick, Troxler, Tiffany, Weller, Donald, Callaway, John, Drexler, Judith, Ferner, Matthew C, Gonneea, Meagan E, Kroeger, Kevin D, Schile-Beers, Lisa, Woo, Isa, Buffington, Kevin, Breithaupt, Joshua, Boyd, Brandon M, Brown, Lauren N, Dix, Nicole, Hice, Lyndie, Horton, Benjamin P, MacDonald, Glen M, Moyer, Ryan P, Reay, William, Shaw, Timothy, Smith, Erik, Smoak, Joseph M, Sommerfield, Christopher, Thorne, Karen, Velinsky, David, Watson, Elizabeth, Grimes, Kristin Wilson, and Woodrey, Mark

Abstract

Tidal wetlands produce long-term soil organic carbon (C) stocks. Thus for carbon accounting purposes, we need accurate and precise information on the magnitude and spatial distribution of those stocks. We assembled and analyzed an unprecedented soil core dataset, and tested three strategies for mapping carbon stocks: applying the average value from the synthesis to mapped tidal wetlands, applying models fit using empirical data and applied using soil, vegetation and salinity maps, and relying on independently generated soil carbon maps. Soil carbon stocks were far lower on average and varied less spatially and with depth than stocks calculated from available soils maps. Further, variation in carbon density was not well-predicted based on climate, salinity, vegetation, or soil classes. Instead, the assembled dataset showed that carbon density across the conterminous united states (CONUS) was normally distributed, with a predictable range of observations. We identified the simplest strategy, applying mean carbon density (27.0 kg C m-3), as the best performing strategy, and conservatively estimated that the top meter of CONUS tidal wetland soil contains 0.72 petagrams C. This strategy could provide standardization in CONUS tidal carbon accounting until such a time as modeling and mapping advancements can quantitatively improve accuracy and precision.

Published
2018

30. Sorption of colored vs. noncolored organic matter by tidal marsh soils.

Author

Neale, Patrick J., Megonigal, J. Patrick, Tzortziou, Maria, Canuel, Elizabeth A., Pondell, Christina R., and Morrissette, Hannah

Subjects
SALT marshes, DISSOLVED organic matter, SOIL mineralogy, SORPTION, WETLAND soils, SOILS
Abstract

Tidal marshes are significant sources of colored (or chromophoric) dissolved organic carbon (CDOC) to adjacent waters and, as a result, contribute substantially to their optical complexity and ultimately affect their water quality. Despite this, our mechanistic understanding of the processes that regulate the exchange and transformation of CDOC at the tidal marsh–estuarine interface remains limited. We hypothesized that tidal marsh soils regulate this exchange and transformation subject to soil mineralogy and salinity environment. To test this hypothesis, we generated initial mass sorption isotherms of CDOC and noncolored dissolved organic carbon (NCDOC) using anaerobic batch incubations of Great Dismal Swamp DOC with four tidal wetland soils, representing a range of organic carbon content (1.77 ± 0.12 % to 36.2 ± 2.2 %) and across four salinity treatments (0, 10, 20, and 35). CDOC sorption followed Langmuir isotherms that were similar in shape to those of total DOC, but with greater maximum sorption capacity and lower binding affinity. Like isotherms of total DOC, CDOC maximum sorption capacity increased and binding affinity decreased with greater salinity. Initial natively adsorbed colored organic carbon was low and increased with soil organic content. In contrast, NCDOC desorbed under all conditions with desorption increasing linearly with initial CDOC concentration. This suggests that for our test solutions CDOC displaced NCDOC on tidal marsh soils. Parallel factor analysis of 3-D excitation emission matrices and specific ultraviolet absorbance measurements suggested that CDOC sorption was driven primarily by the exchange of highly aromatic humic-like CDOC. Taken together, these results suggest that tidal marsh soils regulate export and composition of CDOC depending on the complex interplay between soil mineralogy, water salinity, and CDOC vs. NCDOC composition. [ABSTRACT FROM AUTHOR]

Published
2024
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32. The Coastal Carbon Library and Atlas: Open source soil data and tools supporting blue carbon research and policy

Author

Holmquist, James R., primary, Klinges, David, additional, Lonneman, Michael, additional, Wolfe, Jaxine, additional, Boyd, Brandon, additional, Eagle, Meagan, additional, Sanderman, Jonathan, additional, Todd‐Brown, Kathe, additional, Belshe, E. Fay, additional, Brown, Lauren N., additional, Chapman, Samantha, additional, Corstanje, Ron, additional, Janousek, Christopher, additional, Morris, James T., additional, Noe, Gregory, additional, Rovai, André, additional, Spivak, Amanda, additional, Vahsen, Megan, additional, Windham‐Myers, Lisamarie, additional, Kroeger, Kevin, additional, and Megonigal, J. Patrick, additional

Published
2023
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34. Global change effects on plant communities are magnified by time and the number of global change factors imposed

Author

Komatsu, Kimberly J., Avolio, Meghan L., Lemoine, Nathan P., Isbell, Forest, Grman, Emily, Houseman, Gregory R., Koerner, Sally E., Johnson, David S., Wilcox, Kevin R., Alatalo, Juha M., Anderson, John P., Aerts, Rien, Baer, Sara G., Baldwin, Andrew H., Bates, Jonathan, Beierkuhnlein, Carl, Belote, R. Travis, Blair, John, Bloor, Juliette M. G., Bohlen, Patrick J., Bork, Edward W., Boughton, Elizabeth H., Bowman, William D., Britton, Andrea J., Cahill, James F., Chaneton, Enrique, Chiariello, Nona R., Cheng, Jimin, Collins, Scott L., Cornelissen, J. Hans C., Du, Guozhen, Eskelinen, Anu, Firn, Jennifer, Foster, Bryan, Gough, Laura, Gross, Katherine, Hallett, Lauren M., Han, Xingguo, Harmens, Harry, Hovenden, Mark J., Jagerbrand, Annika, Jentsch, Anke, Kern, Christel, Klanderud, Kari, Knapp, Alan K., Kreyling, Juergen, Li, Wei, Luo, Yiqi, McCulley, Rebecca L., McLaren, Jennie R., Megonigal, J. Patrick, Morgan, John W., Onipchenko, Vladimir, Pennings, Steven C., Prevéy, Janet S., Price, Jodi N., Reich, Peter B., Robinson, Clare H., Russell, F. Leland, Sala, Osvaldo E., Seabloom, Eric W., Smith, Melinda D., Soudzilovskaia, Nadejda A., Souza, Lara, Suding, Katherine, Suttle, K. Blake, Svejcar, Tony, Tilman, David, Tognetti, Pedro, Turkington, Roy, White, Shannon, Xu, Zhuwen, Yahdjian, Laura, Yu, Qiang, Zhang, Pengfei, and Zhang, Yunhai

Published
2019

35. Methane emissions from tree stems : a new frontier in the global carbon cycle

Author

Barba, Josep, Bradford, Mark A., Brewer, Paul E., Bruhn, Dan, Covey, Kristofer, van Haren, Joost, Megonigal, J. Patrick, Mikkelsen, Teis Nørgaard, Pangala, Sunitha R., Pihlatie, Mari, Poulter, Ben, Rivas-Ubach, Albert, Schadt, Christopher W., Terazawa, Kazuhiko, Warner, Daniel L., Zhang, Zhen, and Vargas, Rodrigo

Published
2019

39. Effects of Warming and Elevated CO2 on Stomatal Conductance and Chlorophyll Fluorescence of C3 and C4 Coastal Wetland Species.

Author

Sendall, Kerrie M., Muñoz, Cyd M. Meléndez, Ritter, Angela D., Rich, Roy L., Noyce, Genevieve L., and Megonigal, J. Patrick

Abstract

Coastal wetland communities provide valuable ecosystem services such as erosion prevention, soil accretion, and essential habitat for coastal wildlife, but are some of the most vulnerable to the threats of climate change. This work investigates the combined effects of two climate stressors, elevated temperature (ambient, + 1.7 °C, + 3.4 °C, and 5.1 °C) and elevated CO2 (eCO2), on leaf physiological traits of dominant salt marsh plant species. The research took place at the Salt Marsh Accretion Response to Temperature eXperiment (SMARTX) at the Smithsonian Environmental Research Center, which includes two plant communities: a C3 sedge community and a C4 grass community. Here we present data collected over five years on rates of stomatal conductance (gs), quantum efficiency of PSII photochemistry (Fv/Fm), and rates of electron transport (ETRmax). We found that both warming and eCO2 caused declines in all traits, but the warming effects were greater for the C3 sedge. This species showed a strong negative stomatal response to warming in 2017 and 2018 (28% and 17% reduction, respectively in + 5.1 °C). However, in later years the negative response to warming was dampened to < 7%, indicating that S. americanus was able to partially acclimate to the warming over time. In 2022, we found that sedges growing in the combined + 5.1 °C eCO2 plots exhibited more significant declines in gs, Fv/Fm, and ETRmax than in either treatment individually. These results are important for predicting future trends in growth of wetland species, which serve as a large carbon sink that may help mitigate the effects of climate change. [ABSTRACT FROM AUTHOR]

Published
2024
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45. Wetland carbon storage controlled by millennial-scale variation in relative sea-level rise

Author

Rogers, Kerrylee, Kelleway, Jeffrey J., Saintilan, Neil, Megonigal, J. Patrick, Adams, Janine B., Holmquist, James R., and Lu, Meng

Subjects
Soil carbon -- Analysis -- Environmental aspects, Wetlands -- Environmental aspects, Sea level -- Environmental aspects, Carbon sequestration -- Environmental aspects, Salt marshes, Burial, Global temperature changes, Production management, Climate change, Environmental issues, Science and technology, Zoology and wildlife conservation
Abstract

Coastal wetlands (mangrove, tidal marsh and seagrass) sustain the highest rates of carbon sequestration per unit area of all natural systems.sup.1,2, primarily because of their comparatively high productivity and preservation of organic carbon within sedimentary substrates.sup.3. Climate change and associated relative sea-level rise (RSLR) have been proposed to increase the rate of organic-carbon burial in coastal wetlands in the first half of the twenty-first century.sup.4, but these carbon-climate feedback effects have been modelled to diminish over time as wetlands are increasingly submerged and carbon stores become compromised by erosion.sup.4,5. Here we show that tidal marshes on coastlines that experienced rapid RSLR over the past few millennia (in the late Holocene, from about 4,200 years ago to the present) have on average 1.7 to 3.7 times higher soil carbon concentrations within 20 centimetres of the surface than those subject to a long period of sea-level stability. This disparity increases with depth, with soil carbon concentrations reduced by a factor of 4.9 to 9.1 at depths of 50 to 100 centimetres. We analyse the response of a wetland exposed to recent rapid RSLR following subsidence associated with pillar collapse in an underlying mine and demonstrate that the gain in carbon accumulation and elevation is proportional to the accommodation space (that is, the space available for mineral and organic material accumulation) created by RSLR. Our results suggest that coastal wetlands characteristic of tectonically stable coastlines have lower carbon storage owing to a lack of accommodation space and that carbon sequestration increases according to the vertical and lateral accommodation space.sup.6 created by RSLR. Such wetlands will provide long-term mitigating feedback effects that are relevant to global climate-carbon modelling. Wetlands exposed to rapid sea-level rise over the late Holocene contain more soil carbon than those that experienced a long period of sea-level stability., Author(s): Kerrylee Rogers [sup.1] , Jeffrey J. Kelleway [sup.2] , Neil Saintilan [sup.2] , J. Patrick Megonigal [sup.3] , Janine B. Adams [sup.4] , James R. Holmquist [sup.3] , Meng [...]

Published
2019
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