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Contribution of cryptogamic covers to the global cycles of carbon and nitrogen

Wolfgang Elbert, Bettina Weber, Susannah Burrows, Jörg Steinkamp, Burkhard Büdel, Meinrat O. Andreae, Ulrich Pöschl
2012 Nature Geoscience  
Many terrestrial surfaces, including soils, rocks and plants, are covered by photoautotrophic communities, capable of synthesizing their own food from inorganic substances using sunlight as an energy source 1,2 . These communities, known as cryptogamic covers, comprise variable proportions of cyanobacteria, algae, fungi, lichens and bryophytes, and are able to fix carbon dioxide and nitrogen from the atmosphere 3 . However, their influence on global and regional biogeochemical cycling of carbon
more » ... and nitrogen has not yet been assessed. Here, we analyse previously published data on the spatial coverage of cryptogamic communities, and the associated fluxes of carbon and nitrogen, in different types of ecosystem across the globe. We estimate that globally, cryptogamic covers take up around 3.9 Pg carbon per year, corresponding to around 7% of net primary production by terrestrial vegetation. We derive a nitrogen uptake by cryptogamic covers of around 49 Tg per year, suggesting that cryptogamic covers account for nearly half of the biological nitrogen fixation on land. We suggest that nitrogen fixation by cryptogamic covers may be crucial for carbon sequestration by plants. Cryptogamic ground covers (CGC), including biological soil and rock crusts as well as bryophyte and lichen carpets, occur on many terrestrial ground surfaces. Cryptogamic plant covers (CPC), comprising epiphytic and epiphyllic crusts as well as foliose or fruticose lichens and bryophytes, spread over large portions of terrestrial plant surfaces, including stems, branches and leaves of trees and shrubs 1 . As illustrated in Fig. 1 , ground and plant covers occur in a variety of different types, colours and morphologies, and can be found in many different habitats and ecosystems 2 . The photoautotrophic communities can take up atmospheric CO 2 , and many covers containing cyanobacteria can also fix atmospheric N 2 (ref. 3). They produce carbon-and nitrogencontaining organic compounds such as amino acids, carbohydrates and extracellular polymeric substances 4,5 . These products, as well as cryptogamic biomass, are partly consumed by plants, animals and other organisms in the surrounding ecosystem or removed by erosion and runoff 3,6,7 (Fig. 2) . Thus, cryptogamic covers are able to fuel food webs by photosynthesis and nitrogen fixation, which is particularly important in arid regions and other terrestrial environments with low abundance of organic nutrients. The covers can also form biominerals and stabilize ground surfaces through the interaction of minerals, cellular filaments and organic polymers. Accordingly, they act as ecosystem engineers, promoting the rehabilitation of eroded soils in drylands 8, 9 . Their destruction by grazing and trampling enhances erosion and diminishes soil fertility LETTERS NATURE GEOSCIENCE a b c d e f Figure 1 | Cryptogamic covers in different environments. a, Ground cover in the Namib lichen fields (Teloschistes capensis, Xanthoparmelia walteri, Ramalina spp.), Alexander Bay, South Africa. b, Soil crust with cyanobacteria (black) and chlorolichen (Psora decipiens), Nama Karoo semi-desert, Northern Cape, South Africa. c, Rock crust with chlorolichen (Rhizocarpon geographicum aggr.), Sadnig, Eastern Alps, Austria. d, Rock crust with chlorolichens (Chrysothrix chlorina, yellow, Leproloma membranaceum, whitish-grey) and mosses (Dicranum scoparium, Hypnum cupressiforme var. filiforme), Spessart, Germany. e, Plant cover with cyanolichen (Physma byrsaeum) on rainforest tree, northeast Queensland, Australia. f, Plant cover with chlorolichens (Evernia prunastri, Parmelia sulcata, P. subrudecta and others) and a bryophyte (Orthotrichum affine) on maple tree,
doi:10.1038/ngeo1486 fatcat:gjm7qw5ggrhvblz4a37btsskxy

The Impact of Divalent Cations on the Enrichment of Soluble Saccharides in Primary Sea Spray Aerosol

Steven Schill, Susannah Burrows, Elias Hasenecz, Elizabeth Stone, Timothy Bertram
2018 Atmosphere  
compounds that will participate. for the (A) macromolecule-derived mechanism, shown here as the lipid A head group of lipopolysaccharides (LPS), (B) ion-mediated co-adsorption mechanism put forth by Burrows  ...  the sea surface microlayer (SSML) for the (A) macromolecule-derived mechanism, shown here as the lipid A head group of lipopolysaccharides (LPS), (B) ion-mediated co-adsorption mechanism put forth by Burrows  ... 
doi:10.3390/atmos9120476 fatcat:ftf5u6v5lja6xojeqhsa237djq

Impacts of Shifts in Phytoplankton Community on Clouds and Climate via the Sulfur Cycle

Shanlin Wang, Mathew E. Maltrud, Susannah M. Burrows, Scott M. Elliott, Philip Cameron-Smith
2018 Global Biogeochemical Cycles  
Dimethyl sulfide (DMS), primarily produced by marine organisms, contributes significantly to sulfate aerosol loading over the ocean after being oxidized in the atmosphere. In addition to exerting a direct radiative effect, the resulting aerosol particles act as cloud condensation nuclei, modulating cloud properties and extent, with impacts on atmospheric radiative transfer and climate. Thus, changes in pelagic ecosystems, such as phytoplankton physiology and community structure, may influence
more » ... ganosulfur production, and subsequently affect climate via the sulfur cycle. A fully coupled Earth system model, including explicit marine ecosystems and the sulfur cycle, is used here to investigate the impacts of changes associated with individual phytoplankton groups on DMS emissions and climate. Simulations show that changes in phytoplankton community structure, DMS production efficiency, and interactions of multielement biogeochemical cycles can all lead to significant differences in DMS transfer to the atmosphere. Subsequent changes in sulfate aerosol burden, cloud condensation nuclei number, and radiative effect are examined. We find the global annual mean cloud radiative effect shifts up to 0.21 W/m 2 , and the mean surface temperature increases up to 0.1°C due to DMS production changes associated with individual phytoplankton group in simulations with radiative effects at the 2,100 levels under an 8.5 scenario. However, changes in DMS emissions, radiative effect, and surface temperature are more intensive on regional scales. Hence, we speculate that major uncertainties associated with future marine sulfur cycling will involve strong region-to-region climate shifts. Further understanding of marine ecosystems and the relevant phytoplankton-aerosol-climate linkage are needed for improving climate projections.
doi:10.1029/2017gb005862 fatcat:bxei7d2khrervgsg7ggptrxp6q

An Atmospheric Aerosol Short Course for Early Career Scientists

James Mather, Susannah Burrows, Duli Chand, Nancy Hess, Alexander Laskin, Allison McComiskey, Noopur Sharma, John Shilling
2020 Bulletin of The American Meteorological Society - (BAMS)  
Day 5: Aerosol modeling Organized by Susannah Burrows, PNNL; topical presenters: Manabu Shiraiwa, University of California, Irvine; and ManishKumar Shrivastava and Hailong Wang, both at PNNL.  ...  Day 3: Optical and cloud-forming properties of aerosols Organized by Noopur Sharma and Duli Chand, both at PNNL; topical presenters: ManishKumar Shrivastava, Susannah Burrows, and Gourihar Kulkarni, all  ... 
doi:10.1175/bams-d-19-0326.1 fatcat:vsukggg7dra4rn6lhadrsgh3pi

Global modeling of primary biological particle concentrations with the EMAC chemistry-climate model

Meryem Tanarhte, Sara Bacer, Susannah M. Burrows, J. Alex Huffman, Kyle M. Pierce, Andrea Pozzer, Roland Sarda-Estève, Nicole J. Savage, Jos Lelieveld
2018 Atmospheric Chemistry and Physics Discussions  
et al., 2009a; Burrows et al., 2009b) .  ...  PBAP dry and wet depositions are treated as described for 25 other aerosol species (see (Burrows et al., 2009a; Pozzer et al., 2012; Pringle et al., 2010a) and references therein).  ... 
doi:10.5194/acp-2018-361 fatcat:kls4ida4nrcz3johe5slr7speu

Effects of marine organic aerosols as sources of immersion-mode ice-nucleating particles on high-latitude mixed-phase clouds

Xi Zhao, Xiaohong Liu, Susannah M. Burrows, Yang Shi
2021 Atmospheric Chemistry and Physics  
As shown in Table 2 , the hygroscopicity of MOA is set to be 0.1 following Burrows et al. (2014 Burrows et al. ( , 2018 compared to 1.16 for sea salt.  ...  Effects of MOA on clouds as CCN and INPs MOA is emitted into different aerosol modes depending on mixing state of MOA and sea salt (Burrows et al., 2014 (Burrows et al., , 2018 .  ... 
doi:10.5194/acp-21-2305-2021 fatcat:f57rr46oana3rkzr7jkwpszvue

Investigating controls on sea ice algal production using E3SMv1.1-BGC

Nicole Jeffery, Mathew E. Maltrud, Elizabeth C. Hunke, Shanlin Wang, Jon Wolfe, Adrian K. Turner, Susannah M. Burrows, Xiaoying Shi, William H. Lipscomb, Wieslaw Maslowski, Kate V. Calvin
2020 Annals of Glaciology  
Simulation results Burrows and others (2020) present a detailed overview of the E3SMv1.1-BGC pre-industrial control (CNST-forcing) and historical (HIST-forcing; or BDRD-hist in Burrows and others (2020  ...  This paper describes the polar biogeochemistry (BGC) of the Energy Exascale Earth System Model (E3SM) model version E3SMv1.1-BGC ( Burrows and others, 2020) .  ... 
doi:10.1017/aog.2020.7 fatcat:sxdgev2ui5hfpog6bf2q23px64

Primary biological aerosol particles in the atmosphere: a review

VivianeR. Després, J.Alex Huffman, Susannah M. Burrows, Corinna Hoose, AleksandrS. Safatov, Galina Buryak, Janine Fröhlich-Nowoisky, Wolfgang Elbert, MeinratO. Andreae, Ulrich Pöschl, Ruprecht Jaenicke
2012 Tellus: Series B, Chemical and Physical Meteorology  
doi:10.3402/tellusb.v64i0.15598 fatcat:6stepukznvdutjhmdqt3lyqqmq

A numerical framework for simulating the atmospheric variability of supermicron marine biogenic ice nucleating particles

Isabelle Steinke, Paul J. DeMott, Grant B. Deane, Thomas C. J. Hill, Mathew Maltrud, Aishwarya Raman, Susannah M. Burrows
2022 Atmospheric Chemistry and Physics  
are globally the largest source of ice nucleating particles (INPs) of mineral dust origin, there are areas such as the remote ocean regions where local marine sources dominate the emission of INPs (Burrows  ...  Significant advances have been made in developing representations of marine organic INPs appropriate for global climate models (Burrows et al., 2013; Wilson et al., 2015; Huang et al., 2018; McCluskey  ... 
doi:10.5194/acp-22-847-2022 fatcat:smocfuapdvbgzjj267vzkjojay

OCEANFILMS sea-spray organic aerosol emissions – Part 1: implementation and impacts on clouds

Susannah M. Burrows, Richard Easter, Xiaohong Liu, Po-Lun Ma, Hailong Wang, Scott M. Elliott, Balwinder Singh, Kai Zhang, Philip J. Rasch
2018 Atmospheric Chemistry and Physics Discussions  
The evaluation of these simulations by comparison with observations of marine aerosol number, mass, and chemistry is described in detail in a companion paper (Burrows et al., 2017).  ...  Emissions of marine organic aerosol according to OCEANFILMS The OCEANFILMS parameterization, introduced and described in detail in Burrows et al. (2014) , proposes a mechanistic approach for connecting  ... 
doi:10.5194/acp-2018-70 fatcat:zgfh3nhc4nbsbapnr7yh273iwy

Characterizing the Relative Importance Assigned to Physical Variables by Climate Scientists when Assessing Atmospheric Climate Model Fidelity

Susannah M. Burrows, Aritra Dasgupta, Sarah Reehl, Lisa Bramer, Po-Lun Ma, Philip J. Rasch, Yun Qian
2018 Advances in Atmospheric Sciences  
Evaluating a climate model's fidelity (ability to simulate observed climate) is a critical step in establishing confidence in the model's suitability for future climate projections, and in tuning climate model parameters. Model developers use their judgement in determining which trade-offs between different aspects of model fidelity are acceptable. However, little is known about the degree of consensus in these evaluations, and whether experts use the same criteria when different scientific
more » ... ctives are defined. Here, we report on results from a broad community survey studying expert assessments of the relative importance of different output variables when evaluating a global atmospheric model's mean climate. We find that experts adjust their ratings of variable importance in response to the scientific objective, for instance, scientists rate surface wind stress as significantly more important for Southern Ocean climate than for the water cycle in the Asian watershed. There is greater consensus on the importance of certain variables (e.g., shortwave cloud forcing) than others (e.g., aerosol optical depth). We find few differences in expert consensus between respondents with greater or less climate modeling experience, and no statistically significant differences between the responses of climate model developers and users. The concise variable lists and community ratings reported here provide baseline descriptive data on current expert understanding of certain aspects of model evaluation, and can serve as a starting point for further investigation, as well as developing more sophisticated evaluation and scoring criteria with respect to specific scientific objectives.
doi:10.1007/s00376-018-7300-x fatcat:galzweho25cxpezdblf652omu4

Global distribution and surface activity of macromolecules in offline simulations of marine organic chemistry

Oluwaseun O. Ogunro, Susannah M. Burrows, Scott Elliott, Amanda A. Frossard, Forrest Hoffman, Robert T. Letscher, J. Keith Moore, Lynn M. Russell, Shanlin Wang, Oliver W. Wingenter
2015 Biogeochemistry  
What follows is in fact a strong condensation from earlier presentations by our own group Burrows et al. 2014) .  ...  Rising bubbles may acquire additional organic layers during their transition through the ocean-atmosphere interface Burrows et al. 2014) .  ... 
doi:10.1007/s10533-015-0136-x fatcat:ubgjxphrofbofiuddl5vuzxjmq

Bioaerosols in the Earth system: Climate, health, and ecosystem interactions

Janine Fröhlich-Nowoisky, Christopher J. Kampf, Bettina Weber, J. Alex Huffman, Christopher Pöhlker, Meinrat O. Andreae, Naama Lang-Yona, Susannah M. Burrows, Sachin S. Gunthe, Wolfgang Elbert, Hang Su, Peter Hoor (+4 others)
2016 Atmospheric research  
., Brown and Hovmøller, 2002; Burrows et al., 2009a Burrows et al., , 2009b Després et al., 2012; Womack et al., 2010) .  ...  et al., 2013a Burrows et al., , 2014 Wang et al., 2015) .  ... 
doi:10.1016/j.atmosres.2016.07.018 fatcat:fnypo6nv6jgw7ixumgf6ieprw4

Global modeling of fungal spores with the EMAC chemistryclimate model: uncertainties in emission parametrizations and observations

Meryem Tanarhte, Sara Bacer, Susannah M. Burrows, J. Alex Huffman, Kyle M. Pierce, Andrea Pozzer, Roland Sarda-Estève, Nicole J. Savage, Jos Lelieveld
2019 Atmospheric Chemistry and Physics Discussions  
CC BY 4.0 License. been discussed in detail in (Burrows et al., 2009a; Burrows et al., 2013) .  ...  et al., 2009a; Burrows et al., 2009b) .  ... 
doi:10.5194/acp-2019-251 fatcat:4wu5sggwfjahfob4v3go4zbpp4

Fungal spores as a source of sodium salt particles in the Amazon basin

Swarup China, Susannah M. Burrows, Bingbing Wang, Tristan H. Harder, Johannes Weis, Meryem Tanarhte, Luciana V. Rizzo, Joel Brito, Glauber G. Cirino, Po-Lun Ma, John Cliff, Paulo Artaxo (+2 others)
2018 Nature Communications  
In the Amazon basin, particles containing mixed sodium salts are routinely observed and are attributed to marine aerosols transported from the Atlantic Ocean. Using chemical imaging analysis, we show that, during the wet season, fungal spores emitted by the forest biosphere contribute at least 30% (by number) to sodium salt particles in the central Amazon basin. Hydration experiments indicate that sodium content in fungal spores governs their growth factors. Modeling results suggest that fungal
more » ... spores account for~69% (31-95%) of the total sodium mass during the wet season and that their fractional contribution increases during nighttime. Contrary to common assumptions that sodium-containing aerosols originate primarily from marine sources, our results suggest that locally-emitted fungal spores contribute substantially to the number and mass of coarse particles containing sodium. Hence, their role in cloud formation and contribution to salt cycles and the terrestrial ecosystem in the Amazon basin warrant further consideration.
doi:10.1038/s41467-018-07066-4 fatcat:ylf4frvffrhhjcdvpl7xiv3gfm
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