@article{RamachandranRupakhetiLawrence2020,
  author    = {Ramachandran, Srikanthan and Rupakheti, Maheswar and Lawrence, Mark},
  title     = {Black carbon dominates the aerosol absorption over the Indo-Gangetic Plain and the Himalayan foothills},
  series = {Environment international : a journal of science, technology, health, monitoring and policy},
  volume    = {142},
  journal   = {Environment international : a journal of science, technology, health, monitoring and policy},
  publisher = {Elsevier},
  address   = {Oxford},
  issn      = {0160-4120},
  doi       = {10.1016/j.envint.2020.105814},
  pages     = {12},
  year      = {2020},
  abstract  = {This study, based on new and high quality in situ observations, quantifies for the first time, the individual contributions of light-absorbing aerosols (black carbon (BC), brown carbon (BrC) and dust) to aerosol absorption over the Indo-Gangetic Plain (IGP) and the Himalayan foothill region, a relatively poorly studied region with several sensitive ecosystems of global importance, as well as highly vulnerable populations. The annual and seasonal average single scattering albedo (SSA) over Kathmandu is the lowest of all the locations. The SSA over Kathmandu is < 0.89 during all seasons, which confirms the dominance of light-absorbing carbonaceous aerosols from local and regional sources over Kathmandu. It is observed here that the SSA decreases with increasing elevation, confirming the dominance of light absorbing carbonaceous aerosols at higher elevations. In contrast, the SSA over the IGP does not exhibit a pronounced spatial variation. BC dominates (>= 75\%) the aerosol absorption over the IGP and the Himalayan foothills throughout the year. Higher BC concentration at elevated locations in the Himalayas leads to lower SSA at elevated locations in the Himalayas. The contribution of dust to aerosol absorption is higher throughout the year over the IGP than over the Himalayan foothills. The aerosol absorption over South Asia is very high, exceeding available observations over East Asia, and also exceeds previous model estimates. This quantification will be valuable as observational constraints to help improve regional simulations of climate change, impacts on the glaciers and the hydrological cycle, and will help to direct the focus towards BC as the main contributor to aerosol-induced warming in the region.},
  language  = {en}
}
@article{MorenoCurtidorAnnunziataGuptaetal.2020,
  author    = {Moreno Curtidor, Catalina and Annunziata, Maria Grazia and Gupta, Saurabh and Apelt, Federico and Richard, Sarah Isabel and Kragler, Friedrich and M{\"u}ller-R{\"o}ber, Bernd and Olas, Justyna Jadwiga},
  title     = {Physiological profiling of embryos and dormant seeds in two Arabidopsis accessions reveals a metabolic switch in carbon reserve accumulation},
  series = {Frontiers in plant science},
  volume    = {11},
  journal   = {Frontiers in plant science},
  publisher = {Frontiers Media},
  address   = {Lausanne},
  issn      = {1664-462X},
  doi       = {10.3389/fpls.2020.588433},
  pages     = {14},
  year      = {2020},
  abstract  = {In flowering plants, sugars act as carbon sources providing energy for developing embryos and seeds. Although most studies focus on carbon metabolism in whole seeds, knowledge about how particular sugars contribute to the developmental transitions during embryogenesis is scarce. To develop a quantitative understanding of how carbon composition changes during embryo development, and to determine how sugar status contributes to final seed or embryo size, we performed metabolic profiling of hand-dissected embryos at late torpedo and mature stages, and dormant seeds, in two Arabidopsis thaliana accessions with medium [Columbia-0 (Col-0)] and large [Burren-0 (Bur-0)] seed sizes, respectively. Our results show that, in both accessions, metabolite profiles of embryos largely differ from those of dormant seeds. We found that developmental transitions from torpedo to mature embryos, and further to dormant seeds, are associated with major metabolic switches in carbon reserve accumulation. While glucose, sucrose, and starch predominantly accumulated during seed dormancy, fructose levels were strongly elevated in mature embryos. Interestingly, Bur-0 seeds contain larger mature embryos than Col-0 seeds. Fructose and starch were accumulated to significantly higher levels in mature Bur-0 than Col-0 embryos, suggesting that they contribute to the enlarged mature Bur-0 embryos. Furthermore, we found that Bur-0 embryos accumulated a higher level of sucrose compared to hexose sugars and that changes in sucrose metabolism are mediated by sucrose synthase (SUS), with SUS genes acting non-redundantly, and in a tissue-specific manner to utilize sucrose during late embryogenesis.},
  language  = {en}
}
@article{WolterLantuitWetterichetal.2018,
  author    = {Wolter, Juliane and Lantuit, Hugues and Wetterich, Sebastian and Rethemeyer, Janet and Fritz, Michael},
  title     = {Climatic, geomorphologic and hydrologic perturbations as drivers for mid- to late Holocene development of ice-wedge polygons in the western Canadian Arctic},
  series = {Permafrost and Periglacial Processes},
  volume    = {29},
  journal   = {Permafrost and Periglacial Processes},
  number    = {3},
  publisher = {Wiley},
  address   = {Hoboken},
  issn      = {1045-6740},
  doi       = {10.1002/ppp.1977},
  pages     = {164 -- 181},
  year      = {2018},
  abstract  = {Ice-wedge polygons are widespread periglacial features and influence landscape hydrology and carbon storage. The influence of climate and topography on polygon development is not entirely clear, however, giving high uncertainties to projections of permafrost development. We studied the mid- to late Holocene development of modern ice-wedge polygon sites to explore drivers of change and reasons for long-term stability. We analyzed organic carbon, total nitrogen, stable carbon isotopes, grain size composition and plant macrofossils in six cores from three polygons. We found that ail sites developed from aquatic to wetland conditions. In the mid-Holocene, shallow lakes and partly submerged ice-wedge polygons existed at the studied sites. An erosional hiatus of ca 5000 years followed, and ice-wedge polygons re-initiated within the last millennium. Ice-wedge melt and surface drying during the last century were linked to climatic warming. The influence of climate on ice-wedge polygon development was outweighed by geomorphology during most of the late Holocene. Recent warming, however, caused ice-wedge degradation at all sites. Our study showed that where waterlogged ground was maintained, low-centered polygons persisted for millennia. Ice-wedge melt and increased drainage through geomorphic disturbance, however, triggered conversion into high-centered polygons and may lead to self-enhancing degradation under continued warming.},
  language  = {en}
}
@article{TreatKleinenBroothaertsetal.2019,
  author    = {Treat, Claire C. and Kleinen, Thomas and Broothaerts, Nils and Dalton, April S. and Dommain, Rene and Douglas, Thomas A. and Drexler, Judith Z. and Finkelstein, Sarah A. and Grosse, Guido and Hope, Geoffrey and Hutchings, Jack and Jones, Miriam C. and Kuhry, Peter and Lacourse, Terri and Lahteenoja, Outi and Loisel, Julie and Notebaert, Bastiaan and Payne, Richard J. and Peteet, Dorothy M. and Sannel, A. Britta K. and Stelling, Jonathan M. and Strauss, Jens and Swindles, Graeme T. and Talbot, Julie and Tarnocai, Charles and Verstraeten, Gert and Williams, Christopher J. and Xia, Zhengyu and Yu, Zicheng and Valiranta, Minna and Hattestrand, Martina and Alexanderson, Helena and Brovkin, Victor},
  title     = {Widespread global peatland establishment and persistence over the last 130,000 y},
  series = {Proceedings of the National Academy of Sciences of the United States of America},
  volume    = {116},
  journal   = {Proceedings of the National Academy of Sciences of the United States of America},
  number    = {11},
  publisher = {National Acad. of Sciences},
  address   = {Washington},
  issn      = {0027-8424},
  doi       = {10.1073/pnas.1813305116},
  pages     = {4822 -- 4827},
  year      = {2019},
  abstract  = {Glacial-interglacial variations in CO2 and methane in polar ice cores have been attributed, in part, to changes in global wetland extent, but the wetland distribution before the Last Glacial Maximum (LGM, 21 ka to 18 ka) remains virtually unknown. We present a study of global peatland extent and carbon (C) stocks through the last glacial cycle (130 ka to present) using a newly compiled database of 1,063 detailed stratigraphic records of peat deposits buried by mineral sediments, as well as a global peatland model. Quantitative agreement between modeling and observations shows extensive peat accumulation before the LGM in northern latitudes (> 40 degrees N), particularly during warmer periods including the last interglacial (130 ka to 116 ka, MIS 5e) and the interstadial (57 ka to 29 ka, MIS 3). During cooling periods of glacial advance and permafrost formation, the burial of northern peatlands by glaciers and mineral sediments decreased active peatland extent, thickness, and modeled C stocks by 70 to 90\% from warmer times. Tropical peatland extent and C stocks show little temporal variation throughout the study period. While the increased burial of northern peats was correlated with cooling periods, the burial of tropical peat was predominately driven by changes in sea level and regional hydrology. Peat burial by mineral sediments represents a mechanism for long-term terrestrial C storage in the Earth system. These results show that northern peatlands accumulate significant C stocks during warmer times, indicating their potential for C sequestration during the warming Anthropocene.},
  language  = {en}
}
@article{QuanGoubardBretescheHaerketal.2019,
  author    = {Quan, Ting and Goubard-Bretesche, Nicolas and Haerk, Eneli and Kochovski, Zdravko and Mei, Shilin and Pinna, Nicola and Ballauff, Matthias and Lu, Yan},
  title     = {Highly Dispersible Hexagonal Carbon-MoS2-Carbon Nanoplates with Hollow Sandwich Structures for Supercapacitors},
  series = {Chemistry - a European journal},
  volume    = {25},
  journal   = {Chemistry - a European journal},
  number    = {18},
  publisher = {Wiley-VCH},
  address   = {Weinheim},
  issn      = {0947-6539},
  doi       = {10.1002/chem.201806060},
  pages     = {4757 -- 4766},
  year      = {2019},
  abstract  = {MoS2, a typical layered transition-metal dichalcogenide, is promising as an electrode material in supercapacitors. However, its low electrical conductivity could lead to limited capacitance if applied in electrochemical devices. Herein, a new nanostructure composed of hollow carbon-MoS2-carbon was successfully synthesized through an L-cysteine-assisted hydrothermal method by using gibbsite as a template and polydopamine as a carbon precursor. After calcination and etching of the gibbsite template, uniform hollow platelets, which were made of a sandwich-like assembly of partial graphitic carbon and two-dimensional layered MoS2 flakes, were obtained. The platelets showed excellent dispersibility and stability in water, and good electrical conductivity due to carbon provided by the calcination of polydopamine coatings. The hollow nanoplate morphology of the material provided a high specific surface area of 543 m(2) g(-1), a total pore volume of 0.677 cm(3) g(-1), and fairly small mesopores (approximate to 5.3 nm). The material was applied in a symmetric supercapacitor and exhibited a specific capacitance of 248 F g(-1) (0.12 F cm(-2)) at a constant current density of 0.1 Ag-1; thus suggesting that hollow carbon-MoS2 carbon nanoplates are promising candidate materials for supercapacitors.},
  language  = {en}
}
@article{HeslopWinkelAnthonyetal.2019,
  author    = {Heslop, J. K. and Winkel, Matthias and Anthony, K. M. Walter and Spencer, R. G. M. and Podgorski, D. C. and Zito, P. and Kholodov, A. and Zhang, M. and Liebner, Susanne},
  title     = {Increasing organic carbon biolability with depth in yedoma permafrost},
  series = {Journal of geophysical research : Biogeosciences},
  volume    = {124},
  journal   = {Journal of geophysical research : Biogeosciences},
  number    = {7},
  publisher = {American Geophysical Union},
  address   = {Washington},
  issn      = {2169-8953},
  doi       = {10.1029/2018JG004712},
  pages     = {2021 -- 2038},
  year      = {2019},
  abstract  = {Permafrost thaw subjects previously frozen organic carbon (OC) to microbial decomposition, generating the greenhouse gases (GHG) carbon dioxide (CO2) and methane (CH4) and fueling a positive climate feedback. Over one quarter of permafrost OC is stored in deep, ice-rich Pleistocene-aged yedoma permafrost deposits. We used a combination of anaerobic incubations, microbial sequencing, and ultrahigh-resolution mass spectrometry to show yedoma OC biolability increases with depth along a 12-m yedoma profile. In incubations at 3 degrees C and 13 degrees C, GHG production per unit OC at 12-versus 1.3-m depth was 4.6 and 20.5 times greater, respectively. Bacterial diversity decreased with depth and we detected methanogens at all our sampled depths, suggesting that in situ microbial communities are equipped to metabolize thawed OC into CH4. We concurrently observed an increase in the relative abundance of reduced, saturated OC compounds, which corresponded to high proportions of C mineralization and positively correlated with anaerobic GHG production potentials and higher proportions of OC being mineralized as CH4. Taking into account the higher global warming potential (GWP) of CH4 compared to CO2, thawed yedoma sediments in our study had 2 times higher GWP at 12-versus 9.0-m depth at 3 degrees C and 15 times higher GWP at 13 degrees C. Considering that yedoma is vulnerable to processes that thaw deep OC, our findings imply that it is important to account for this increasing GHG production and GWP with depth to better understand the disproportionate impact of yedoma on the magnitude of the permafrost carbon feedback.},
  language  = {en}
}
@article{PoradaTammRaggioetal.2019,
  author    = {Porada, Philipp and Tamm, Alexandra and Raggio, Jose and Yafang, Cheng and Kleidon, Axel and P{\"o}schl, Ulrich and Weber, Bettina},
  title     = {Global NO and HONO emissions of biological soil crusts estimated by a process-based non-vascular vegetation model},
  series = {Biogeosciences},
  volume    = {16},
  journal   = {Biogeosciences},
  publisher = {Copernicus Publ.},
  address   = {G{\"o}ttingen},
  issn      = {1726-4170},
  doi       = {10.5194/bg-16-2003-2019},
  pages     = {2003 -- 2031},
  year      = {2019},
  abstract  = {The reactive trace gases nitric oxide (NO) and nitrous acid (HONO) are crucial for chemical processes in the atmosphere, including the formation of ozone and OH radicals, oxidation of pollutants, and atmospheric self-cleaning. Recently, empirical studies have shown that biological soil crusts are able to emit large amounts of NO and HONO, and they may therefore play an important role in the global budget of these trace gases. However, the upscaling of local estimates to the global scale is subject to large uncertainties, due to unknown spatial distribution of crust types and their dynamic metabolic activity. Here, we perform an alternative estimate of global NO and HONO emissions by biological soil crusts, using a process-based modelling approach to these organisms, combined with global data sets of climate and land cover. We thereby consider that NO and HONO are emitted in strongly different proportions, depending on the type of crust and their dynamic activity, and we provide a first estimate of the global distribution of four different crust types. Based on this, we estimate global total values of 1.04 Tg yr⁻¹ NO-N and 0.69 Tg yr⁻¹ HONO-N released by biological soil crusts. This corresponds to around 20\% of global emissions of these trace gases from natural ecosystems. Due to the low number of observations on NO and HONO emissions suitable to validate the model, our estimates are still relatively uncertain. However, they are consistent with the amount estimated by the empirical approach, which confirms that biological soil crusts are likely to have a strong impact on global atmospheric chemistry via emissions of NO and HONO.},
  language  = {en}
}