Articles | Volume 2, issue 1
https://doi.org/10.5194/esurf-2-127-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
https://doi.org/10.5194/esurf-2-127-2014
© Author(s) 2014. This work is distributed under
the Creative Commons Attribution 3.0 License.
the Creative Commons Attribution 3.0 License.
Research article
| 
04 Mar 2014
Research article |
| 04 Mar 2014
Preservation of terrestrial organic carbon in marine sediments offshore Taiwan: mountain building and atmospheric carbon dioxide sequestration
S.-J. Kao
Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
R. G. Hilton
Department of Geography, Durham University, Durham, UK
K. Selvaraj
Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
F. Zehetner
Institute of Soil Research, University of Natural Resources and Life Sciences, Vienna, Austria
J.-C. Huang
Department of Geography, National Taiwan University, Taipei, Taiwan
S.-C. Hsu
Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
R. Sparkes
Department of Earth Sciences, University of Cambridge, Cambridge, UK
J. T. Liu
Institute of Marine Geology and Chemistry, National Sun Yat-sen University, Kaohsiung, Taiwan
T.-Y. Lee
Research Center for Environmental Changes, Academia Sinica, Taipei, Taiwan
J.-Y. T. Yang
State Key Laboratory of Marine Environmental Science, Xiamen University, Xiamen, China
Department of Earth Sciences, University of Cambridge, Cambridge, UK
School of Physical Sciences, University of California, Irvine, CA, USA
N. Hovius
Geomorphology, GFZ German Research Centre, Telegrafenberg, Potsdam, Germany
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Amir Kalifi, Philippe Hervé Leloup, Philippe Sorrel, Albert Galy, François Demory, Vincenzo Spina, Bastien Huet, Frédéric Quillévéré, Frédéric Ricciardi, Daniel Michoux, Kilian Lecacheur, Romain Grime, Bernard Pittet, and Jean-Loup Rubino
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In situ oxygen consumption rates were estimated for the first time during destruction of coastal hypoxia as disturbed by a typhoon and its reinstatement in the South China Sea off the Pearl River estuary. The reinstatement of summer hypoxia was rapid with a comparable timescale with that of its initial disturbance from frequent tropical cyclones, which has important implications for better understanding the intermittent nature of coastal hypoxia and its prediction in a changing climate.
Siqi Wu, Moge Du, Xianhui Sean Wan, Corday Selden, Mar Benavides, Sophie Bonnet, Robert Hamersley, Carolin R. Löscher, Margaret R. Mulholland, Xiuli Yan, and Shuh-Ji Kao
Biogeosciences Discuss., https://doi.org/10.5194/bg-2021-104, https://doi.org/10.5194/bg-2021-104, 2021
Preprint withdrawn
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Nitrogen (N2) fixation is one of the most important nutrient sources to the ocean. Here, we report N2 fixation in the deep, dark ocean in the South China Sea via a highly sensitive new method and elaborate controls, showing the overlooked importance of N2 fixation in the deep ocean. By global data compilation, we also provide an easy measured basic parameter to estimate deep N2 fixation. Our study may help to expand the area limit of N2 fixation studies and better constrain global N2 fixation.
Guizhi Wang, Samuel S. P. Shen, Yao Chen, Yan Bai, Huan Qin, Zhixuan Wang, Baoshan Chen, Xianghui Guo, and Minhan Dai
Earth Syst. Sci. Data, 13, 1403–1417, https://doi.org/10.5194/essd-13-1403-2021, https://doi.org/10.5194/essd-13-1403-2021, 2021
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This study reconstructs a complete field of summer sea surface partial pressure of CO2 (pCO2) over the South China Sea (SCS) with a 0.5° resolution in the period of 2000–2017 using the scattered underway pCO2 observations. The spectral optimal gridding method was used in this reconstruction with empirical orthogonal functions computed from remote sensing data. Our reconstructed data show that the rate of sea surface pCO2 increase in the SCS is 2.4 ± 0.8 µatm yr-1 during 2000–2017.
Yanhong Lu, Shunyan Cheung, Ling Chen, Shuh-Ji Kao, Xiaomin Xia, Jianping Gan, Minhan Dai, and Hongbin Liu
Biogeosciences, 17, 6017–6032, https://doi.org/10.5194/bg-17-6017-2020, https://doi.org/10.5194/bg-17-6017-2020, 2020
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Through a comprehensive investigation, we observed differential niche partitioning among diverse ammonia-oxidizing archaea (AOA) sublineages in a typical subtropical estuary. Distinct AOA communities observed at DNA and RNA levels suggested that a strong divergence in ammonia-oxidizing activity among different AOA groups occurs. Our result highlights the importance of identifying major ammonia oxidizers at RNA level in future studies.
Wenfu Tang, Benjamin Gaubert, Louisa Emmons, Yonghoon Choi, Joshua P. DiGangi, Glenn S. Diskin, Xiaomei Xu, Cenlin He, Helen Worden, Simone Tilmes, Rebecca Buchholz, Hannah S. Halliday, and Avelino F. Arellano
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acp-2020-864, https://doi.org/10.5194/acp-2020-864, 2020
Revised manuscript not accepted
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A specific demonstration of the potential use of correlative information from carbon monoxide to refine estimates of regional carbon dioxide emissions from fossil fuel combustion.
Jin-Yu Terence Yang, Kitack Lee, Jia-Zhong Zhang, Ji-Young Moon, Joon-Soo Lee, In-Seong Han, and Eunil Lee
Biogeosciences, 17, 3631–3642, https://doi.org/10.5194/bg-17-3631-2020, https://doi.org/10.5194/bg-17-3631-2020, 2020
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The anthropogenic nitrogen deposition has led to an increase in nitrate relative to phosphate in the upper oligotrophic waters; however, this anthropogenic nitrogen signal is unclear in the North Atlantic. We analyzed datasets from repeated measurements on meridional and zonal transects in the upper North Atlantic between the 1980s and 2010s and found that the anthropogenic nitrogen signal has been found only in the upper western North Atlantic.
Jianjun Zou, Xuefa Shi, Aimei Zhu, Selvaraj Kandasamy, Xun Gong, Lester Lembke-Jene, Min-Te Chen, Yonghua Wu, Shulan Ge, Yanguang Liu, Xinru Xue, Gerrit Lohmann, and Ralf Tiedemann
Clim. Past, 16, 387–407, https://doi.org/10.5194/cp-16-387-2020, https://doi.org/10.5194/cp-16-387-2020, 2020
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Large-scale reorganization of global ocean circulation has been documented in a variety of marine archives, including the enhanced North Pacific Intermediate Water NPIW. Our data support both the model- and data-based ideas that the enhanced NPIW mainly developed during cold spells, while an expansion of oxygen-poor zones occurred at warming intervals (Bölling-Alleröd).
Li Ma, Hua Lin, Xiabing Xie, Minhan Dai, and Yao Zhang
Biogeosciences, 16, 4765–4781, https://doi.org/10.5194/bg-16-4765-2019, https://doi.org/10.5194/bg-16-4765-2019, 2019
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The major microbial process producing N2O in estuarine ecosystems remains controversial. Combining the concentrations and isotopic compositions of N2O, distributions and transcript levels of ammonia-oxidizing bacterial and archaeal amoA and denitrifier nirS genes, and in situ incubation estimates of nitrification rates and N2O production rates, we clarified that ammonia-oxidizing bacteria contributed the major part in N2O production in the upper Pearl River estuary despite their low abundance.
Jun-Yi Lee, Yu-Ting Shih, Chiao-Ying Lan, Tsung-Yu Lee, Tsung-Ren Peng, Cheing-Tung Lee, and Jr-Chuan Huang
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hess-2019-276, https://doi.org/10.5194/hess-2019-276, 2019
Revised manuscript not accepted
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Scientists concern the travel time and the fraction of new water from the sky to the stream to figure out the sources of freshwater and the distribution of contaminants. This study tells a story of water by analyzing the oxygen isotope of rain and stream water. In our sites, a raindrop only needs 2–11 hour to travel to the stream and large storm could exert more and younger new water. The rapid response is likely because of the steep landscape which helps transferring new water to the stream.
Yu-Ting Shih, Pei-Hao Chen, Li-Chin Lee, Chien-Sen Liao, Shih-Hao Jien, Fuh-Kwo Shiah, Tsung-Yu Lee, Thomas Hein, Franz Zehetner, Chung-Te Chang, and Jr-Chuan Huang
Hydrol. Earth Syst. Sci., 22, 6579–6590, https://doi.org/10.5194/hess-22-6579-2018, https://doi.org/10.5194/hess-22-6579-2018, 2018
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DOC and DIC export in Taiwan shows that the annual DOC and DIC fluxes were 2.7–4.8 and 48.4–54.3 ton C km2 yr1, respectively, which were approximately 2 and 20 times higher than the global means of 1.4 and 2.6 ton C km2 yr1, respectively.
Robert B. Sparkes, Melissa Maher, Jerome Blewett, Ayça Doğrul Selver, Örjan Gustafsson, Igor P. Semiletov, and Bart E. van Dongen
The Cryosphere, 12, 3293–3309, https://doi.org/10.5194/tc-12-3293-2018, https://doi.org/10.5194/tc-12-3293-2018, 2018
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Ongoing climate change in the Siberian Arctic region has the potential to release large amounts of carbon, currently stored in permafrost, to the Arctic Shelf. Degradation can release this to the atmosphere as greenhouse gas. We used Raman spectroscopy to analyse a fraction of this carbon, carbonaceous material, a group that includes coal, lignite and graphite. We were able to trace this carbon from the river mouths and coastal erosion sites across the Arctic shelf for hundreds of kilometres.
Yu-Chi Lin, Shih-Chieh Hsu, Chuan-Yao Lin, Shuen-Hsin Lin, Yi-Tang Huang, Yunhua Chang, and Yan-Lin Zhang
Atmos. Chem. Phys., 18, 13865–13879, https://doi.org/10.5194/acp-18-13865-2018, https://doi.org/10.5194/acp-18-13865-2018, 2018
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The Asian continent is a well-known big source of airborne As in the North Pacific region. Previously, high As concentrations over the free troposphere in the region have been observed and considered contributions of industrial emissions, especially of coal-combustion. In our study, we proposed a new concept for a potential source of high As over the subtropical free troposphere, that is, BB activities over southern Asia might be an important source of airborne arsenic in the springtime.
Lei Hou, Xiabing Xie, Xianhui Wan, Shuh-Ji Kao, Nianzhi Jiao, and Yao Zhang
Biogeosciences, 15, 5169–5187, https://doi.org/10.5194/bg-15-5169-2018, https://doi.org/10.5194/bg-15-5169-2018, 2018
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The niche differentiation of ammonia and nitrite oxidizers is controversial because they display disparate patterns in different environments. Combining molecular and nitrification rate analyses, our study clarified that water mass mixing and the substrate availability primarily regulated the niche differentiation of nitrifier populations along a salinity gradient. The nitrifier populations may have specific adaptations to different substrate conditions through their ecological strategies.
Guillaume Soulet, Robert G. Hilton, Mark H. Garnett, Mathieu Dellinger, Thomas Croissant, Mateja Ogrič, and Sébastien Klotz
Biogeosciences, 15, 4087–4102, https://doi.org/10.5194/bg-15-4087-2018, https://doi.org/10.5194/bg-15-4087-2018, 2018
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Oxidative weathering of sedimentary rocks can release carbon dioxide to the atmosphere. Here, we designed a chamber-based method to measure these CO2 emissions directly for the first time. The chamber is drilled in the rock and allows us to collect the CO2 to fingerprint its source using carbon isotopes. We tested our method in Draix (France). The measured CO2 fluxes were substantial, with ~20% originating from oxidation of the rock organic matter and ~80% from dissolution of carbonate minerals.
Li Luo, Shuh-Ji Kao, Hongyan Bao, Huayun Xiao, Hongwei Xiao, Xiaohong Yao, Huiwang Gao, Jiawei Li, and Yangyang Lu
Atmos. Chem. Phys., 18, 6207–6222, https://doi.org/10.5194/acp-18-6207-2018, https://doi.org/10.5194/acp-18-6207-2018, 2018
Chung-Te Chang, Jr-Chuan Huang, Lixin Wang, Yu-Ting Shih, and Teng-Chiu Lin
Biogeosciences, 15, 2379–2391, https://doi.org/10.5194/bg-15-2379-2018, https://doi.org/10.5194/bg-15-2379-2018, 2018
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Our analysis of ion input–output budget illustrates that hydrochemical responses to typhoon storms are distinctly different from those of regular storms. In addition, even mild land use change may have large impacts on nutrient exports/losses. We propose that hydrological models should separate hydrochemical processes into regular and extreme conditions to better capture the whole spectrum of hydrochemical responses to a variety of climate conditions.
Qianqian Liu, Selvaraj Kandasamy, Baozhi Lin, Huawei Wang, and Chen-Tung Arthur Chen
Biogeosciences, 15, 2091–2109, https://doi.org/10.5194/bg-15-2091-2018, https://doi.org/10.5194/bg-15-2091-2018, 2018
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Understanding the global carbon cycling in the marginal seas is crucial to realize the climate–carbon link. Here we characterized the source of suspended particulate matter along the deep chlorophyll maximum layers and found that organic matter in these layers was largely derived from the primary production. Also this layer is insignificantly influenced by the land-derived organic matter. Our results may have a direct implication on the application of isotopic mixing models in marine sediments.
Guizhi Wang, Shuling Wang, Zhangyong Wang, Wenping Jing, Yi Xu, Zhouling Zhang, Ehui Tan, and Minhan Dai
Biogeosciences, 15, 997–1009, https://doi.org/10.5194/bg-15-997-2018, https://doi.org/10.5194/bg-15-997-2018, 2018
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Time-series observations of nutrients and 228Ra, a groundwater discharge tracer, were carried out from spring to neap tide in the Luhuitou fringing reef at Sanya Bay in the South China Sea. Nitrate, phosphate, and silicate in the water column showed greater diurnal variation during the spring tide. Biological processes predominantly controlled the composition of nutrients, but there was less of an impact in the spring tide due to groundwater discharge in this reef system.
Xin Lin, Ruiping Huang, Yan Li, Futian Li, Yaping Wu, David A. Hutchins, Minhan Dai, and Kunshan Gao
Biogeosciences, 15, 551–565, https://doi.org/10.5194/bg-15-551-2018, https://doi.org/10.5194/bg-15-551-2018, 2018
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We examine the effects of elevated CO2 on bacterioplankton community during a mesocosm experiment in subtropical, eutrophic coastal waters in southern China. We found that the elevated CO2 hardly altered the network structure of the bacterioplankton taxa present with high abundance but appeared to reassemble the community network of taxa with low abundance. Results suggest that the bacterioplankton community in this subtropical, high-nutrient coastal environment is insensitive to elevated CO2.
Yangyang Lu, Zuozhu Wen, Dalin Shi, Mingming Chen, Yao Zhang, Sophie Bonnet, Yuhang Li, Jiwei Tian, and Shuh-Ji Kao
Biogeosciences, 15, 1–12, https://doi.org/10.5194/bg-15-1-2018, https://doi.org/10.5194/bg-15-1-2018, 2018
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We investigated the light response of field Trichodesmium N2 fixation and net dissolved nitrogen release behavior. Our results suggest that N2 fixation was a function of light intensity, and the light requirement of Trichodesmium nitrogen fixation was high relative to its photosynthetic light demand. Meanwhile, light is a crucial parameter driving the physiological state of Trichodesmium, which subsequently determined the C / N metabolism and net dissolved nitrogen release.
Jianzhong Su, Minhan Dai, Biyan He, Lifang Wang, Jianping Gan, Xianghui Guo, Huade Zhao, and Fengling Yu
Biogeosciences, 14, 4085–4099, https://doi.org/10.5194/bg-14-4085-2017, https://doi.org/10.5194/bg-14-4085-2017, 2017
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We provide direct and quantitative assessments showing the marine organic matter from eutrophication-induced primary production dominated oxygen consumption in the hypoxic zone, while the terrestrially sourced organic matter also significantly contributed to the formation and maintenance of hypoxia in the lower Pearl River Estuary (PRE) and the adjacent coastal water.
Xiang Gong, Wensheng Jiang, Linhui Wang, Huiwang Gao, Emmanuel Boss, Xiaohong Yao, Shuh-Ji Kao, and Jie Shi
Biogeosciences, 14, 2371–2386, https://doi.org/10.5194/bg-14-2371-2017, https://doi.org/10.5194/bg-14-2371-2017, 2017
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The subsurface chlorophyll maximum layer (SCML) forms near the nitracline. By incorporating a piecewise function for the approximate Gaussian vertical profile of chlorophyll, we derive analytical solutions of a specified nutrient–phytoplankton model. Nitracline depth is deeper than SCML depth, and a thinner SCML corresponds to a steeper nitracline. A higher light attenuation coefficient leads to a shallower but steeper nitracline. Nitracline steepness is independent of surface light intensity.
Tsung-Yu Lee, Li-Chin Lee, Jr-Chuan Huang, Shih-Hao Jien, Thomas Hein, Franz Zehetner, Shuh-Ji Kao, and Fuh-Kwo Shiah
Biogeosciences Discuss., https://doi.org/10.5194/bg-2017-105, https://doi.org/10.5194/bg-2017-105, 2017
Revised manuscript not accepted
Min Nina Xu, Yanhua Wu, Li Wei Zheng, Zhenzhen Zheng, Huade Zhao, Edward A. Laws, and Shuh-Ji Kao
Biogeosciences, 14, 1021–1038, https://doi.org/10.5194/bg-14-1021-2017, https://doi.org/10.5194/bg-14-1021-2017, 2017
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To resolve multiple N transformation rates, we proposed an innovative “isotope matrix method” to simultaneously derive rates for multiple transformations. This method was designed specifically for incubations in the euphotic zone under simulated in situ light conditions and minimized potential biases caused by non-targeted processes. The method facilitates simple post hoc analysis of data and can be used to probe specific effects of environmental factors on the rates of interactive N processes.
Robert B. Sparkes, Ayça Doğrul Selver, Örjan Gustafsson, Igor P. Semiletov, Negar Haghipour, Lukas Wacker, Timothy I. Eglinton, Helen M. Talbot, and Bart E. van Dongen
The Cryosphere, 10, 2485–2500, https://doi.org/10.5194/tc-10-2485-2016, https://doi.org/10.5194/tc-10-2485-2016, 2016
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The permafrost in eastern Siberia contains large amounts of carbon frozen in soils and sediments. Continuing global warming is thawing the permafrost and releasing carbon to the Arctic Ocean. We used pyrolysis-GCMS, a chemical fingerprinting technique, to study the types of carbon being deposited on the continental shelf. We found large amounts of permafrost-sourced carbon being deposited up to 200 km offshore.
Robert Emberson, Niels Hovius, Albert Galy, and Odin Marc
Earth Surf. Dynam., 4, 727–742, https://doi.org/10.5194/esurf-4-727-2016, https://doi.org/10.5194/esurf-4-727-2016, 2016
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Rapid dissolution of bedrock and regolith mobilised by landslides can be an important control on rates of overall chemical weathering in mountain ranges. In this study we analysed a number of landslides and rivers in Taiwan to better understand why this occurs. We find that sulfuric acid resulting from rapid oxidation of highly reactive sulfides in landslide deposits drives the intense weathering and can set catchment-scale solute budgets. This could be a CO2 source in fast-eroding mountains.
Juliane Bischoff, Robert B. Sparkes, Ayça Doğrul Selver, Robert G. M. Spencer, Örjan Gustafsson, Igor P. Semiletov, Oleg V. Dudarev, Dirk Wagner, Elizaveta Rivkina, Bart E. van Dongen, and Helen M. Talbot
Biogeosciences, 13, 4899–4914, https://doi.org/10.5194/bg-13-4899-2016, https://doi.org/10.5194/bg-13-4899-2016, 2016
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The Arctic contains a large pool of carbon that is vulnerable to warming and can be released by rivers and coastal erosion. We study microbial lipids (BHPs) in permafrost and shelf sediments to trace the source, transport and fate of this carbon. BHPs in permafrost deposits are released to the shelf by rivers and coastal erosion, in contrast to other microbial lipids (GDGTs) that are transported by rivers. Several further analyses are needed to understand the complex East Siberian Shelf system.
Xiaobo Jin, Chuanlian Liu, Alex J. Poulton, Minhan Dai, and Xianghui Guo
Biogeosciences, 13, 4843–4861, https://doi.org/10.5194/bg-13-4843-2016, https://doi.org/10.5194/bg-13-4843-2016, 2016
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The vertical structure of the coccolithophore community in the water column was controlled by trophic conditions, which were regulated by mesoscale eddies across the South China Sea basin. Three key species (Emiliania huxleyi, Gephyrocapsa oceanica, Florisphaera profunda) contributed roughly half of the surface ocean coccolith-calcite concentrations. E. huxleyi coccolith length is influenced by light and nutrients through the regulation of growth rates.
Jr-Chuan Huang, Tsung-Yu Lee, Teng-Chiu Lin, Thomas Hein, Li-Chin Lee, Yu-Ting Shih, Shuh-Ji Kao, Fuh-Kwo Shiah, and Neng-Huei Lin
Biogeosciences, 13, 1787–1800, https://doi.org/10.5194/bg-13-1787-2016, https://doi.org/10.5194/bg-13-1787-2016, 2016
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The mean riverine DIN export of 49 watersheds in Taiwan is ∼ 3800 kg N km−2 yr−1, 18 times the global average. The mean riverine DIN export ratio is 0.30–0.51, which is much higher than the average of 0.20–0.25 of large rivers around the world, indicating excessive N input relative to ecosystem retention capacity. The DIN export ratio is positively related to agriculture input, and levels of human disturbance and watersheds with high DIN export ratios are likely at advanced stages of N excess.
Sally Newman, Xiaomei Xu, Kevin R. Gurney, Ying Kuang Hsu, King Fai Li, Xun Jiang, Ralph Keeling, Sha Feng, Darragh O'Keefe, Risa Patarasuk, Kam Weng Wong, Preeti Rao, Marc L. Fischer, and Yuk L. Yung
Atmos. Chem. Phys., 16, 3843–3863, https://doi.org/10.5194/acp-16-3843-2016, https://doi.org/10.5194/acp-16-3843-2016, 2016
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Combining 14C and 13C data from the Los Angeles, CA megacity with background data allows source attribution of CO2 emissions among biosphere, natural gas, and gasoline. The 8-year record of CO2 emissions from fossil fuel burning is consistent with "The Great Recession" of 2008–2010. The long-term trend and source attribution are consistent with government inventories. Seasonal patterns agree with the high-resolution Hestia-LA emission data product, when seasonal wind directions are considered.
Shuh-Ji Kao, Tzu-Ling Chiang, Da-Wei Li, Yi-Chia Hsin, Li-Wei Zheng, Jin-Yu Terence Yang, Shih-Chieh Hsu, Chau-Ron Wu, and Minhan Dai
Clim. Past Discuss., https://doi.org/10.5194/cp-2015-167, https://doi.org/10.5194/cp-2015-167, 2016
Preprint withdrawn
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A 3-D model was run for the South China Sea to explore the effects of sea level drop and monsoon wind intensity on glacial patterns of circulation and ventilation. Winter northeasterly monsoon wind intensity governs the volume transport of Kuroshio intrusion through the Luzon Strait, subsequently, the water exchange rate and the mean residence time of water body of the SCS.
Chuan-Yao Lin, Chiung-Jui Su, Hiroyuki Kusaka, Yuko Akimoto, Yang-Fan Sheng, Jr-Chuan Huang, and Huang-Hsiung Hsu
Atmos. Chem. Phys., 16, 1809–1822, https://doi.org/10.5194/acp-16-1809-2016, https://doi.org/10.5194/acp-16-1809-2016, 2016
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This study evaluated the impact of urbanization over northern Taiwan using the Weather Research and Forecasting (WRF) Model coupled with the Noah land-surface model and a modified urban canopy model (WRF-UCM2D). WRF-UCM2D performed much better than the original UCM coupled with WRF (WRF-UCM) at non-urban stations with a low urban fraction during nighttime. The result of this study has crucial implications for assessing the impacts of urbanization on air quality and regional climate.
K. E. Clark, A. J. West, R. G. Hilton, G. P. Asner, C. A. Quesada, M. R. Silman, S. S. Saatchi, W. Farfan-Rios, R. E. Martin, A. B. Horwath, K. Halladay, M. New, and Y. Malhi
Earth Surf. Dynam., 4, 47–70, https://doi.org/10.5194/esurf-4-47-2016, https://doi.org/10.5194/esurf-4-47-2016, 2016
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The key findings of this paper are that landslides in the eastern Andes of Peru in the Kosñipata Valley rapidly turn over the landscape in ~1320 years, with a rate of 0.076% yr-1. Additionally, landslides were concentrated at lower elevations, due to an intense storm in 2010 accounting for ~1/4 of the total landslide area over the 25-year remote sensing study. Valley-wide carbon stocks were determined, and we estimate that 26 tC km-2 yr-1 of soil and biomass are stripped by landslides.
L. Luo, X. H. Yao, H. W. Gao, S. C. Hsu, J. W. Li, and S. J. Kao
Atmos. Chem. Phys., 16, 325–341, https://doi.org/10.5194/acp-16-325-2016, https://doi.org/10.5194/acp-16-325-2016, 2016
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Concentrations and depositions of various nitrogen species of water-soluble fraction in aerosols were observed during spring over the eastern China seas and northwestern Pacific Ocean. Results revealed nitrogen deposition associated with the sea fog weather was 6 times higher than that of spring supply from the Yangtze River to the ECS shelf. The DON emission had occurred most likely during sea spray. Weather conditions modulate the nitrogen exchange at the ocean-atmosphere boundary.
F. Bouchard, I. Laurion, V. Prėskienis, D. Fortier, X. Xu, and M. J. Whiticar
Biogeosciences, 12, 7279–7298, https://doi.org/10.5194/bg-12-7279-2015, https://doi.org/10.5194/bg-12-7279-2015, 2015
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We report on greenhouse gas (GHG) emissions in permafrost aquatic systems of the Eastern Canadian Arctic. We found strikingly different ages, sources and emission rates depending on aquatic system types. Small and shallow ponds generally emitted young (modern to a few centuries old) GHG, whereas larger and deeper lakes released much older GHG, in particular millennium-old CH4 from lake central areas. To our knowledge, this work is the first to report on GHG age from Canadian Arctic lakes.
T.-C. Lin, P.-J. L. Shaner, L.-J. Wang, Y.-T. Shih, C.-P. Wang, G.-H. Huang, and J.-C. Huang
Hydrol. Earth Syst. Sci., 19, 4493–4504, https://doi.org/10.5194/hess-19-4493-2015, https://doi.org/10.5194/hess-19-4493-2015, 2015
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We summarize our findings as follows: (1) the mountain watersheds are vulnerable to agriculture expansion; (2) proper spatial configuration of agricultural lands in mountain watersheds can mitigate the impact of agriculture on NO3- output by 70%; and (3) the reconstructed element fluxes for the watersheds indicate excessive leaching of N and P, and additional loss of N to the atmosphere via volatilization and denitrification, which likely resulted from excessive fertilizer use.
X.-H. Guo, W.-D. Zhai, M.-H. Dai, C. Zhang, Y. Bai, Y. Xu, Q. Li, and G.-Z. Wang
Biogeosciences, 12, 5495–5514, https://doi.org/10.5194/bg-12-5495-2015, https://doi.org/10.5194/bg-12-5495-2015, 2015
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We report the most comprehensive data set of surface seawater pCO2 and air-sea CO2 fluxes in the East China Sea (ECS) based on 24 surveys conducted in 2006-2011. We categorized the ECS into five different domains characterized by different physics and biogeochemistry to better characterize the seasonality of the pCO2 dynamics and to better constrain the CO2 flux. The annual average CO2 influx into the entire ECS shelf was 6.9+/-4.0 mmol m-2 d-1, about twice the global average in an ocean margin.
R. B. Sparkes, A. Doğrul Selver, J. Bischoff, H. M. Talbot, Ö. Gustafsson, I. P. Semiletov, O. V. Dudarev, and B. E. van Dongen
Biogeosciences, 12, 3753–3768, https://doi.org/10.5194/bg-12-3753-2015, https://doi.org/10.5194/bg-12-3753-2015, 2015
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Siberian permafrost contains large amounts of organic carbon that may be released by climate warming. We collected and analysed samples from the East Siberian Sea, using GDGT biomarkers to trace the sourcing and deposition of organic carbon across the shelf. We show that branched GDGTs may be used to trace river erosion. Results from modelling show that organic carbon on the shelf is a complex process involving river-derived and coastal-derived material as well as marine carbon production.
Y.-C. Lin, C.-J. Tsai, Y.-C. Wu, R. Zhang, K.-H. Chi, Y.-T. Huang, S.-H. Lin, and S.-C. Hsu
Atmos. Chem. Phys., 15, 4117–4130, https://doi.org/10.5194/acp-15-4117-2015, https://doi.org/10.5194/acp-15-4117-2015, 2015
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In this work, size distributions and chemical compositions of 36 PM metals emitted from traffic emissions are explored by tunnel experiments. Potential sources of tunnel PM are also identified. Importantly, fingerprinting ratios of wear debris and automotive catalysts are established. The ratios will be good tools for apportioning PM sources in the polluted urban atmosphere.
Y.-T. Shih, T.-Y. Lee, J.-C. Huang, S.-J. Kao, K.-K. Liu, and F.-J. Chang
Hydrol. Earth Syst. Sci. Discuss., https://doi.org/10.5194/hessd-12-449-2015, https://doi.org/10.5194/hessd-12-449-2015, 2015
Revised manuscript not accepted
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This study combines the observed riverine DIN (dissolved inorganic nitrogen) export and the controlling factors (land-use, population and discharge) to inversely estimate the effective DIN yield factors for individual land-use and per capita loading. Those estimated DIN yield factors can extrapolate all possible combinations of land-use, discharge, and population density, demonstrating the capability for scenario assessment.
S.-J. Kao, B.-Y. Wang, L.-W. Zheng, K. Selvaraj, S.-C. Hsu, X. H. Sean Wan, M. Xu, and C.-T. Arthur Chen
Biogeosciences, 12, 1–14, https://doi.org/10.5194/bg-12-1-2015, https://doi.org/10.5194/bg-12-1-2015, 2015
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This paper presents a new sedimentary nitrogen isotope record (d15N) of a sediment core from the southeastern Arabian Sea (AS). By compiling the published nitrogen isotope data in the AS, we obtain geographically distinctive bottom-depth effects for the northern and southern AS since 35ka. After eliminating the bottom-depth bias, we observe opposite d15N trends in the Holocene between these two areas, reflecting a special coupling of denitrification to the north and N2-fixation to the south.
K. E. Clark, M. A. Torres, A. J. West, R. G. Hilton, M. New, A. B. Horwath, J. B. Fisher, J. M. Rapp, A. Robles Caceres, and Y. Malhi
Hydrol. Earth Syst. Sci., 18, 5377–5397, https://doi.org/10.5194/hess-18-5377-2014, https://doi.org/10.5194/hess-18-5377-2014, 2014
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This paper presents measurements of the balance of water inputs and outputs over 1 year for a river basin in the Andes of Peru. Our results show that the annual water budget is balanced within a few percent uncertainty; that is to say, the amount of water entering the basin was the same as the amount leaving, providing important information for understanding the water cycle. We also show that seasonal storage of water is important in sustaining the flow of water during the dry season.
Z. Cao, M. Dai, W. Evans, J. Gan, and R. Feely
Biogeosciences, 11, 6341–6354, https://doi.org/10.5194/bg-11-6341-2014, https://doi.org/10.5194/bg-11-6341-2014, 2014
T.-Y. Lee, Y.-T. Shih, J.-C. Huang, S.-J. Kao, F.-K. Shiah, and K.-K. Liu
Biogeosciences, 11, 5307–5321, https://doi.org/10.5194/bg-11-5307-2014, https://doi.org/10.5194/bg-11-5307-2014, 2014
J. Tao, J. Gao, L. Zhang, R. Zhang, H. Che, Z. Zhang, Z. Lin, J. Jing, J. Cao, and S.-C. Hsu
Atmos. Chem. Phys., 14, 8679–8699, https://doi.org/10.5194/acp-14-8679-2014, https://doi.org/10.5194/acp-14-8679-2014, 2014
S.-C. Hsu, G.-C. Gong, F.-K. Shiah, C.-C. Hung, S.-J. Kao, R. Zhang, W.-N. Chen, C.-C. Chen, C. C.-K. Chou, Y.-C. Lin, F.-J. Lin, and S.-H. Lin
Atmos. Chem. Phys. Discuss., https://doi.org/10.5194/acpd-14-21433-2014, https://doi.org/10.5194/acpd-14-21433-2014, 2014
Revised manuscript has not been submitted
N. Jiao, Y. Zhang, K. Zhou, Q. Li, M. Dai, J. Liu, J. Guo, and B. Huang
Biogeosciences, 11, 2465–2475, https://doi.org/10.5194/bg-11-2465-2014, https://doi.org/10.5194/bg-11-2465-2014, 2014
Y. Zhang, X. Xie, N. Jiao, S. S.-Y. Hsiao, and S.-J. Kao
Biogeosciences, 11, 2131–2145, https://doi.org/10.5194/bg-11-2131-2014, https://doi.org/10.5194/bg-11-2131-2014, 2014
S. S.-Y. Hsiao, T.-C. Hsu, J.-w. Liu, X. Xie, Y. Zhang, J. Lin, H. Wang, J.-Y. T. Yang, S.-C. Hsu, M. Dai, and S.-J. Kao
Biogeosciences, 11, 2083–2098, https://doi.org/10.5194/bg-11-2083-2014, https://doi.org/10.5194/bg-11-2083-2014, 2014
J.-Y. T. Yang, S.-C. Hsu, M. H. Dai, S. S.-Y. Hsiao, and S.-J. Kao
Biogeosciences, 11, 1833–1846, https://doi.org/10.5194/bg-11-1833-2014, https://doi.org/10.5194/bg-11-1833-2014, 2014
Y.-F. Tseng, J. Lin, M. Dai, and S.-J. Kao
Biogeosciences, 11, 409–423, https://doi.org/10.5194/bg-11-409-2014, https://doi.org/10.5194/bg-11-409-2014, 2014
A. Q. Han, M. H. Dai, J. P. Gan, S.-J. Kao, X. Z. Zhao, S. Jan, Q. Li, H. Lin, C.-T. A. Chen, L. Wang, J. Y. Hu, L. F. Wang, and F. Gong
Biogeosciences, 10, 8159–8170, https://doi.org/10.5194/bg-10-8159-2013, https://doi.org/10.5194/bg-10-8159-2013, 2013
T.-C. Hsu and S.-J. Kao
Biogeosciences, 10, 7847–7862, https://doi.org/10.5194/bg-10-7847-2013, https://doi.org/10.5194/bg-10-7847-2013, 2013
W.-D. Zhai, M.-H. Dai, B.-S. Chen, X.-H. Guo, Q. Li, S.-L. Shang, C.-Y. Zhang, W.-J. Cai, and D.-X. Wang
Biogeosciences, 10, 7775–7791, https://doi.org/10.5194/bg-10-7775-2013, https://doi.org/10.5194/bg-10-7775-2013, 2013
K.-K. Liu, L.-W. Wang, M. Dai, C.-M. Tseng, Y. Yang, C.-H. Sui, L. Oey, K.-Y. Tseng, and S.-M. Huang
Biogeosciences, 10, 7449–7462, https://doi.org/10.5194/bg-10-7449-2013, https://doi.org/10.5194/bg-10-7449-2013, 2013
C. Du, Z. Liu, M. Dai, S.-J. Kao, Z. Cao, Y. Zhang, T. Huang, L. Wang, and Y. Li
Biogeosciences, 10, 6419–6432, https://doi.org/10.5194/bg-10-6419-2013, https://doi.org/10.5194/bg-10-6419-2013, 2013
R. Zhang, J. Jing, J. Tao, S.-C. Hsu, G. Wang, J. Cao, C. S. L. Lee, L. Zhu, Z. Chen, Y. Zhao, and Z. Shen
Atmos. Chem. Phys., 13, 7053–7074, https://doi.org/10.5194/acp-13-7053-2013, https://doi.org/10.5194/acp-13-7053-2013, 2013
T.-Y. Lee, J.-C. Huang, S.-J. Kao, and C.-P. Tung
Biogeosciences, 10, 2617–2632, https://doi.org/10.5194/bg-10-2617-2013, https://doi.org/10.5194/bg-10-2617-2013, 2013
R. G. Hilton, A. Galy, A. J. West, N. Hovius, and G. G. Roberts
Biogeosciences, 10, 1693–1705, https://doi.org/10.5194/bg-10-1693-2013, https://doi.org/10.5194/bg-10-1693-2013, 2013
N. N. Chang, J. C. Shiao, G. C. Gong, S. J. Kao, and C. H. Hsieh
Biogeosciences Discuss., https://doi.org/10.5194/bgd-10-1051-2013, https://doi.org/10.5194/bgd-10-1051-2013, 2013
Revised manuscript not accepted
Related subject area
Chemical: Carbon cycling
Sourcing and long-range transport of particulate organic matter in river bedload: Río Bermejo, Argentina
Channel cross-section heterogeneity of particulate organic carbon transport in the Huanghe
Geomorphic regulation of floodplain soil organic carbon concentration in watersheds of the Rocky and Cascade Mountains, USA
Model predictions of long-lived storage of organic carbon in river deposits
Modelling a century of soil redistribution processes and carbon delivery from small watersheds using a multi-class sediment transport model
Sophia Dosch, Niels Hovius, Marisa Repasch, Joel Scheingross, Jens M. Turowski, Stefanie Tofelde, Oliver Rach, and Dirk Sachse
Earth Surf. Dynam., 12, 907–927, https://doi.org/10.5194/esurf-12-907-2024, https://doi.org/10.5194/esurf-12-907-2024, 2024
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The transport of plant debris in rivers is an important part of the global carbon cycle and influences atmospheric carbon levels through time. We sampled plant debris at the bed of a lowland river and determined the sources as it is transported hundreds of kilometers. Plant debris can persist at the riverbed, but mechanical breakdown reduces its amount, and it is only a small fraction compared to the suspended load. This plant debris and transport patterns need further investigation globally.
Yutian Ke, Damien Calmels, Julien Bouchez, Marc Massault, Benjamin Chetelat, Aurélie Noret, Hongming Cai, Jiubin Chen, Jérôme Gaillardet, and Cécile Quantin
Earth Surf. Dynam., 12, 347–365, https://doi.org/10.5194/esurf-12-347-2024, https://doi.org/10.5194/esurf-12-347-2024, 2024
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Through a river cross-section, we show that fluvial organic carbon in the lower Huanghe has clear vertical and lateral heterogeneity in elemental and isotopic signals. Bank erosion supplies terrestrial organic carbon to the fluvial transport. Physical erosion of aged and refractory organic carbon, including radiocarbon-dead organic carbon source from the biosphere, from relatively deep soil horizons of the Chinese Loess Plateau contributes to fluvial particulate organic carbon in the Huanghe.
Daniel N. Scott and Ellen E. Wohl
Earth Surf. Dynam., 6, 1101–1114, https://doi.org/10.5194/esurf-6-1101-2018, https://doi.org/10.5194/esurf-6-1101-2018, 2018
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Mountain rivers play an important role in storing organic carbon (OC) on the landscape. We use field sampling to quantify OC concentrations in floodplain soils of two disparate mountain river basins. We find that local valley geometry and hydrology are dominant controls on OC concentration. This implies that OC concentration cannot be predicted using consistent downstream trends. Instead, geomorphology must be accounted for to understand the spatial distribution of OC in river basins.
Mark A. Torres, Ajay B. Limaye, Vamsi Ganti, Michael P. Lamb, A. Joshua West, and Woodward W. Fischer
Earth Surf. Dynam., 5, 711–730, https://doi.org/10.5194/esurf-5-711-2017, https://doi.org/10.5194/esurf-5-711-2017, 2017
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In this paper, we describe a new model for the storage times of sediments and organic carbon (OC) in river deposits. Comparisons between our model predictions and field data show good agreement, which suggests that our model accurately captures the relevant time and space scales. An implication of our model is that OC is stored in river deposits over geologic timescales and, as a result, we propose that fluvial storage plays a larger role in the carbon cycle than previously recognized.
Florian Wilken, Peter Fiener, and Kristof Van Oost
Earth Surf. Dynam., 5, 113–124, https://doi.org/10.5194/esurf-5-113-2017, https://doi.org/10.5194/esurf-5-113-2017, 2017
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This study presents a model that accounts for preferential erosion and transport of sediment and soil organic carbon in agricultural landscapes. We applied the model to a small catchment in Belgium for a period of 100 years. After a thorough model evaluation, these simulations shows that sediment and carbon export are highly episodic and that the temporal variability is largely influenced by selective erosion and deposition.
