Articles | Volume 11, issue 15
Research article 05 Aug 2011
Research article | 05 Aug 2011
Methane flux, vertical gradient and mixing ratio measurements in a tropical forest
C. A. S. Querino et al.
Related subject area
Subject: Biosphere Interactions | Research Activity: Field Measurements | Altitude Range: Troposphere | Science Focus: Physics (physical properties and processes)Concentrations and biosphere–atmosphere fluxes of inorganic trace gases and associated ionic aerosol counterparts over the Amazon rainforestAboveground biomass in Inner Mongolian temperate grasslands decreases under climate warmingCharacterization of the radiative impact of aerosols on CO2 and energy fluxes in the Amazon deforestation arch using artificial neural networksNew particle formation events observed at the King Sejong Station, Antarctic Peninsula – Part 2: Link with the oceanic biological activitiesVertical observations of the atmospheric boundary layer structure over Beijing urban area during air pollution episodesCharacterisation of short-term extreme methane fluxes related to non-turbulent mixing above an Arctic permafrost ecosystemCharacterization of ozone deposition to a mixed oak–hornbeam forest – flux measurements at five levels above and inside the canopy and their interactions with nitric oxideDirect effect of aerosols on solar radiation and gross primary production in boreal and hemiboreal forestsThe monsoon effect on energy and carbon exchange processes over a highland lake in the southwest of ChinaTurbulent transport of energy across a forest and a semiarid shrublandStudy of the daily and seasonal atmospheric CH4 mixing ratio variability in a rural Spanish region using 222Rn tracerNighttime wind and scalar variability within and above an Amazonian canopyEstimating regional-scale methane flux and budgets using CARVE aircraft measurements over AlaskaCanopy uptake dominates nighttime carbonyl sulfide fluxes in a boreal forestNet ecosystem exchange and energy fluxes measured with the eddy covariance technique in a western Siberian bogBiophysical effects on the interannual variation in carbon dioxide exchange of an alpine meadow on the Tibetan PlateauQuantifying the contribution of land use change to surface temperature in the lower reaches of the Yangtze RiverOverview of mercury dry deposition, litterfall, and throughfall studiesScalar turbulent behavior in the roughness sublayer of an Amazonian forestSurface–atmosphere exchange of ammonia over peatland using QCL-based eddy-covariance measurements and inferential modelingCharacterization of total ecosystem-scale biogenic VOC exchange at a Mediterranean oak–hornbeam forestAre BVOC exchanges in agricultural ecosystems overestimated? Insights from fluxes measured in a maize field over a whole growing seasonStep changes in persistent organic pollutants over the Arctic and their implicationsEstimating surface fluxes using eddy covariance and numerical ogive optimizationNitrous oxide emissions from a commercial cornfield (Zea mays) measured using the eddy covariance techniqueObservations of the scale-dependent turbulence and evaluation of the flux–gradient relationship for sensible heat for a closed Douglas-fir canopy in very weak wind conditionsThe effect of atmospheric aerosol particles and clouds on net ecosystem exchange in the AmazonAcetaldehyde exchange above a managed temperate mountain grasslandSurface response to rain events throughout the West African monsoonThe role of vegetation in the CO2 flux from a tropical urban neighbourhoodAir-surface exchange measurements of gaseous elemental mercury over naturally enriched and background terrestrial landscapes in AustraliaFour-year (2006–2009) eddy covariance measurements of CO2 flux over an urban area in BeijingMomentum and scalar transport within a vegetation canopy following atmospheric stability and seasonal canopy changes: the CHATS experimentCoupling processes and exchange of energy and reactive and non-reactive trace gases at a forest site – results of the EGER experimentAbiotic and biotic control of methanol exchanges in a temperate mixed forestAnalysis of coherent structures and atmosphere-canopy coupling strength during the CABINEX field campaignThe effects of clouds and aerosols on net ecosystem CO2 exchange over semi-arid Loess Plateau of Northwest ChinaSize-dependent aerosol deposition velocities during BEARPEX'07Day-time concentrations of biogenic volatile organic compounds in a boreal forest canopy and their relation to environmental and biological factors
Robbie Ramsay, Chiara F. Di Marco, Matthias Sörgel, Mathew R. Heal, Samara Carbone, Paulo Artaxo, Alessandro C. de Araùjo, Marta Sá, Christopher Pöhlker, Jost Lavric, Meinrat O. Andreae, and Eiko Nemitz
Atmos. Chem. Phys., 20, 15551–15584,Short summary
The Amazon rainforest is a unique
laboratoryto study the processes which govern the exchange of gases and aerosols to and from the atmosphere. This study investigated these processes by measuring the atmospheric concentrations of trace gases and particles at the Amazon Tall Tower Observatory. We found that the long-range transport of pollutants can affect the atmospheric composition above the Amazon rainforest and that the gases ammonia and nitrous acid can be emitted from the rainforest.
Guocheng Wang, Zhongkui Luo, Yao Huang, Wenjuan Sun, Yurong Wei, Xi Deng, Jinhuan Zhu, and Wen Zhang
Atmos. Chem. Phys. Discuss.,
Revised manuscript accepted for ACPShort summary
We combine aboveground biomass (AGB) measurements from six long-term experiments and data synthesized from literatures to explore spatiotemporal changes in AGB in Inner Mongolian grasslands. By adopting a machine learning-based approach, we map annual AGB at the spatial resolution of 1 km and find an overall decline in AGB over the past four decades. Under the ongoing temperature rising, AGB will decrease by 14 %–28 % at the end of this century, compared with the average AGB during 1981–2019.
Renato Kerches Braghiere, Marcia Akemi Yamasoe, Nilton Manuel Évora do Rosário, Humberto Ribeiro da Rocha, José de Souza Nogueira, and Alessandro Carioca de Araújo
Atmos. Chem. Phys., 20, 3439–3458,Short summary
We evaluate how the interaction of smoke with sun light impacts the exchange of energy and mass between vegetation and the atmosphere using a machine learning technique. We found an effect of the smoke on CO2, energy, and water fluxes, linking the effects of smoke with temperature, humidity, and winds. CO2 exchange increased by up to 55 % in the presence of smoke. A decrease of 12 % was observed for a site with simpler vegetation. Energy fluxes were negatively impacted for all study sites.
Eunho Jang, Ki-Tae Park, Young Jun Yoon, Tae-Wook Kim, Sang-Bum Hong, Silvia Becagli, Rita Traversi, Jaeseok Kim, and Yeontae Gim
Atmos. Chem. Phys., 19, 7595–7608,Short summary
We reported long-term observations (from 2009 to 2016) of the nanoparticles measured at the Antarctic Peninsula (62.2° S, 58.8° W), and satellite-derived estimates of the biological characteristics were analyzed to identify the link between new particle formation and marine biota. The key finding from this research is that the formation of nanoparticles was strongly associated not only with the biomass of phytoplankton but, more importantly, also its taxonomic composition in the Antarctic Ocean.
Linlin Wang, Junkai Liu, Zhiqiu Gao, Yubin Li, Meng Huang, Sihui Fan, Xiaoye Zhang, Yuanjian Yang, Shiguang Miao, Han Zou, Yele Sun, Yong Chen, and Ting Yang
Atmos. Chem. Phys., 19, 6949–6967,Short summary
Urban boundary layer (UBL) affects the physical and chemical processes of the pollutants, and UBL structure can also be altered by pollutants. This paper presents the interactions between air pollution and the UBL structure by using the field data mainly collected from a 325 m meteorology tower, as well as from a Doppler wind lidar, during a severe heavy pollution event that occurred during 1–4 December 2016 in Beijing.
Carsten Schaller, Fanny Kittler, Thomas Foken, and Mathias Göckede
Atmos. Chem. Phys., 19, 4041–4059,Short summary
Methane emissions from biogenic sources, e.g. Arctic permafrost ecosystems, are associated with uncertainties due to the high variability of fluxes in both space and time. Besides the traditional eddy covariance method, we evaluated a method based on wavelet analysis, which does not require a stationary time series, to calculate fluxes. The occurrence of extreme methane flux events was strongly correlated with the soil temperature. They were triggered by atmospheric non-turbulent mixing.
Angelo Finco, Mhairi Coyle, Eiko Nemitz, Riccardo Marzuoli, Maria Chiesa, Benjamin Loubet, Silvano Fares, Eugenio Diaz-Pines, Rainer Gasche, and Giacomo Gerosa
Atmos. Chem. Phys., 18, 17945–17961,Short summary
A 1-month field campaign of ozone (O3) flux measurements along a five-level vertical profile of a mature broadleaf forest highlighted that the biosphere–atmosphere exchange of this pollutant is modulated by complex diel dynamics occurring within and below the canopy. The canopy removed nearly 80 % of the O3 deposited to the forest; only a minor part was removed by the soil and the understorey (2 %), while the remaining 18.2 % was removed by chemical reactions with NO mostly emitted from soil.
Ekaterina Ezhova, Ilona Ylivinkka, Joel Kuusk, Kaupo Komsaare, Marko Vana, Alisa Krasnova, Steffen Noe, Mikhail Arshinov, Boris Belan, Sung-Bin Park, Jošt Valentin Lavrič, Martin Heimann, Tuukka Petäjä, Timo Vesala, Ivan Mammarella, Pasi Kolari, Jaana Bäck, Üllar Rannik, Veli-Matti Kerminen, and Markku Kulmala
Atmos. Chem. Phys., 18, 17863–17881,Short summary
Understanding the connections between aerosols, solar radiation and photosynthesis in terrestrial ecosystems is important for estimates of the CO2 balance in the atmosphere. Atmospheric aerosols and clouds influence solar radiation. In this study, we quantify the aerosol effect on solar radiation in boreal forests and study forest ecosystems response to this change in the radiation conditions. The analysis is based on atmospheric observations from several remote stations in Eurasian forests.
Qun Du, Huizhi Liu, Lujun Xu, Yang Liu, and Lei Wang
Atmos. Chem. Phys., 18, 15087–15104,Short summary
Erhai Lake is a subtropical highland shallow lake on the southeast margin of the Tibetan Plateau, which is influenced by both South Asian and East Asian summer monsoons. The substantial difference in atmospheric properties during monsoon and non-monsoon periods has a large effect in regulating turbulent heat and carbon dioxide exchange processes over Erhai Lake. Large difference are found for the factors controlling sensible heat and carbon dioxide flux during monsoon and non-monsoon periods.
Tirtha Banerjee, Peter Brugger, Frederik De Roo, Konstantin Kröniger, Dan Yakir, Eyal Rotenberg, and Matthias Mauder
Atmos. Chem. Phys., 18, 10025–10038,Short summary
We studied the nature of turbulent transport over a well-defined surface heterogeneity (approximate scale 7 km) comprising a shrubland and a forest in the Yatir semiarid area in Israel. Using eddy covariance and Doppler lidar measurements, we studied the variations in the turbulent kinetic energy budget and turbulent fluxes, focusing especially on transport terms. We also confirmed the role of large-scale secondary circulations that transport energy between the shrubland and the forest.
Claudia Grossi, Felix R. Vogel, Roger Curcoll, Alba Àgueda, Arturo Vargas, Xavier Rodó, and Josep-Anton Morguí
Atmos. Chem. Phys., 18, 5847–5860,Short summary
To gain a full picture of the Spanish (and European) GHG balance, understanding of CH4 emissions in different regions is a critical challenge, as is the improvement of bottom-up inventories for all European regions. This study uses, among other elements, GHG, meteorological and 222Rn tracer data from a Spanish region to understand the main causes of temporal variability of GHG mixing ratios. The study can offer new insights into regional emissions by identifying the impacts of changing sources.
Pablo E. S. Oliveira, Otávio C. Acevedo, Matthias Sörgel, Anywhere Tsokankunku, Stefan Wolff, Alessandro C. Araújo, Rodrigo A. F. Souza, Marta O. Sá, Antônio O. Manzi, and Meinrat O. Andreae
Atmos. Chem. Phys., 18, 3083–3099,Short summary
Carbon dioxide and latent heat fluxes within the canopy are dominated by low-frequency (nonturbulent) processes. There is a striking contrast between fully turbulent and intermittent nights, such that turbulent processes dominate the total nighttime exchange during the former, while nonturbulent processes are more relevant in the latter. In very stable nights, during which intermittent exchange prevails, the stable boundary layer may be shallower than the highest observational level at 80 m.
Sean Hartery, Róisín Commane, Jakob Lindaas, Colm Sweeney, John Henderson, Marikate Mountain, Nicholas Steiner, Kyle McDonald, Steven J. Dinardo, Charles E. Miller, Steven C. Wofsy, and Rachel Y.-W. Chang
Atmos. Chem. Phys., 18, 185–202,Short summary
Methane is the second most important greenhouse gas but its emissions from northern regions are still poorly constrained. This study uses aircraft measurements of methane from Alaska to estimate surface emissions. We found that methane emission rates depend on the soil temperature at depths where its production was taking place, and that total emissions were similar between tundra and boreal regions. These results provide a simple way to predict methane emissions in this region.
Linda M. J. Kooijmans, Kadmiel Maseyk, Ulli Seibt, Wu Sun, Timo Vesala, Ivan Mammarella, Pasi Kolari, Juho Aalto, Alessandro Franchin, Roberta Vecchi, Gianluigi Valli, and Huilin Chen
Atmos. Chem. Phys., 17, 11453–11465,Short summary
Carbon cycle studies rely on the accuracy of models to estimate the amount of CO2 being taken up by vegetation. The gas carbonyl sulfide (COS) can serve as a tool to estimate the vegetative CO2 uptake by scaling the ecosystem uptake of COS to that of CO2. Here we investigate the nighttime fluxes of COS. The relationships found in this study will aid in implementing nighttime COS uptake in models, which is key to obtain accurate estimates of vegetative CO2 uptake with the use of COS.
Pavel Alekseychik, Ivan Mammarella, Dmitry Karpov, Sigrid Dengel, Irina Terentieva, Alexander Sabrekov, Mikhail Glagolev, and Elena Lapshina
Atmos. Chem. Phys., 17, 9333–9345,Short summary
West Siberian peatlands occupy a large fraction of land area in the region, and yet little is known about their interaction with the atmosphere. We took the first measurements of CO2 and energy surface balances over a typical bog of West Siberian middle taiga, in the vicinity of the Mukhrino field station (Khanty–Mansiysk). The May–August study in a wet year (2015) revealed a relatively large photosynthetic sink of CO2 that was close to the high end of estimates at bog sites elsewhere.
Lei Wang, Huizhi Liu, Jihua Sun, and Yaping Shao
Atmos. Chem. Phys., 17, 5119–5129,Short summary
This study found that the seasonal variation in CO2 exchange over an alpine meadow on the Tibetan Plateau was primarily affected by the seasonal pattern of air temperature, especially in spring and autumn. The annual net ecosystem exchange decreased with mean annual temperature, and then increased when the gross primary production became saturated. This study contributes to the response of the alpine meadow ecosystem to global warming.
Xueqian Wang, Weidong Guo, Bo Qiu, Ye Liu, Jianning Sun, and Aijun Ding
Atmos. Chem. Phys., 17, 4989–4996,Short summary
Land use or cover change is a fundamental anthropogenic forcing for climate change. Based on field observations, we quantified the contributions of different factors to surface temperature change and deepened the understanding of its mechanisms. We found evaporative cooling plays the most important role in the temperature change, while radiative forcing, which is traditionally emphasized, is not significant. This study provided firsthand evidence to verify the model results in IPCC AR5.
L. Paige Wright, Leiming Zhang, and Frank J. Marsik
Atmos. Chem. Phys., 16, 13399–13416,Short summary
The current knowledge concerning mercury dry deposition is reviewed, including dry deposition algorithms used in chemical transport models and at monitoring sites, measurement methods and studies for quantifying dry deposition of oxidized mercury, and measurement studies of litterfall and throughfall mercury. Over all the regions, dry deposition, estimated as the sum of litterfall and throughfall minus open-field wet deposition, is more dominant than wet deposition for Hg deposition.
Einara Zahn, Nelson L. Dias, Alessandro Araújo, Leonardo D. A. Sá, Matthias Sörgel, Ivonne Trebs, Stefan Wolff, and Antônio Manzi
Atmos. Chem. Phys., 16, 11349–11366,Short summary
Preliminary data from the ATTO project were analyzed to characterize the exchange of heat, water vapor, and CO2 between the Amazon forest and the atmosphere. The forest roughness makes estimation of their fluxes difficult, and even measurements at 42 m above the canopy show a lot of scatter. Still, measurements made around noon showed much better conformity with standard theories for the exchange of these quantities, opening the possibility of good flux estimates when the sun is high.
Undine Zöll, Christian Brümmer, Frederik Schrader, Christof Ammann, Andreas Ibrom, Christophe R. Flechard, David D. Nelson, Mark Zahniser, and Werner L. Kutsch
Atmos. Chem. Phys., 16, 11283–11299,Short summary
Accurate quantification of atmospheric ammonia concentration and exchange fluxes with the land surface has been a major metrological challenge. We demonstrate the applicability of a novel laser device to identify concentration and flux patterns over a peatland ecosystem influenced by nearby agricultural practices. Results help to strengthen air quality monitoring networks, lead to better understanding of ecosystem functionality and improve parameterizations in air chemistry and transport models.
Simon Schallhart, Pekka Rantala, Eiko Nemitz, Ditte Taipale, Ralf Tillmann, Thomas F. Mentel, Benjamin Loubet, Giacomo Gerosa, Angelo Finco, Janne Rinne, and Taina M. Ruuskanen
Atmos. Chem. Phys., 16, 7171–7194,Short summary
We present ecosystem exchange fluxes from a mixed oak–hornbeam forest in the Po Valley, Italy. Detectable fluxes were observed for 29 compounds, dominated by isoprene, which comprised over 60 % of the upward flux. Methanol seemed to be deposited to dew, as the deposition happened in the early morning. We estimated that up to 30 % of the upward flux of methyl vinyl ketone and methacrolein originated from atmospheric oxidation of isoprene.
Aurélie Bachy, Marc Aubinet, Niels Schoon, Crist Amelynck, Bernard Bodson, Christine Moureaux, and Bernard Heinesch
Atmos. Chem. Phys., 16, 5343–5356,Short summary
This research focuses on Biogenic Volatile Organic Compounds (BVOC) exchanges between a maize field and the atmosphere. Indeed, few BVOC studies have already investigated agricultural ecosystems. We found that the maize field emitted mainly methanol, that both soil and plants contributed to the net exchange, that exchanges were lower than in other studies and than considered by models. Our work tends thus to lower the impact of maize on terrestrial BVOC exchanges.
Y. Zhao, T. Huang, L. Wang, H. Gao, and J. Ma
Atmos. Chem. Phys., 15, 3479–3495,Short summary
After several decades of declining persistent organic pollutants in the arctic environment due to their global use restriction, some of these toxic chemicals increased in the mid-2000s and undertook statistically significant step changes which coincided with arctic sea ice melting. Results provide statistical evidence for the releasing of toxic chemicals from their reservoirs in the Arctic due to the rapid change in the arctic environment.
J. Sievers, T. Papakyriakou, S. E. Larsen, M. M. Jammet, S. Rysgaard, M. K. Sejr, and L. L. Sørensen
Atmos. Chem. Phys., 15, 2081–2103,
H. Huang, J. Wang, D. Hui, D. R. Miller, S. Bhattarai, S. Dennis, D. Smart, T. Sammis, and K. C. Reddy
Atmos. Chem. Phys., 14, 12839–12854,Short summary
An EC system was assembled with a sonic anemometer and a new fast-response N2O analyzer and applied in a cornfield during a growing season. This N2O EC system provided reliable N2O flux measurements. The average flux was about 63% higher during the daytime than during the nighttime. Seasonal fluxes were highly dependent on soil moisture rather than soil temperature.
D. Vickers and C. K. Thomas
Atmos. Chem. Phys., 14, 9665–9676,
G. G. Cirino, R. A. F. Souza, D. K. Adams, and P. Artaxo
Atmos. Chem. Phys., 14, 6523–6543,
L. Hörtnagl, I. Bamberger, M. Graus, T. M. Ruuskanen, R. Schnitzhofer, M. Walser, A. Unterberger, A. Hansel, and G. Wohlfahrt
Atmos. Chem. Phys., 14, 5369–5391,
F. Lohou, L. Kergoat, F. Guichard, A. Boone, B. Cappelaere, J.-M. Cohard, J. Demarty, S. Galle, M. Grippa, C. Peugeot, D. Ramier, C. M. Taylor, and F. Timouk
Atmos. Chem. Phys., 14, 3883–3898,
E. Velasco, M. Roth, S. H. Tan, M. Quak, S. D. A. Nabarro, and L. Norford
Atmos. Chem. Phys., 13, 10185–10202,
G. C. Edwards and D. A. Howard
Atmos. Chem. Phys., 13, 5325–5336,
H. Z. Liu, J. W. Feng, L. Järvi, and T. Vesala
Atmos. Chem. Phys., 12, 7881–7892,
S. Dupont and E. G. Patton
Atmos. Chem. Phys., 12, 5913–5935,
T. Foken, F. X. Meixner, E. Falge, C. Zetzsch, A. Serafimovich, A. Bargsten, T. Behrendt, T. Biermann, C. Breuninger, S. Dix, T. Gerken, M. Hunner, L. Lehmann-Pape, K. Hens, G. Jocher, J. Kesselmeier, J. Lüers, J.-C. Mayer, A. Moravek, D. Plake, M. Riederer, F. Rütz, M. Scheibe, L. Siebicke, M. Sörgel, K. Staudt, I. Trebs, A. Tsokankunku, M. Welling, V. Wolff, and Z. Zhu
Atmos. Chem. Phys., 12, 1923–1950,
Q. Laffineur, M. Aubinet, N. Schoon, C. Amelynck, J.-F. Müller, J. Dewulf, H. Van Langenhove, K. Steppe, and B. Heinesch
Atmos. Chem. Phys., 12, 577–590,
A. L. Steiner, S. N. Pressley, A. Botros, E. Jones, S. H. Chung, and S. L. Edburg
Atmos. Chem. Phys., 11, 11921–11936,
X. Jing, J. Huang, G. Wang, K. Higuchi, J. Bi, Y. Sun, H. Yu, and T. Wang
Atmos. Chem. Phys., 10, 8205–8218,
R. J. Vong, I. J. Vong, D. Vickers, and D. S. Covert
Atmos. Chem. Phys., 10, 5749–5758,
H. K. Lappalainen, S. Sevanto, J. Bäck, T. M. Ruuskanen, P. Kolari, R. Taipale, J. Rinne, M. Kulmala, and P. Hari
Atmos. Chem. Phys., 9, 5447–5459,
Andreae, M. O., Artaxo, P., Brandão, C., Carswell, F. E., Ciccioli, P., da Costa, A. L., Culf, A. D., Esteves, J. L., Gash, J. H. C., Grace, J., Kabat, P., Lelieveld, J., Malhi, Y., Manzi, A. O., Meixner, F. X., Nobre, A. D., Nobre, C., Ruivo, Md. L. P., Silva-Dias, M. A., Stefani, P., Valentini, R., von Jouanne, J., and Waterloo, M. J.: Biogeochemical cycling of carbon, water, energy, trace gases and aerosols in Amazonia: The LBA-EUSTACH experiments, J. Geophys. Res., 107, 8066, https://doi.org/10.1029/2001JD000524, 2002.
Bartlett, K. B. and Harriss, R. C.: Review and assessment of methane emissions from wetlands, Chemosphere, 26, 261–320, 1993.
Bergamaschi, P., Frankenberg, C., Meirink, J. F., Krol, M., Villani, M. G., Houweling, S., Dentener, F., Dlugokencky, E. J., Miller, J. B., Gatti, L. V., Engel, A., and Levin, I.: Inverse modeling of global and regional CH4 emissions using SCIAMACHY satellite retrievals, J. Geophys. Res., 114, D22301, https://doi.org/10.1029/2009JD012287, 2009.
Bousquet, P., Ciais, P., Miller, J. B., Dlugokencky, E. J., Hauglustaine, D. A., Prigent, C., Van der Werf, G. R., Peylin, P., Brunke, E. G., Carouge, C., Langenfelds, R. L., Lathiere, J., Papa, F., Ramonet, M., Schmidt, M., Steele, L. P., Tyler, S. C., and White, J.: Contribution of anthropogenic and natural sources to atmospheric methane variability, Nature, 443, 439–443, 2006.
Chambers, J. Q., Tribuzy, E. S., Toledo, L. C., Crispim, B. F., Higuchi, N., Santos, J. dos, de Araújo, A. C., Kruijt, B., Nobre, A. D., and Trumbore, S.: Respiration from a tropical forest ecosystem: partitioning of sources and low carbon use effi ciency, Ecol. Appl., 14(4), S72–S88, Supplement, 2004.
Culf, A. D., Fisch, G., Malhi, Y., and Nobre, C. A.: The influence of the atmospheric boundary layer on carbon dioxide concentrations over a tropical forest, Agr. Forest Meteorol., 85, 149–158, 1997.
Crutzen, P. J., Sanhueza, E., and Brenninkmeijer, C. A. M.: Methane production from mixed tropical savanna and forest vegetation in Venezuela, Atmos. Chem. Phys. Discuss., 6, 3093–3097, https://doi.org/10.5194/acpd-6-3093-2006, 2006.
de Araújo, A. C., Nobre, A. D., Kruijt, B., Elbers, J. A., Dallarosa, R., Stefani, P., von Randow, C., Manzi, A. O., Culf, A. D., Gash, J. H. C., Valentini, R., and Kabat, P.: Comparative measurements of carbon dioxide fluxes from two nearby towers in a central Amazonian rainforest: The Manaus LBA site, J. Geophys. Res., 107, 8090, https://doi.org/10.1029/2001JD000676, 2002.
de Araújo, A. C., Kruijt, B., Nobre, A. D., Dolman, A. J., Waterloo, M. J., Moors, E. J., and Souza, J. S.: Nocturnal accumulation of CO2 underneath a tropical forest canopy along a topographical gradient, Ecol. Appl., 18(6), 1406–1419, 2008.
de Araújo, A. C., Dolman, A. J., Waterloo, M. J., Gash, J. H. C., Kruijt, B., Zanchi, F. B., de Lange, J. M. E., Stoevelaar, R., Manzi, A. O., Nobre, A. D., Lootens, R. N., and Backer, J.: The spatial variability of CO2 storage and the interpretation of eddy covariance fluxes in central Amazonia, Agr. Forest Meteorol., 150, 226–237, 2010.
do Carmo, J. B., Keller, M, Dias, J. D., Camargo, P. B., and Crill, P.: A source of methane from upland forests in the Brazilian Amazon, Geophys. Res. Lett., 33, L04809, https://doi.org/10.1029/2005GL025436, 2006.
Dlugokencky, E. J., Masarie, K. A., Lang, P. M., and Tans, P. P.: Continuing decline in the growthrate of the atmospheric methane burden, Nature, 393, 447–450, 1998.
Dlugokencky, E. J., Myers, R. C., Lang, P. M., Masarie, K. A., Crotwell, A. M., Thoning, K. W., Hall, B. D., Elkins, J. W., and Steele, L. P.: Conversion of NOAA atmospheric dry air CH4 mole fractions to a gravimetrically prepared standard scale, J. Geophys. Res., 110, D18306, https://doi.org/10.1029/2005JD006035, 2005.
Dlugokencky, E. J., Bruhwiler, L., White, J. W. C., Emmons, L. K., Novelli, P. C., Montzka, S.A., Masarie, K. A., Lang, P. M., Crotwell, A. M., Miller, J. B., and Gatti, L. V.: Observational constraints on recent increases in the atmospheric CH4 burden, Geophys. Res. Lett., 36, L18803, https://doi.org/18810.11029/12009gl039780, 2009.
Etheridge, D. M., Steele, L. P., Francey, R. J., and Langenfields, R. L.: Atmospheric methane between 1000 A.D. and present: Evidence of anthropogenic emissions and climatic variability, J. Geophys. Res., 103, 15979–15993, 1998.
Frankenberg, C., Meirink, J. F., van Weele, M., Platt, U., and Wagner, T.: Assessing methane emissions from global space-borne observations, Science, 308(5724), 1010–1014, https://doi.org/10.1126/science.1106644, 2005.
Frankenberg, C., Bergamaschi, P., Butz, A., Houweling, S., Meirink, J. F., Notholt, J., Petersen, A. K., Schrijver, H., Warneke, T., and Alben, I.: Tropical methane emissions: A revised view from SCIAMACHY onboard ENVISAT, Geophys. Res. Lett., 35, L15811, https://doi.org/10.1029/2008GL034300, 2008.
Goulden, M. L., Miller, S. D., and da Rocha, H. R.: Nocturnal cold air drainage and pooling in a tropical forest, J. Geophys. Res., 11, D08S04, https://doi.org/10.1029/2005JD006037, 2006.
Hendriks, D. M. D., Dolman, A. J., van der Molen, M. K., and van Huissteden, J.: A compact and stable eddy covariance set-up for methane measurements using off-axis integrated cavity output spectroscopy, Atmos. Chem. Phys., 8, 431–443, https://doi.org/10.5194/acp-8-431-2008, 2008.
IPCC: Fourth Assessment Report, Climate Change, Cambridge University Press, Cambridge, 2007.
Itoh, M., Ohte, N., and Koba, K.: Methane flux characteristics in forest soils under an East Asian monsoon climate, Soil Biol. Biochem., 41(2), 388–395, 2009.
Ibrom, A., Dellwik, E., Flyvbjerg, H., Jensen, N. O., and Pilegaard, K.: Strong low-pass filtering effects on water vapour flux measurements with closed-path eddy correlation systems, Agr. Forest Meteorol., 147, 140–156, 2007.
Janssens, I. A., Kowalski, A. S., and Ceulemans, R.: Forest floor CO2 fluxes estimated by eddy covariance and chamber-based model, Agr. Forest Meteorol., 106, 61–69, 2001.
Kaimal, J. C.: Turbulence spectra, length scales and structure parameters in the stable surface layer, Boundary Layer Meteorol., 4, 289–309, 1973.
Kaimal, J. C., Wyngaard, J. C., Izumi, Y., and Cote, O. R.: Spectral characteristics of surface layer turbulence, Q. J. Roy. Meteorol. Soc., 98, 653–689, 1972.
Keller, M. and Matson, P. A.: Biosphere-atmosphere exchange of trace gases in the tropics, in: Evaluating the eff ect of land-use changes, in: Global Atmospheric, Biospheric Chemistry, edited by: Prinn, R. G., Biospheric Chemistry, Plenum, New York, 103–117, 1994.
Kroon, P. S., Hensen, A., Jonker, H. J. J., Zahniser, M. S., van 't Veen, W. H., and Vermeulen, A. T.: Suitability of quantum cascade laser spectroscopy for CH4 and N2O eddy covariance flux measurements, Biogeosciences, 4, 715–728, https://doi.org/10.5194/bg-4-715-2007, 2007.
Lelieveld, J., Crutzen, P. J., and Dentener, F. J.: Changing concentration, lifetimes and climate forcing of atmospheric methane, Tellus, 50, 128–150, 1998.
Luizão, R. C. C., Luizão, F. J., Paiva, R. Q., Monteiro, T. F., Sousa, L. S., and Kruijt, B.: Variation of carbon and nitrogen cycling processes along a topographic gradient in a Central Amazonian forest, Glob. Change Biol., 10(5), 592–600, https://doi.org/10.1111/j.1529-8817.2003.00757.x, 2004.
Malhi, Y. and Grace, J.: Tropical forests and atmospheric carbon dioxide, Trends Ecol. Evolut., 15, 332–337, 2000.
Malhi, Y., Baldocchi, D. D., and Jarvis, P. G.: The carbon balance of tropical, temperate and boreal forests, Plant Cell Environ., 22, 715–740, 1999.
McLeod, A. R., Fry, S. C., Loake, G. J., Messenger, D. J., Reay, D. S., Smith, K. A., and Yun, B. W.: Ultraviolet radiation drives methane emissions from terrestrial plant pectins, New Phytol., 180(1), 124–132, 2008.
Megonigal, J. P. and Guenther, A. B.: Methane emissions from upland forest soils and vegetation, Tree Physiol., 28, 491–498, 2008.
Meirink, J. F., Bergamaschi, P., Frankenberg, C., d'Amélio, M. T. S., Dlugokencky, E. J.,Gatti, L. V., Houweling, S., Miller, J. B., Röckmann, T., Villani, M. G., and Krol, M. C.: Four-dimensional variational data assimilation for inverse modeling of atmospheric methane emissions: Analysis of SCIAMACHY observations, J. Geophys. Res., 113, D17301, https://doi.org/17310.11029/12007JD009740, 2008.
Miller, J. B., Mack, K. A., Dissly, R., White, J. W. C., Dlugokencky, E. J., and Tans, P. P.: Development of analytical methods and measurements of 13 C/12 C in atmospheric CH4 from the NOAA/CMDL global air sampling network, J. Geophys. Res., 107(D13), 4178, https://doi.org/10.1029/2001JD000630, 2002.
Miller, J. B., Gatti, L. V., d'Amélio, M. T. S., Crotwell, A. M., Dlugokencky, E. J., Bakwin, P., Artaxo, P., and Tans, P. P.: Airbone measurements indicate large methane emissions from the eastern Amazon basin, Geophys. Res. Lett., 34, L10809, https://doi.org/10.1029/2006GL029213, 2007.
Molion, L. C. B.: A Amazônia e o clima da Terra, Ciencia Hoje, 48(8), 42–47, 1988.
Prance, G.: Encyclopedia of Biodiversity, Academic Press, 1, 145–157, 2001.
Quay, P., Stutsman, J., Wilbur, D., Snover, A., Dlugokencky, E., and Brown, T.: The isotopic composition of atmospheric methane, Global Biogeochem. Cy., 13, 445–461, 1999.
Sanhueza, E. and Donoso, L.: Methane emission from tropical savanna Trachypogon sp. grasses, Atmos. Chem. Phys., 6, 5315–5319, https://doi.org/10.5194/acp-6-5315-2006, 2006.
Simon E., Lehamann, B. E., Ammann, C., Ganzeveld, L., Rummel, U., Meixner, F. X., Nobre, A. D., de Araújo, A., and Kesselmeier, J.: Lagrangian dispersion of 222Rn, H2O and CO2 within Amazonian rain forest, Agr. Forest Meteorol., 132, 286–304, 2005.
Singh, J. S., Singh, S., Raghubanshi, A. S., Singh, S., Kashyap, A. K., and Reddy, V. S.: Effects of soil nitrogen, carbon and moisture on methane uptake by dry tropical forest soils, Plant Soil, 196, 115–121, 1997.
Smeets, C. J. P. P., Holzinger, R., Vigano, I., Goldstein, A. H., and Röckmann, T.: Eddy covariance methane measurements at a Ponderosa pine plantation in California, Atmos. Chem. Phys., 9, 8365–8375, https://doi.org/10.5194/acp-9-8365-2009, 2009.
Steudler, P. A., Melillo, J. M., Feigl, B. J., Neill, C., Piccolo, M. C., and Cerri, C. C.: Consequence of forest-to-pasture conversion on CH4 fluxes in the Brazilian Amazon Basin, J. Geophys. Res., 101(18), 547–554, 1996.
Tóta, J., Fitzjarrald, D. R., Staebler, R. M., Sakai, R. K., Moraes, O. M. M., Acevedo, O. C., Wofsy, S. C., and Manzi, A. O.: Amazon rain forest subcanopy flow and the carbon budget: Santare'm LBA-ECO site, J. Geophys. Res.-Biogeo, 113(15), G00B02, https://doi.org/10.1029/2007JG000597, 2008.
Tuzson, B., Hiller, R. V., Zeyer, K., Eugster, W., Neftel, A., Ammann, C., and Emmenegger, L.: Field intercomparison of two optical analyzers for CH4 eddy covariance flux measurements, Atmos. Meas. Tech., 3, 1519–1531, https://doi.org/10.5194/amt-3-1519-2010, 2010.
Veldkamp, E., Keller, M., and Nunez, M.: Eff ects of pasture management on N2O and NO emissions from soils in the humid tropics of Costa Rica, Global Biogeochem. Cy., 12, 71–79, 1998.
Vigano, I., van Weelden, H., Holzinger, R., Keppler, F., McLeod, A., and Röckmann, T.: Effect of UV radiation and temperature on the emission of methane from plant biomass and structural components, Biogeosciences, 5, 937–947, https://doi.org/10.5194/bg-5-937-2008, 2008.
Wienhold, F. G., Welling, M., and Harris, G. W.: Micrometeorological measurements and source region analysis of nitrous oxide fluxes from an agricultural soil, Atmos. Environ., 29(17), 2219–2227, 1995.