Knohl, Alexander

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[["dc.bibliographiccitation.firstpage","734"],["dc.bibliographiccitation.issue","4"],["dc.bibliographiccitation.journal","Global Change Biology"],["dc.bibliographiccitation.lastpage","760"],["dc.bibliographiccitation.volume","13"],["dc.contributor.author","OWEN, KATHERINE E."],["dc.contributor.author","Tenhunen, John"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Wang, Qiang"],["dc.contributor.author","Falge, Eva"],["dc.contributor.author","GEYER, RALF"],["dc.contributor.author","XIAO, XIANGMING"],["dc.contributor.author","STOY, PAUL"],["dc.contributor.author","Ammann, Christof"],["dc.contributor.author","Arain, Altaf"],["dc.contributor.author","Aubinet, Marc"],["dc.contributor.author","Aurela, Mika"],["dc.contributor.author","Bernhofer, Christian"],["dc.contributor.author","CHOJNICKI, BOGDAN H."],["dc.contributor.author","Granier, Andre"],["dc.contributor.author","GRUENWALD, THOMAS"],["dc.contributor.author","HADLEY, JULIAN"],["dc.contributor.author","Heinesch, Bernard"],["dc.contributor.author","Hollinger, David"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Kutsch, Werner L."],["dc.contributor.author","Lohila, Annalea"],["dc.contributor.author","Meyers, Tilden"],["dc.contributor.author","Moors, Eddy"],["dc.contributor.author","Moureaux, Christine"],["dc.contributor.author","Pilegaard, Kim"],["dc.contributor.author","Saigusa, Nobuko"],["dc.contributor.author","Verma, Shashi"],["dc.contributor.author","Vesala, Timo"],["dc.contributor.author","VOGEL, CHRIS"],["dc.date.accessioned","2017-09-07T11:50:03Z"],["dc.date.available","2017-09-07T11:50:03Z"],["dc.date.issued","2010"],["dc.identifier.doi","10.1111/j.1365-2486.2007.01326.x"],["dc.identifier.gro","3147551"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5054"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","chake"],["dc.relation.issn","1354-1013"],["dc.title","Linking flux network measurements to continental scale simulations: ecosystem carbon dioxide exchange capacity under non-water-stressed conditions"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","Global Biogeochemical Cycles"],["dc.bibliographiccitation.volume","23"],["dc.contributor.author","Beer, C."],["dc.contributor.author","Ciais, Philippe"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Baldocchi, Dennis D."],["dc.contributor.author","Law, Beverly E."],["dc.contributor.author","Papale, Dario"],["dc.contributor.author","Soussana, Jean-François"],["dc.contributor.author","Ammann, Christof"],["dc.contributor.author","Buchmann, Nina"],["dc.contributor.author","Frank, D."],["dc.contributor.author","Gianelle, Damiano"],["dc.contributor.author","Janssens, Ivan A."],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Köstner, B."],["dc.contributor.author","Moors, Eddy"],["dc.contributor.author","Roupsard, Olivier"],["dc.contributor.author","Verbeeck, H."],["dc.contributor.author","Vesala, Timo"],["dc.contributor.author","Williams, Christopher A"],["dc.contributor.author","Wohlfahrt, Georg"],["dc.date.accessioned","2017-09-07T11:48:43Z"],["dc.date.available","2017-09-07T11:48:43Z"],["dc.date.issued","2009"],["dc.identifier.doi","10.1029/2008gb003233"],["dc.identifier.gro","3147057"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/4787"],["dc.notes.status","public"],["dc.notes.submitter","chake"],["dc.relation.issn","0886-6236"],["dc.relation.orgunit","Abteilung Bioklimatologie"],["dc.title","Temporal and among-site variability of inherent water use efficiency at the ecosystem level"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","no"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","634"],["dc.bibliographiccitation.issue","3"],["dc.bibliographiccitation.journal","Global Change Biology"],["dc.bibliographiccitation.lastpage","651"],["dc.bibliographiccitation.volume","13"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Ciais, Philippe"],["dc.contributor.author","Papale, Dario"],["dc.contributor.author","Valentini, Riccardo"],["dc.contributor.author","Running, S."],["dc.contributor.author","Viovy, N."],["dc.contributor.author","Cramer, Wolfgang"],["dc.contributor.author","Granier, Andre"],["dc.contributor.author","Ogée, Jérôme"],["dc.contributor.author","Allard, V."],["dc.contributor.author","Aubinet, Marc"],["dc.contributor.author","Bernhofer, Christian"],["dc.contributor.author","Buchmann, Nina"],["dc.contributor.author","Carrara, A."],["dc.contributor.author","Grünwald, Thomas"],["dc.contributor.author","Heimann, Martin"],["dc.contributor.author","Heinesch, Bernard"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Kutsch, Werner L."],["dc.contributor.author","Loustau, Denis"],["dc.contributor.author","Manca, Giovanni"],["dc.contributor.author","Matteucci, Giorgio"],["dc.contributor.author","Miglietta, Franco"],["dc.contributor.author","Ourcival, Jean-Marc"],["dc.contributor.author","Pilegaard, Kim"],["dc.contributor.author","Pumpanen, J."],["dc.contributor.author","Rambal, Serge"],["dc.contributor.author","Schaphoff, S."],["dc.contributor.author","Seufert, Günther"],["dc.contributor.author","Soussana, Jean-François"],["dc.contributor.author","Sanz, María José"],["dc.contributor.author","Vesala, Timo"],["dc.contributor.author","Zhao, M."],["dc.date.accessioned","2017-09-07T11:50:01Z"],["dc.date.available","2017-09-07T11:50:01Z"],["dc.date.issued","2006"],["dc.identifier.doi","10.1111/j.1365-2486.2006.01224.x"],["dc.identifier.gro","3147554"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/5057"],["dc.notes.status","public"],["dc.notes.submitter","chake"],["dc.publisher","Wiley-Blackwell"],["dc.relation.issn","1354-1013"],["dc.title","Reduction of ecosystem productivity and respiration during the European summer 2003 climate anomaly: a joint flux tower, remote sensing and modelling analysis"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","e0211510"],["dc.bibliographiccitation.issue","2"],["dc.bibliographiccitation.journal","PlOS ONE"],["dc.bibliographiccitation.volume","14"],["dc.contributor.author","Besnard, Simon"],["dc.contributor.author","Carvalhais, Nuno"],["dc.contributor.author","Arain, M Altaf"],["dc.contributor.author","Black, Andrew"],["dc.contributor.author","Brede, Benjamin"],["dc.contributor.author","Buchmann, Nina"],["dc.contributor.author","Chen, Jiquan"],["dc.contributor.author","Clevers, Jan G. P. W."],["dc.contributor.author","Dutrieux, Loïc P."],["dc.contributor.author","Gans, Fabian"],["dc.contributor.author","Herold, Martin"],["dc.contributor.author","Jung, Martin"],["dc.contributor.author","Kosugi, Yoshiko"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Law, Beverly E."],["dc.contributor.author","Paul-Limoges, Eugénie"],["dc.contributor.author","Lohila, Annalea"],["dc.contributor.author","Merbold, Lutz"],["dc.contributor.author","Roupsard, Olivier"],["dc.contributor.author","Valentini, Riccardo"],["dc.contributor.author","Wolf, Sebastian"],["dc.contributor.author","Zhang, Xudong"],["dc.contributor.author","Reichstein, Markus"],["dc.date.accessioned","2019-07-09T11:50:19Z"],["dc.date.available","2019-07-09T11:50:19Z"],["dc.date.issued","2019"],["dc.description.abstract","Forests play a crucial role in the global carbon (C) cycle by storing and sequestering a substantial amount of C in the terrestrial biosphere. Due to temporal dynamics in climate and vegetation activity, there are significant regional variations in carbon dioxide (CO2) fluxes between the biosphere and atmosphere in forests that are affecting the global C cycle. Current forest CO2 flux dynamics are controlled by instantaneous climate, soil, and vegetation conditions, which carry legacy effects from disturbances and extreme climate events. Our level of understanding from the legacies of these processes on net CO2 fluxes is still limited due to their complexities and their long-term effects. Here, we combined remote sensing, climate, and eddy-covariance flux data to study net ecosystem CO2 exchange (NEE) at 185 forest sites globally. Instead of commonly used non-dynamic statistical methods, we employed a type of recurrent neural network (RNN), called Long Short-Term Memory network (LSTM) that captures information from the vegetation and climate's temporal dynamics. The resulting data-driven model integrates interannual and seasonal variations of climate and vegetation by using Landsat and climate data at each site. The presented LSTM algorithm was able to effectively describe the overall seasonal variability (Nash-Sutcliffe efficiency, NSE = 0.66) and across-site (NSE = 0.42) variations in NEE, while it had less success in predicting specific seasonal and interannual anomalies (NSE = 0.07). This analysis demonstrated that an LSTM approach with embedded climate and vegetation memory effects outperformed a non-dynamic statistical model (i.e. Random Forest) for estimating NEE. Additionally, it is shown that the vegetation mean seasonal cycle embeds most of the information content to realistically explain the spatial and seasonal variations in NEE. These findings show the relevance of capturing memory effects from both climate and vegetation in quantifying spatio-temporal variations in forest NEE."],["dc.identifier.doi","10.1371/journal.pone.0211510"],["dc.identifier.pmid","30726269"],["dc.identifier.purl","https://resolver.sub.uni-goettingen.de/purl?gs-1/15909"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/59746"],["dc.language.iso","en"],["dc.relation.issn","1932-6203"],["dc.relation.orgunit","Abteilung Bioklimatologie"],["dc.subject.ddc","570"],["dc.title","Memory effects of climate and vegetation affecting net ecosystem CO2 fluxes in global forests"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.artnumber","124018"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Environmental Research Letters"],["dc.bibliographiccitation.volume","13"],["dc.contributor.affiliation","Besnard, Simon;"],["dc.contributor.affiliation","Carvalhais, Nuno;"],["dc.contributor.affiliation","Arain, M Altaf;"],["dc.contributor.affiliation","Black, Andrew;"],["dc.contributor.affiliation","de Bruin, Sytze;"],["dc.contributor.affiliation","Buchmann, Nina;"],["dc.contributor.affiliation","Cescatti, Alessandro;"],["dc.contributor.affiliation","Chen, Jiquan;"],["dc.contributor.affiliation","Clevers, Jan G P W;"],["dc.contributor.affiliation","Desai, Ankur R;"],["dc.contributor.affiliation","Gough, Christopher M;"],["dc.contributor.affiliation","Havrankova, Katerina;"],["dc.contributor.affiliation","Herold, Martin;"],["dc.contributor.affiliation","Hörtnagl, Lukas;"],["dc.contributor.affiliation","Jung, Martin;"],["dc.contributor.affiliation","Knohl, Alexander;"],["dc.contributor.affiliation","Kruijt, Bart;"],["dc.contributor.affiliation","Krupkova, Lenka;"],["dc.contributor.affiliation","Law, Beverly E;"],["dc.contributor.affiliation","Lindroth, Anders;"],["dc.contributor.affiliation","Noormets, Asko;"],["dc.contributor.affiliation","Roupsard, Olivier;"],["dc.contributor.affiliation","Steinbrecher, Rainer;"],["dc.contributor.affiliation","Varlagin, Andrej;"],["dc.contributor.affiliation","Vincke, Caroline;"],["dc.contributor.affiliation","Reichstein, Markus;"],["dc.contributor.author","Besnard, Simon"],["dc.contributor.author","Carvalhais, Nuno"],["dc.contributor.author","Arain, M Altaf"],["dc.contributor.author","Black, Andrew"],["dc.contributor.author","de Bruin, Sytze"],["dc.contributor.author","Buchmann, Nina"],["dc.contributor.author","Cescatti, Alessandro"],["dc.contributor.author","Chen, Jiquan"],["dc.contributor.author","Clevers, Jan G. P. W."],["dc.contributor.author","Desai, Ankur R."],["dc.contributor.author","Gough, Christopher M."],["dc.contributor.author","Havrankova, Katerina"],["dc.contributor.author","Herold, Martin"],["dc.contributor.author","Hörtnagl, Lukas"],["dc.contributor.author","Jung, Martin"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Kruijt, Bart"],["dc.contributor.author","Krupkova, Lenka"],["dc.contributor.author","Law, Beverly E."],["dc.contributor.author","Lindroth, Anders"],["dc.contributor.author","Noormets, Asko"],["dc.contributor.author","Roupsard, Olivier"],["dc.contributor.author","Steinbrecher, Rainer"],["dc.contributor.author","Varlagin, Andrej"],["dc.contributor.author","Vincke, Caroline"],["dc.contributor.author","Reichstein, Markus"],["dc.date.accessioned","2019-11-14T15:44:11Z"],["dc.date.available","2019-11-14T15:44:11Z"],["dc.date.issued","2018"],["dc.date.updated","2022-02-09T13:19:01Z"],["dc.description.abstract","Forests dominate carbon (C) exchanges between the terrestrial biosphere and the atmosphere on land. In the long term, the net carbon flux between forests and the atmosphere has been significantly impacted by changes in forest cover area and structure due to ecological disturbances and management activities. Current empirical approaches for estimating net ecosystem productivity (NEP) rarely consider forest age as a predictor, which represents variation in physiological processes that can respond differently to environmental drivers, and regrowth following disturbance. Here, we conduct an observational synthesis to empirically determine to what extent climate, soil properties, nitrogen deposition, forest age and management influence the spatial and interannual variability of forest NEP across 126 forest eddy-covariance flux sites worldwide. The empirical models explained up to 62% and 71% of spatio-temporal and across-site variability of annual NEP, respectively. An investigation of model structures revealed that forest age was a dominant factor of NEP spatio-temporal variability in both space and time at the global scale as compared to abiotic factors such as nutrient availability, soil characteristics, and climate. These findings emphasize the importance of forest age in quantifying spatio-temporal variation in NEP using empirical approaches."],["dc.identifier.doi","10.1088/1748-9326/aaeaeb"],["dc.identifier.eissn","1748-9326"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/62627"],["dc.language.iso","en"],["dc.relation.issn","1748-9326"],["dc.relation.orgunit","Abteilung Bioklimatologie"],["dc.rights.uri","http://creativecommons.org/licenses/by/3.0/"],["dc.title","Quantifying the effect of forest age in annual net forest carbon balance"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","6916"],["dc.bibliographiccitation.issue","12"],["dc.bibliographiccitation.journal","Global Change Biology"],["dc.bibliographiccitation.lastpage","6930"],["dc.bibliographiccitation.volume","26"],["dc.contributor.author","Nelson, Jacob A."],["dc.contributor.author","Pérez‐Priego, Oscar"],["dc.contributor.author","Zhou, Sha"],["dc.contributor.author","Poyatos, Rafael"],["dc.contributor.author","Zhang, Yao"],["dc.contributor.author","Blanken, Peter D."],["dc.contributor.author","Gimeno, Teresa E."],["dc.contributor.author","Wohlfahrt, Georg"],["dc.contributor.author","Desai, Ankur R."],["dc.contributor.author","Gioli, Beniamino"],["dc.contributor.author","Limousin, Jean‐Marc"],["dc.contributor.author","Bonal, Damien"],["dc.contributor.author","Paul‐Limoges, Eugénie"],["dc.contributor.author","Scott, Russell L."],["dc.contributor.author","Varlagin, Andrej"],["dc.contributor.author","Fuchs, Kathrin"],["dc.contributor.author","Montagnani, Leonardo"],["dc.contributor.author","Wolf, Sebastian"],["dc.contributor.author","Delpierre, Nicolas"],["dc.contributor.author","Berveiller, Daniel"],["dc.contributor.author","Gharun, Mana"],["dc.contributor.author","Belelli Marchesini, Luca"],["dc.contributor.author","Gianelle, Damiano"],["dc.contributor.author","Šigut, Ladislav"],["dc.contributor.author","Mammarella, Ivan"],["dc.contributor.author","Siebicke, Lukas"],["dc.contributor.author","Andrew Black, T."],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Hörtnagl, Lukas"],["dc.contributor.author","Magliulo, Vincenzo"],["dc.contributor.author","Besnard, Simon"],["dc.contributor.author","Weber, Ulrich"],["dc.contributor.author","Carvalhais, Nuno"],["dc.contributor.author","Migliavacca, Mirco"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Jung, Martin"],["dc.date.accessioned","2021-04-14T08:31:30Z"],["dc.date.available","2021-04-14T08:31:30Z"],["dc.date.issued","2020"],["dc.description.abstract","We apply and compare three widely applicable methods for estimating ecosystem transpiration (T) from eddy covariance (EC) data across 251 FLUXNET sites globally. All three methods are based on the coupled water and carbon relationship, but they differ in assumptions and parameterizations. Intercomparison of the three daily T estimates shows high correlation among methods (R between .89 and .94), but a spread in magnitudes of T/ET (evapotranspiration) from 45% to 77%. When compared at six sites with concurrent EC and sap flow measurements, all three EC-based T estimates show higher correlation to sap flow-based T than EC-based ET. The partitioning methods show expected tendencies of T/ET increasing with dryness (vapor pressure deficit and days since rain) and with leaf area index (LAI). Analysis of 140 sites with high-quality estimates for at least two continuous years shows that T/ET variability was 1.6 times higher across sites than across years. Spatial variability of T/ET was primarily driven by vegetation and soil characteristics (e.g., crop or grass designation, minimum annual LAI, soil coarse fragment volume) rather than climatic variables such as mean/standard deviation of temperature or precipitation. Overall, T and T/ET patterns are plausible and qualitatively consistent among the different water flux partitioning methods implying a significant advance made for estimating and understanding T globally, while the magnitudes remain uncertain. Our results represent the first extensive EC data-based estimates of ecosystem T permitting a data-driven perspective on the role of plants’ water use for global water and carbon cycling in a changing climate."],["dc.identifier.doi","10.1111/gcb.15314"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/83614"],["dc.language.iso","en"],["dc.notes.intern","DOI Import GROB-399"],["dc.relation.eissn","1365-2486"],["dc.relation.issn","1354-1013"],["dc.relation.orgunit","Abteilung Bioklimatologie"],["dc.rights","CC BY 4.0"],["dc.title","Ecosystem transpiration and evaporation: Insights from three water flux partitioning methods across FLUXNET sites"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1293"],["dc.bibliographiccitation.issue","5"],["dc.bibliographiccitation.journal","Biogeosciences"],["dc.bibliographiccitation.lastpage","1318"],["dc.bibliographiccitation.volume","15"],["dc.contributor.author","Buttlar, Jannis von"],["dc.contributor.author","Zscheischler, Jakob"],["dc.contributor.author","Rammig, Anja"],["dc.contributor.author","Sippel, Sebastian"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Jung, Martin"],["dc.contributor.author","Menzer, Olaf"],["dc.contributor.author","Arain, M. Altaf"],["dc.contributor.author","Buchmann, Nina"],["dc.contributor.author","Cescatti, Alessandro"],["dc.contributor.author","Gianelle, Damiano"],["dc.contributor.author","Kiely, Gerard"],["dc.contributor.author","Law, Beverly E."],["dc.contributor.author","Magliulo, Vincenzo"],["dc.contributor.author","Margolis, Hank A"],["dc.contributor.author","McCaughey, Harry"],["dc.contributor.author","Lutz, Merbold"],["dc.contributor.author","Migliavacca, Mirco"],["dc.contributor.author","Montagnani, Leonardo"],["dc.contributor.author","Oechel, Walter"],["dc.contributor.author","Pavelka, Marian"],["dc.contributor.author","Peichl, Matthias"],["dc.contributor.author","Rambal, Serge"],["dc.contributor.author","Raschi, Antonio"],["dc.contributor.author","Scott, Russell L."],["dc.contributor.author","Vaccari, Francesco P."],["dc.contributor.author","van Gorsel, Eva"],["dc.contributor.author","Varlagin, Andrej B."],["dc.contributor.author","Wohlfahrt, Georg"],["dc.contributor.author","Mahecha, Miguel D."],["dc.date.accessioned","2019-11-18T14:50:17Z"],["dc.date.available","2019-11-18T14:50:17Z"],["dc.date.issued","2018"],["dc.description.abstract","Extreme climatic events, such as droughts and heat stress, induce anomalies in ecosystem–atmosphere CO2 fluxes, such as gross primary production (GPP) and ecosystem respiration (Reco), and, hence, can change the net ecosystem carbon balance. However, despite our increasing understanding of the underlying mechanisms, the magnitudes of the impacts of different types of extremes on GPP and Reco within and between ecosystems remain poorly predicted. Here we aim to identify the major factors controlling the amplitude of extreme-event impacts on GPP, Reco, and the resulting net ecosystem production (NEP). We focus on the impacts of heat and drought and their combination. We identified hydrometeorological extreme events in consistently downscaled water availability and temperature measurements over a 30-year time period. We then used FLUXNET eddy covariance flux measurements to estimate the CO2 flux anomalies during these extreme events across dominant vegetation types and climate zones. Overall, our results indicate that short-term heat extremes increased respiration more strongly than they downregulated GPP, resulting in a moderate reduction in the ecosystem's carbon sink potential. In the absence of heat stress, droughts tended to have smaller and similarly dampening effects on both GPP and Reco and, hence, often resulted in neutral NEP responses. The combination of drought and heat typically led to a strong decrease in GPP, whereas heat and drought impacts on respiration partially offset each other. Taken together, compound heat and drought events led to the strongest C sink reduction compared to any single-factor extreme. A key insight of this paper, however, is that duration matters most: for heat stress during droughts, the magnitude of impacts systematically increased with duration, whereas under heat stress without drought, the response of Reco over time turned from an initial increase to a downregulation after about 2 weeks. This confirms earlier theories that not only the magnitude but also the duration of an extreme event determines its impact. Our study corroborates the results of several local site-level case studies but as a novelty generalizes these findings on the global scale. Specifically, we find that the different response functions of the two antipodal land–atmosphere fluxes GPP and Reco can also result in increasing NEP during certain extreme conditions. Apparently counterintuitive findings of this kind bear great potential for scrutinizing the mechanisms implemented in state-of-the-art terrestrial biosphere models and provide a benchmark for future model development and testing."],["dc.identifier.doi","10.5194/bg-15-1293-2018"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/62655"],["dc.language.iso","en"],["dc.relation.issn","1726-4189"],["dc.relation.orgunit","Abteilung Bioklimatologie"],["dc.rights","CC BY 4.0"],["dc.title","Impacts of droughts and extreme-temperature events on gross primary production and ecosystem respiration: a systematic assessment across ecosystems and climate zones"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.subtype","original_ja"],["dc.type.version","published_version"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","137"],["dc.bibliographiccitation.journal","Agricultural and Forest Meteorology"],["dc.bibliographiccitation.lastpage","152"],["dc.bibliographiccitation.volume","171"],["dc.contributor.author","Stoy, Paul C."],["dc.contributor.author","Mauder, Matthias"],["dc.contributor.author","Foken, Thomas"],["dc.contributor.author","Marcolla, Barbara"],["dc.contributor.author","Boegh, Eva"],["dc.contributor.author","Ibrom, Andreas"],["dc.contributor.author","Arain, M. Altaf"],["dc.contributor.author","Arneth, Almut"],["dc.contributor.author","Aurela, Mika"],["dc.contributor.author","Bernhofer, Christian"],["dc.contributor.author","Cescatti, Alessandro"],["dc.contributor.author","Dellwik, Ebba"],["dc.contributor.author","Duce, Pierpaolo"],["dc.contributor.author","Gianelle, Damiano"],["dc.contributor.author","van Gorsel, Eva"],["dc.contributor.author","Kiely, Gerard"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Margolis, Hank"],["dc.contributor.author","McCaughey, Harry"],["dc.contributor.author","Merbold, Lutz"],["dc.contributor.author","Montagnani, Leonardo"],["dc.contributor.author","Papale, Dario"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Saunders, Matthew"],["dc.contributor.author","Serrano-Ortiz, Penelope"],["dc.contributor.author","Sottocornola, Matteo"],["dc.contributor.author","Spano, Donatella"],["dc.contributor.author","Vaccari, Francesco"],["dc.contributor.author","Varlagin, Andrej"],["dc.date.accessioned","2018-11-07T09:26:00Z"],["dc.date.available","2018-11-07T09:26:00Z"],["dc.date.issued","2013"],["dc.description.abstract","The energy balance at most surface-atmosphere flux research sites remains unclosed. The mechanisms underlying the discrepancy between measured energy inputs and outputs across the global FLUXNET tower network are still under debate. Recent reviews have identified exchange processes and turbulent motions at large spatial and temporal scales in heterogeneous landscapes as the primary cause of the lack of energy balance closure at some intensively-researched sites, while unmeasured storage terms cannot be ruled out as a dominant contributor to the lack of energy balance closure at many other sites. We analyzed energy balance closure across 173 ecosystems in the FLUXNET database and explored the relationship between energy balance closure and landscape heterogeneity using MODIS products and GLOBEstat elevation data. Energy balance closure per research site (C-EBS)averaged 0.84 +/- 0.20, with best average closures in evergreen broadleaf forests and savannas (0.91-0.94) and worst average closures in crops, deciduous broadleaf forests, mixed forests and wetlands (0.70-0.78). Half-hourly or hourly energy balance closure on a percent basis increased with friction velocity (u.) and was highest on average under near-neutral atmospheric conditions. C-EBS was significantly related to mean precipitation, gross primary productivity and landscape-level enhanced vegetation index (EVI) from MODIS, and the variability in elevation, MODIS plant functional type, and MODIS EVI. A linear model including landscape-level variability in both EVI and elevation, mean precipitation, and an interaction term between EVI variability and precipitation had the lowest Akaike's information criterion value. C-EBS in landscapes with uniform plant functional type approached 0.9 and C-EBS in landscapes with uniform EVI approached 1. These results suggest that landscape-level heterogeneity in vegetation and topography cannot be ignored as a contributor to incomplete energy balance closure at the flux network level, although net radiation measurements, biological energy assimilation, unmeasured storage terms, and the importance of good practice including site selection when making flux measurements should not be discounted. Our results suggest that future research should focus on the quantitative mechanistic relationships between energy balance closure and landscape-scale heterogeneity, and the consequences of mesoscale circulations for surface-atmosphere exchange measurements. (C) 2012 Elsevier B.V. All rights reserved."],["dc.identifier.doi","10.1016/j.agrformet.2012.11.004"],["dc.identifier.isi","000316513000014"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/30198"],["dc.notes.status","zu prüfen"],["dc.notes.submitter","Najko"],["dc.relation.issn","1873-2240"],["dc.relation.issn","0168-1923"],["dc.relation.orgunit","Abteilung Bioklimatologie"],["dc.title","A data-driven analysis of energy balance closure across FLUXNET research sites: The role of landscape scale heterogeneity"],["dc.type","journal_article"],["dc.type.internalPublication","yes"],["dc.type.peerReviewed","yes"],["dc.type.subtype","original_ja"],["dspace.entity.type","Publication"]]

[["dc.bibliographiccitation.firstpage","1424"],["dc.bibliographiccitation.issue","9"],["dc.bibliographiccitation.journal","Global Change Biology"],["dc.bibliographiccitation.lastpage","1439"],["dc.bibliographiccitation.volume","11"],["dc.contributor.author","Reichstein, Markus"],["dc.contributor.author","Falge, Eva"],["dc.contributor.author","Baldocchi, Dennis D."],["dc.contributor.author","Papale, Dario"],["dc.contributor.author","Aubinet, Marc"],["dc.contributor.author","Berbigier, Paul"],["dc.contributor.author","Bernhofer, Christian"],["dc.contributor.author","Buchmann, Nina"],["dc.contributor.author","Gilmanov, Tagir"],["dc.contributor.author","Granier, Andre"],["dc.contributor.author","Grünwald, Thomas"],["dc.contributor.author","Havrankova, Katka"],["dc.contributor.author","Ilvesniemi, Hannu"],["dc.contributor.author","Janous, Dalibor"],["dc.contributor.author","Knohl, Alexander"],["dc.contributor.author","Laurila, Tuomas"],["dc.contributor.author","Lohila, Annalea"],["dc.contributor.author","Loustau, Denis"],["dc.contributor.author","Matteucci, Giorgio"],["dc.contributor.author","Meyers, Tilden"],["dc.contributor.author","Miglietta, Franco"],["dc.contributor.author","Ourcival, Jean-Marc"],["dc.contributor.author","Pumpanen, Jukka"],["dc.contributor.author","Rambal, Serge"],["dc.contributor.author","Rotenberg, Eyal"],["dc.contributor.author","Sanz, María José"],["dc.contributor.author","Tenhunen, John"],["dc.contributor.author","Seufert, Günther"],["dc.contributor.author","Vaccari, Francesco"],["dc.contributor.author","Vesala, Timo"],["dc.contributor.author","Yakir, Dan"],["dc.contributor.author","Valentini, Riccardo"],["dc.date.accessioned","2017-09-07T11:49:08Z"],["dc.date.available","2017-09-07T11:49:08Z"],["dc.date.issued","2005"],["dc.identifier.doi","10.1111/j.1365-2486.2005.001002.x"],["dc.identifier.gro","3147102"],["dc.identifier.uri","https://resolver.sub.uni-goettingen.de/purl?gro-2/4817"],["dc.notes.status","public"],["dc.notes.submitter","chake"],["dc.relation.issn","1354-1013"],["dc.title","On the separation of net ecosystem exchange into assimilation and ecosystem respiration: review and improved algorithm"],["dc.type","journal_article"],["dc.type.internalPublication","unknown"],["dc.type.peerReviewed","no"],["dspace.entity.type","Publication"]]