Browsing by Subject "ASSIMILATION"

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  • Fernandez-Prieto, D.; Kesselmeier, J.; Ellis, M.; Marconcini, M.; Reissell, A.; Suni, T. (2013)
  • Peltoniemi, Mikko; Markkanen, Tiina; Härkönen, Sanna; Muukkonen, Petteri; Thum, Tea; Aalto, Tuula; Mäkelä, Annikki (2015)
    We simulated Gross Primary Production (GPP) of Finnish forests using a landsurface model (LSM), JSBACH, and a semi-empirical stand-flux model PRELES, and compared their predictions with the MODIS GPP product. JSBACH used information about plant functional type fractions in 0.167 degrees pixels. PRELES applied inventory-scaled information about forest structure at high resolution. There was little difference between the models in the results aggregated to national level. Temporal trends in annual GPPs were also parallel. Spatial differences could be partially related to differences in model input data on soils and leaf area. Differences were detected in the seasonal pattern of GPP but they contributed moderately to the annual totals. Both models predicted lower GPPs than MODIS, but MODIS still showed similar south north distribution of GPP. Convergent results for the national total GPP between JSBACH and PRELES, and those derived for comparison from the forest ghg-inventory, implied that modelled GPP estimates can be realistically up-scaled to larger region in spite of the fact that model calibrations may not originate from the study region, or that a limited number of sites was used in the calibration of a model.
  • Heinonen, Jussi S.; Bohrson, Wendy A.; Spera, Frank J.; Brown, Guy A.; Scruggs, Melissa A.; Adams, Jenna V. (2020)
    The Magma Chamber Simulator (MCS) is a thermodynamic model that computes the phase, thermal, and compositional evolution of a multiphase–multicomponent system of a Fractionally Crystallizing resident body of magma (i.e., melt ± solids ± fluid), linked wallrock that may either be assimilated as Anatectic melts or wholesale as Stoped blocks, and multiple Recharge reservoirs (RnASnFC system, where n is the number of user-selected recharge events). MCS calculations occur in two stages; the first utilizes mass and energy balance to produce thermodynamically constrained major element and phase equilibria information for an RnASnFC system; this tool is informally called MCS-PhaseEQ, and is described in a companion paper (Bohrson et al. 2020). The second stage of modeling, called MCS-Traces, calculates the RASFC evolution of up to 48 trace elements and seven radiogenic and one stable isotopic system (Sr, Nd, Hf, 3xPb, Os, and O) for the resident melt. In addition, trace element concentrations are calculated for bulk residual wallrock and each solid (± fluid) phase in the cumulate reservoir and residual wallrock. Input consists of (1) initial trace element concentrations and isotope ratios for the parental melt, wallrock, and recharge magmas/stoped wallrock blocks and (2) solid-melt and solid–fluid partition coefficients (optional temperature-dependence) for stable phases in the resident magma and residual wallrock. Output can be easily read and processed from tabulated worksheets. We provide trace element and isotopic results for the same example cases (FC, R2FC, AFC, S2FC, and R2AFC) presented in the companion paper. These simulations show that recharge processes can be difficult to recognize based on trace element data alone unless there is an independent reference frame of successive recharge events or if serial recharge magmas are sufficiently distinct in composition relative to the parental magma or magmas on the fractionation trend. In contrast, assimilation of wallrock is likely to have a notable effect on incompatible trace element and isotopic compositions of the contaminated resident melt. The magnitude of these effects depends on several factors incorporated into both stages of MCS calculations (e.g., phase equilibria, trace element partitioning, style of assimilation, and geochemistry of the starting materials). Significantly, the effects of assimilation can be counterintuitive and very different from simple scenarios (e.g., bulk mixing of magma and wallrock) that do not take account phase equilibria. Considerable caution should be practiced in ruling out potential assimilation scenarios in natural systems based upon simple geochemical “rules of thumb”. The lack of simplistic responses to open-system processes underscores the need for thermodynamical RASFC models that take into account mass and energy conservation. MCS-Traces provides an unprecedented and detailed framework for utilizing thermodynamic constraints and element partitioning to document trace element and isotopic evolution of igneous systems. Continued development of the Magma Chamber Simulator will focus on easier accessibility and additional capabilities that will allow the tool to better reproduce the documented natural complexities of open-system magmatic processes.
  • Bohrson, Wendy A.; Spera, Frank J.; Heinonen, Jussi S.; Brown, Guy A.; Scruggs, Melissa A.; Adams, Jenna V.; Takach, Marie K.; Zeff, Garrett; Suikkanen, Einari (2020)
    The Magma Chamber Simulator (MCS) is a thermodynamic tool for modeling the evolution of magmatic systems that are open with respect to assimilation of partial melts or stoped blocks, magma recharge + mixing, and fractional crystallization. MCS is available for both PC and Mac. In the MCS, the thermal, mass, and compositional evolution of a multicomponent-multiphase composite system of resident magma, wallrock, and recharge reservoirs is tracked by rigorous self-consistent thermodynamic modeling. A Recharge-Assimilation (Assimilated partial melt or Stoped blocks)-Fractional Crystallization (R(n)AS(n)FC;n(tot) The trace element and isotope MCS computational tool (MCS-Traces) is described in a separate contribution (part II).
  • Pulliainen, Jouni; Aurela, Mika; Laurila, Tuomas; Aalto, Tuula; Takala, Matias; Salminen, Miia; Kulmala, Markku; Barr, Alan; Heimann, Martin; Lindroth, Anders; Laaksonen, Ari; Derksen, Chris; Mäkelä, Annikki; Markkanen, Tiina; Lemmetyinen, Juha; Susiluoto, Jouni; Dengel, Sigrid; Mammarella, Ivan; Tuovinen, Juha-Pekka; Vesala, Timo (2017)
    We determine the annual timing of spring recovery from space-borne microwave radiometer observations across northern hemisphere boreal evergreen forests for 1979-2014. We find a trend of advanced spring recovery of carbon uptake for this period, with a total average shift of 8.1 d (2.3 d/decade). We use this trend to estimate the corresponding changes in gross primary production (GPP) by applying in situ carbon flux observations. Micrometeoro-logical CO2 measurements at four sites in northern Europe and North America indicate that such an advance in spring recovery would have increased the January-June GPP sum by 29 g.C.m(-2) [8.4 g.C.m(-2) (3.7%)/decade]. We find this sensitivity of the measured springtime GPP to the spring recovery to be in accordance with the corresponding sensitivity derived from simulations with a land ecosystem model coupled to a global circulation model. The model-predicted increase in springtime cumulative GPP was 0.035 Pg/decade [15.5 g.C.m(-2) (6.8%)/decade] for Eurasian forests and 0.017 Pg/decade for forests in North America [9.8 g.C.m(-2) (4.4%)/decade]. This change in the springtime sum of GPP related to the timing of spring snowmelt is quantified here for boreal evergreen forests.
  • Holmberg, Maria; Aalto, Tuula; Akujarvi, Anu; Arslan, Ali Nadir; Bergstrom, Irina; Bottcher, Kristin; Lahtinen, Ismo; Makela, Annikki; Markkanen, Tiina; Minunno, Francesco; Peltoniemi, Mikko; Rankinen, Katri; Vihervaara, Petteri; Forsius, Martin (2019)
    Forests regulate climate, as carbon, water and nutrient fluxes are modified by physiological processes of vegetation and soil. Forests also provide renewable raw material, food, and recreational possibilities. Rapid climate warming projected for the boreal zone may change the provision of these ecosystem services. We demonstrate model based estimates of present and future ecosystem services related to carbon cycling of boreal forests. The services were derived from biophysical variables calculated by two dynamic models. Future changes in the biophysical variables were driven by climate change scenarios obtained as results of a sample of global climate models downscaled for Finland, assuming three future pathways of radiative forcing. We introduce continuous monitoring on phenology to be used in model parametrization through a webcam network with automated image processing features. In our analysis, climate change impacts on key boreal forest ecosystem services are both beneficial and detrimental. Our results indicate an increase in annual forest growth of about 60% and an increase in annual carbon sink of roughly 40% from the reference period (1981-2010) to the end of the century. The vegetation active period was projected to start about 3 weeks earlier and end ten days later by the end of the century compared to currently. We found a risk for increasing drought, and a decrease in the number of soil frost days. Our results show a considerable uncertainty in future provision of boreal forest ecosystem services.
  • Loi, Silvia; Pitkänen, Joonas; Moustgaard, Heta; Myrskylä, Mikko; Martikainen, Pekka (2021)
    Although the children of first-generation immigrants tend to have better health than the native population, the health advantage of the children of immigrant families deteriorates over generations. It is, however, poorly understood where on the generational health assimilation spectrum children with one immigrant and one native parent (i.e., exogamous families) lie, to what extent family resources explain health assimilation, and whether the process of assimilation varies across health conditions. We seek to extend our understanding of the process of health assimilation by analyzing the physical and mental health of immigrant generations, assessing the role of exoga-mous family arrangements, and testing the contributions of family material and social resources to children’s outcomes. We use register-based longitudinal data on all children residing in Finland, born in 1986–2000, and alive in 2000; these data are free of report-ing bias and loss to follow-up. We estimate the risk of receiving inpatient and outpatient care for somatic conditions, psychopathological disorders, and injuries by immigrant generation status. Our results show evidence of a negative health assimilation process, with both first-and second-generation immigrant children having a higher prevalence of physical problems and particularly mental health problems than native children that is only partially explained by family resources. We find that the children of exogamous families are at especially high risk of developing psychopathological disorders. These results provide strong support for the hypothesis that children of exogamous families constitute a specific health risk group and that the impact on children’s health of family social and material resources seems to be secondary to other unobserved factors.
  • Lynch, Robert; Lummaa, Virpi; Panchanathan, Karthik; Middleton, Kevin; Rotkirch, Anna; Danielsbacka, Mirkka; O'Brien, David; Loehr, John (2019)
    Understanding how refugees integrate into host societies has broad implications for researchers interested in intergroup conflict and for governments concerned with promoting social cohesion. Using detailed records tracking the movements and life histories of Finnish evacuees during World War II, we find that evacuees who intermarry are more likely to be educated, work in professional occupations, marry someone higher in social status and remain in the host community. Evacuees who intermarry before the war have fewer children, whereas those who marry into their host community after the war have more children. These results indicate that life-history and assimilation outcomes depend on key differences between pre-war environments—when migrants are living in their own communities—and post-war environments—when migrants are living in the host community. Overall, this suggests that integration involves a trade-off between reproduction and status such that evacuees who integrate gain social status, whereas those who maintain stronger bonds with their natal communities have higher fertility. We discuss these results within the framework of social capital, intergroup conflict and life-history theory and suggest how they can inform our understanding of evolutionary adaptations that affect tribalism.
  • Zora, Hatice; Riad, Tomas; Ylinen, Sari; Csepe, Valeria (2021)
    Dealing with phonological variations is important for speech processing. This article addresses whether phonological variations introduced by assimilatory processes are compensated for at the pre-lexical or lexical level, and whether the nature of variation and the phonological context influence this process. To this end, Swedish nasal regressive place assimilation was investigated using the mismatch negativity (MMN) component. In nasal regressive assimilation, the coronal nasal assimilates to the place of articulation of a following segment, most clearly with a velar or labial place of articulation, as in utan mej "without me" > [MODIFIER LETTER TRIANGULAR COLONtam mejMODIFIER LETTER TRIANGULAR COLON]. In a passive auditory oddball paradigm, 15 Swedish speakers were presented with Swedish phrases with attested and unattested phonological variations and contexts for nasal assimilation. Attested variations - a coronal-to-labial change as in utan "without" > [MODIFIER LETTER TRIANGULAR COLONtam] - were contrasted with unattested variations - a labial-to-coronal change as in utom "except" > *[MODIFIER LETTER TRIANGULAR COLONtLATIN SMALL LETTER OPEN On] - in appropriate and inappropriate contexts created by mej "me" [mejMODIFIER LETTER TRIANGULAR COLON] and dej "you" [dejMODIFIER LETTER TRIANGULAR COLON]. Given that the MMN amplitude depends on the degree of variation between two stimuli, the MMN responses were expected to indicate to what extent the distance between variants was tolerated by the perceptual system. Since the MMN response reflects not only low-level acoustic processing but also higher-level linguistic processes, the results were predicted to indicate whether listeners process assimilation at the pre-lexical and lexical levels. The results indicated no significant interactions across variations, suggesting that variations in phonological forms do not incur any cost in lexical retrieval; hence such variation is compensated for at the lexical level. However, since the MMN response reached significance only for a labial-to-coronal change in a labial context and for a coronal-to-labial change in a coronal context, the compensation might have been influenced by the nature of variation and the phonological context. It is therefore concluded that while assimilation is compensated for at the lexical level, there is also some influence from pre-lexical processing. The present results reveal not only signal-based perception of phonological units, but also higher-level lexical processing, and are thus able to reconcile the bottom-up and top-down models of speech processing.
  • Jokinen, Kari; Salovaara, Anna-Kaisa Johanna; Wasonga, Daniel; Edelmann, Minnamari; Simpura, Ilkka; Mäkelä, Pirjo (2022)
    Leafy vegetables like lettuce (Lactuca sativa L.) naturally have high nitrate content and the European Commission has set maximum level for nitrate in lettuce. Glycinebetaine is an organic osmolyte alleviating plant stress, but its role in leaf nitrate accumulation remains unknown. The uptake of glycinebetaine by lettuce roots, and its potential to regulate lettuce nitrate content and improve plant quality were investigated. Two hydroponic lettuce experiments were conducted with different glycinebetaine application rates (Exp1 : 0, 1, 7.5, and 15 mM; Exp2: 0, 1 + 1 + 1, 1 + 10, and 4 mM). Plants were analyzed at varying time points. Root application resulted in glycinebetaine uptake and translocation to the leaves. Glycinebetaine concentrations > 7.5 mM reduced leaf nitrate up to 40% and increased leaf dry matter content. Glycinebetaine showed a positive effect on leaf mineral and amino acid composition. Thus, glycinebetaine could be a novel strategy to reduce the nitrate content in hydroponic lettuce.
  • Loustau, Denis; Altimir, Nuria; Barbaste, Mireille; Gielen, Bert; Maranon Jimenez, Sara; Klumpp, Katja; Linder, Sune; Matteucci, Giorgio; Merbold, Lutz; Op de Beek, Marteen; Soule, Patrice; Thimonier, Anne; Vincke, Caroline; Waldner, Peter (2018)
    The nutritional status of plant canopies in terms of nutrients (C, N, P, K, Ca, Mg, Mn, Fe, Cu, Zn) exerts a strong influence on the carbon cycle and energy balance of terrestrial ecosystems. Therefore, in order to account for the spatial and temporal variations in nutritional status of the plant species composing the canopy, we detail the methodology applied to achieve consistent time-series of leaf mass to area ratio and nutrient content of the foliage within the footprint of the Integrated Carbon Observation System Ecosystem stations. The guidelines and definitions apply to most terrestrial ecosystems.
  • Pastorello, Gilberto; Trotta, Carlo; Canfora, Eleonora; Chu, Housen; Christianson, Danielle; Cheah, You-Wei; Poindexter, Cristina; Chen, Jiquan; Elbashandy, Abdelrahman; Humphrey, Marty; Isaac, Peter; Polidori, Diego; Ribeca, Alessio; van Ingen, Catharine; Zhang, Leiming; Amiro, Brian; Ammann, Christof; Arain, M. Altaf; Ardo, Jonas; Arkebauer, Timothy; Arndt, Stefan K.; Arriga, Nicola; Aubinet, Marc; Aurela, Mika; Baldocchi, Dennis; Barr, Alan; Beamesderfer, Eric; Marchesini, Luca Belelli; Bergeron, Onil; Beringer, Jason; Bernhofer, Christian; Berveiller, Daniel; Billesbach, Dave; Black, Thomas Andrew; Blanken, Peter D.; Bohrer, Gil; Boike, Julia; Bolstad, Paul V.; Bonal, Damien; Bonnefond, Jean-Marc; Bowling, David R.; Bracho, Rosvel; Brodeur, Jason; Bruemmer, Christian; Buchmann, Nina; Burban, Benoit; Burns, Sean P.; Buysse, Pauline; Cale, Peter; Cavagna, Mauro; Cellier, Pierre; Chen, Shiping; Chini, Isaac; Christensen, Torben R.; Cleverly, James; Collalti, Alessio; Consalvo, Claudia; Cook, Bruce D.; Cook, David; Coursolle, Carole; Cremonese, Edoardo; Curtis, Peter S.; D'Andrea, Ettore; da Rocha, Humberto; Dai, Xiaoqin; Davis, Kenneth J.; De Cinti, Bruno; de Grandcourt, Agnes; De Ligne, Anne; De Oliveira, Raimundo C.; Delpierre, Nicolas; Desai, Ankur R.; Di Bella, Carlos Marcelo; di Tommasi, Paul; Dolman, Han; Domingo, Francisco; Dong, Gang; Dore, Sabina; Duce, Pierpaolo; Dufrene, Eric; Dunn, Allison; Dusek, Jiri; Eamus, Derek; Eichelmann, Uwe; ElKhidir, Hatim Abdalla M.; Eugster, Werner; Ewenz, Cacilia M.; Ewers, Brent; Famulari, Daniela; Fares, Silvano; Feigenwinter, Iris; Feitz, Andrew; Fensholt, Rasmus; Filippa, Gianluca; Fischer, Marc; Frank, John; Galvagno, Marta; Gharun, Mana; Gianelle, Damiano; Gielen, Bert; Gioli, Beniamino; Gitelson, Anatoly; Goded, Ignacio; Goeckede, Mathias; Goldstein, Allen H.; Gough, Christopher M.; Goulden, Michael L.; Graf, Alexander; Griebel, Anne; Gruening, Carsten; Gruenwald, Thomas; Hammerle, Albin; Han, Shijie; Han, Xingguo; Hansen, Birger Ulf; Hanson, Chad; Hatakka, Juha; He, Yongtao; Hehn, Markus; Heinesch, Bernard; Hinko-Najera, Nina; Hoertnagl, Lukas; Hutley, Lindsay; Ibrom, Andreas; Ikawa, Hiroki; Jackowicz-Korczynski, Marcin; Janous, Dalibor; Jans, Wilma; Jassal, Rachhpal; Jiang, Shicheng; Kato, Tomomichi; Khomik, Myroslava; Klatt, Janina; Knohl, Alexander; Knox, Sara; Kobayashi, Hideki; Koerber, Georgia; Kolle, Olaf; Kosugi, Yoshiko; Kotani, Ayumi; Kowalski, Andrew; Kruijt, Bart; Kurbatova, Julia; Kutsch, Werner L.; Kwon, Hyojung; Launiainen, Samuli; Laurila, Tuomas; Law, Bev; Leuning, Ray; Li, Yingnian; Liddell, Michael; Limousin, Jean-Marc; Lion, Marryanna; Liska, Adam J.; Lohila, Annalea; Lopez-Ballesteros, Ana; Lopez-Blanco, Efren; Loubet, Benjamin; Loustau, Denis; Lucas-Moffat, Antje; Lueers, Johannes; Ma, Siyan; Macfarlane, Craig; Magliulo, Vincenzo; Maier, Regine; Mammarella, Ivan; Manca, Giovanni; Marcolla, Barbara; Margolis, Hank A.; Marras, Serena; Massman, William; Mastepanov, Mikhail; Matamala, Roser; Matthes, Jaclyn Hatala; Mazzenga, Francesco; McCaughey, Harry; McHugh, Ian; McMillan, Andrew M. S.; Merbold, Lutz; Meyer, Wayne; Meyers, Tilden; Miller, Scott D.; Minerbi, Stefano; Moderow, Uta; Monson, Russell K.; Montagnani, Leonardo; Moore, Caitlin E.; Moors, Eddy; Moreaux, Virginie; Moureaux, Christine; Munger, J. William; Nakai, Taro; Neirynck, Johan; Nesic, Zoran; Nicolini, Giacomo; Noormets, Asko; Northwood, Matthew; Nosetto, Marcelo; Nouvellon, Yann; Novick, Kimberly; Oechel, Walter; Olesen, Jorgen Eivind; Ourcival, Jean-Marc; Papuga, Shirley A.; Parmentier, Frans-Jan; Paul-Limoges, Eugenie; Pavelka, Marian; Peichl, Matthias; Pendall, Elise; Phillips, Richard P.; Pilegaard, Kim; Pirk, Norbert; Posse, Gabriela; Powell, Thomas; Prasse, Heiko; Prober, Suzanne M.; Rambal, Serge; Rannik, Ullar; Raz-Yaseef, Naama; Reed, David; de Dios, Victor Resco; Restrepo-Coupe, Natalia; Reverter, Borja R.; Roland, Marilyn; Sabbatini, Simone; Sachs, Torsten; Saleska, Scott R.; Sanchez-Canete, Enrique P.; Sanchez-Mejia, Zulia M.; Schmid, Hans Peter; Schmidt, Marius; Schneider, Karl; Schrader, Frederik; Schroder, Ivan; Scott, Russell L.; Sedlak, Pavel; Serrano-Ortiz, Penelope; Shao, Changliang; Shi, Peili; Shironya, Ivan; Siebicke, Lukas; Sigut, Ladislav; Silberstein, Richard; Sirca, Costantino; Spano, Donatella; Steinbrecher, Rainer; Stevens, Robert M.; Sturtevant, Cove; Suyker, Andy; Tagesson, Torbern; Takanashi, Satoru; Tang, Yanhong; Tapper, Nigel; Thom, Jonathan; Tiedemann, Frank; Tomassucci, Michele; Tuovinen, Juha-Pekka; Urbanski, Shawn; Valentini, Riccardo; van der Molen, Michiel; van Gorsel, Eva; van Huissteden, Ko; Varlagin, Andrej; Verfaillie, Joseph; Vesala, Timo; Vincke, Caroline; Vitale, Domenico; Vygodskaya, Natalia; Walker, Jeffrey P.; Walter-Shea, Elizabeth; Wang, Huimin; Weber, Robin; Westermann, Sebastian; Wille, Christian; Wofsy, Steven; Wohlfahrt, Georg; Wolf, Sebastian; Woodgate, William; Li, Yuelin; Zampedri, Roberto; Zhang, Junhui; Zhou, Guoyi; Zona, Donatella; Agarwal, Deb; Biraud, Sebastien; Torn, Margaret; Papale, Dario (2020)
    The FLUXNET2015 dataset provides ecosystem-scale data on CO2, water, and energy exchange between the biosphere and the atmosphere, and other meteorological and biological measurements, from 212 sites around the globe (over 1500 site-years, up to and including year 2014). These sites, independently managed and operated, voluntarily contributed their data to create global datasets. Data were quality controlled and processed using uniform methods, to improve consistency and intercomparability across sites. The dataset is already being used in a number of applications, including ecophysiology studies, remote sensing studies, and development of ecosystem and Earth system models. FLUXNET2015 includes derived-data products, such as gap-filled time series, ecosystem respiration and photosynthetic uptake estimates, estimation of uncertainties, and metadata about the measurements, presented for the first time in this paper. In addition, 206 of these sites are for the first time distributed under a Creative Commons (CC-BY 4.0) license. This paper details this enhanced dataset and the processing methods, now made available as open-source codes, making the dataset more accessible, transparent, and reproducible.