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Upscaling Northern Peatland CO2 Fluxes Using Satellite Remote Sensing Data

Sofia Junttila, Julia Kelly, Natascha Kljun, Mika Aurela, Leif Klemedtsson, Annalea Lohila, Mats B. Nilsson, Janne Rinne, Eeva-Stiina Tuittila, Patrik Vestin, Per Weslien, Lars Eklundh
2021 Remote Sensing  
Peatlands play an important role in the global carbon cycle as they contain a large soil carbon stock. However, current climate change could potentially shift peatlands from being carbon sinks to carbon sources. Remote sensing methods provide an opportunity to monitor carbon dioxide (CO2) exchange in peatland ecosystems at large scales under these changing conditions. In this study, we developed empirical models of the CO2 balance (net ecosystem exchange, NEE), gross primary production (GPP),
more » ... d ecosystem respiration (ER) that could be used for upscaling CO2 fluxes with remotely sensed data. Two to three years of eddy covariance (EC) data from five peatlands in Sweden and Finland were compared to modelled NEE, GPP and ER based on vegetation indices from 10 m resolution Sentinel-2 MSI and land surface temperature from 1 km resolution MODIS data. To ensure a precise match between the EC data and the Sentinel-2 observations, a footprint model was applied to derive footprint-weighted daily means of the vegetation indices. Average model parameters for all sites were acquired with a leave-one-out-cross-validation procedure. Both the GPP and the ER models gave high agreement with the EC-derived fluxes (R2 = 0.70 and 0.56, NRMSE = 14% and 15%, respectively). The performance of the NEE model was weaker (average R2 = 0.36 and NRMSE = 13%). Our findings demonstrate that using optical and thermal satellite sensor data is a feasible method for upscaling the GPP and ER of northern boreal peatlands, although further studies are needed to investigate the sources of the unexplained spatial and temporal variation of the CO2 fluxes.
doi:10.3390/rs13040818 fatcat:nnc4mmkax5ahzbkhyov5tys2ue

Modelling Daily Gross Primary Productivity with Sentinel-2 Data in the Nordic Region–Comparison with Data from MODIS

Zhanzhang Cai, Sofia Junttila, Jutta Holst, Hongxiao Jin, Jonas Ardö, Andreas Ibrom, Matthias Peichl, Meelis Mölder, Per Jönsson, Janne Rinne, Maria Karamihalaki, Lars Eklundh
2021 Remote Sensing  
The high-resolution Sentinel-2 data potentially enable the estimation of gross primary productivity (GPP) at finer spatial resolution by better capturing the spatial variation in a heterogeneous landscapes. This study investigates the potential of 10 m resolution reflectance from the Sentinel-2 Multispectral Instrument to improve the accuracy of GPP estimation across Nordic vegetation types, compared with the 250 m and 500 m resolution reflectance from the Moderate Resolution Imaging
more » ... ometer (MODIS). We applied linear regression models with inputs of two-band enhanced vegetation index (EVI2) derived from Sentinel-2 and MODIS reflectance, respectively, together with various environmental drivers to estimate daily GPP at eight Nordic eddy covariance (EC) flux tower sites. Compared with the GPP from EC measurements, the accuracies of modelled GPP were generally high (R2 = 0.84 for Sentinel-2; R2 = 0.83 for MODIS), and the differences between Sentinel-2 and MODIS were minimal. This demonstrates the general consistency in GPP estimates based on the two satellite sensor systems at the Nordic regional scale. On the other hand, the model accuracy did not improve by using the higher spatial-resolution Sentinel-2 data. More analyses of different model formulations, more tests of remotely sensed indices and biophysical parameters, and analyses across a wider range of geographical locations and times will be required to achieve improved GPP estimations from Sentinel-2 satellite data.
doi:10.3390/rs13030469 fatcat:szlyd6de4vfolkrmj63c3uioue

Suomalais-Ugrilaisen Seuran vuosikertomus ja tilinpäätös vuodelta 2019

Susanna Virtanen
2021 Suomalais-Ugrilaisen Seuran Aikakauskirja  
Sofia Björklöf & Santra Jantunen (toim.): Multilingual Finnic -Language contact and change.  ...  Kotisivuja ovat kuluneena vuonna ylläpitäneet tuntityöläinen Katriina Ketola, korkeakouluharjoittelija Elli Virmasalo sekä kustannustoimittaja Anna Kurvinen. • 18.1.2019 FT Santeri Junttila (HY) & dos.  ... 
doi:10.33340/susa.117849 fatcat:p7yc5mbh6zcuhdem3i6iia4nwm

Page 4875 of Psychological Abstracts Vol. 89, Issue 12 [page]

2002 Psychological Abstracts  
W., 3633 Kerzmann, Anne, 35702 Keshavan, Matcheri. 36118 Kesidou, Sofia, 37583 Keskinen, E., 37865 Kesler, Frederick C., 36( Kesner, Raymond P., 3 Kessels, Roy P.  ...  ., 37014 Jung, Ji Hyun, 36135 Jung, Han Young, 36731 Junge, Benjamin, 36838 Junge, Candace, 35469 Junghanns, Klaus, 34980, 36644 Junkers, Gabriele, 36956 Junttila, Mikko A., 35002 Jureidini, J., 36188  ... 

Resistance to freezing in three Eucalyptus globulus Labill subspecies

Priscila Moraga S., Rene Escobar, Sofia Valenzuela A.
2006 Electronic Journal of Biotechnology  
Enhancement of freezing tolerance is also accompanied by accumulation of compatible solutes such as soluble sugars and amino acids (Palonen and Junttila, 1999) .  ... 
doi:10.2225/vol9-issue3-fulltext-24 fatcat:gxnhl2ftlrauzdrvlnulx42cry

COMPARATIVE ANALYSIS OF THE EXPERIENCE OF LONELINESS BETWEEN BULGARIANS AND RUSSIANS

Nataliya Alexandrova, Liliya Babakova, Inna Murtazina, Olga Strizhitskaya, Marina Petrash, Yuliya Chankova
2021 Proceedings of CBU in Social Sciences  
Weiss (1973) and Junttila et al. (2013) offer two main dimensions of loneliness -social and emotional loneliness.  ...  13.503 7.3063 25.79 15.926 Widower 14.33 7.3219 27.949 16.342 Marginal Mean by factor "country", "marital status", "emotional loneliness" and "romantic loneliness" International Business School, Sofia  ... 
doi:10.12955/pss.v2.194 fatcat:dljna2vggfhqbprzmysuvbdyme

Kansainvälinen, suomalainen vai venäläinen?

Ksenia Eskola
2015 Sananjalka  
Heikkinen > Heikinen, Junttila > Juntila, Olkkonen > Olkonen (Korpivaara 2005, 46) .  ...  Sofia lausutaan suomeksi paino ensimmäisellä tavulla, kun venäjäksi taas toisella ja nimen loppu ääntyy ja:llisena: Sofija.  ... 
doi:10.30673/sja.86738 fatcat:3v6bmqpworbo5iwi3defkiprie

Page 1945 of Mathematical Reviews Vol. , Issue Subject Index [page]

Mathematical Reviews  
(English summary) (see 2002c:68009) Guerra, Sofia Composition of default specifications.  ...  Junttila, Tommi A. (with Niemela, Ikka) Towards an efficient tableau method for Boolean circuit satisfiability checking. (English summary) Jutla, Charanjit S. see Emerson, E.  ... 

Page 3693 of Bibliography of Agriculture. Annual Cumulative Indexes Vol. 51, Issue [page]

Bibliography of Agriculture. Annual Cumulative Indexes  
411876 Juniper, B. 404603 Junker, A. 439483 Junker, B. 456033, 456295 Junnila, William A. 415579 Junod, P. 469848 Junqueira, O. ms 393230 Juntarashote, Kungwan 426127, 434796 434839 Juntti, N. 475239 Junttila  ...  A. 380111 Kaboret, Y.Y. 385046 Kabulov, A.D. 397169 Kabuswe, Moses Lawrence, 405992 Kacabova, P. 412929 Kacew, S. 436164 Kachanoski, R.G. 413235, 413387 Kachanova, Sofia Pavlovna. 793 391999, Kachekhina  ... 

Gordon Research Conferences

2015 Science  
Sofia Orre-Gordon / Allard Cose) • Essential Oils and Other VOCs in Biocontrol and the Industry (Mark Lange / Toby Bruce / Ravinder Kohli / Elena Stashenko) • Plant VOC Metabolism, Biosynthetic Diversity  ...  Lanzavecchia, Michel Nussenzweig / Erica Ollmann Saphire / Louis Weiner / Antonio Lanzavecchia / Michel Nussenzweig) • Unique Therapeutic Vistas in Antibody Engineering: Bispecifics (Paul Carter / Teemu Junttila  ... 
doi:10.1126/science.349.6255.1554 fatcat:7xeslqqaevbklocrpdfwawxo2q

Resistance to freezing in three Eucalyptus globulus Labill subspecies

Priscila Moraga, René Escobar, Sofía Valenzuela
2006 Electronic Journal of Biotechnology   unpublished
Enhancement of freezing tolerance is also accompanied by accumulation of compatible solutes such as soluble sugars and amino acids (Palonen and Junttila, 1999) .  ... 
fatcat:nifduqk3bnephit2ey4iqblfqi

Macrophage Heterogeneity and Plasticity: Impact of Macrophage Biomarkers on Atherosclerosis

Joselyn Rojas, Juan Salazar, María Sofía Martínez, Jim Palmar, Jordan Bautista, Mervin Chávez-Castillo, Alexis Gómez, Valmore Bermúdez
2015 Scientifica  
Junttila, R. P. Bourette, L. R. Rohrschneider, and O.  ... 
doi:10.1155/2015/851252 pmid:26491604 pmcid:PMC4600540 fatcat:imfs3gyz6nflrn2hc3i4wtm6si

Circadian Clock Components Regulate Entry and Affect Exit of Seasonal Dormancy as Well as Winter Hardiness in Populus Trees

C. Ibanez, I. Kozarewa, M. Johansson, E. Ogren, A. Rohde, M. E. Eriksson
2010 Plant Physiology  
ACKNOWLEDGMENTS We are grateful to the staff of the transgenic facility and green house for help with obtaining and care of transgenic plants, and Sofia Ö sterberg and Ana Sánchez García for technical  ...  ., cease growing and set buds when daylength is shortened below a critical value, the critical daylength (CDL; Junttila, 1982; Howe et al., 2003; Bö hlenius et al., 2006) .  ... 
doi:10.1104/pp.110.158220 pmid:20530613 pmcid:PMC2923903 fatcat:s5broica4bauto5y44aiub5a4m

CIP2A interacts with TopBP1 and drives basal-like breast cancer tumorigenesis

Anni Laine, Srikar G. Nagelli, Caroline Farrington, Umar Butt, Anna N. Cvrljevic, Julia P. Vainonen, Femke M. Feringa, Tove J. Grönroos, Prson Gautam, Sofia Khan, Harri Sihto, Xi Qiao (+12 others)
2021 Cancer Research  
Khanna A, Böckelman C, Hemmes A, Junttila MR, Wiksten JP, Lundin M, et al. 700 MYC-dependent regulation and prognostic role of CIP2A in gastric cancer. J Natl 701 Cancer Inst 2009;101:793-805 702 34.  ... 
doi:10.1158/0008-5472.can-20-3651 pmid:34145035 pmcid:PMC8373817 fatcat:rsi7r3wnaffvfiaspzzycpgbxm

Mutual contacts and lexical relations among the Finnic varieties of western Ingria and northeastern Estonia

Sofia Björklöf
2019 Uralica Helsingiensia  
‹http:// kaino.kotus.fi/sanat/vepsa/› Itämerensuomen varieteet tien keskinäiset kontak tit ja sanastolliset suhteet Länsi-Inkerissä ja Koillis-Virossa Sofia Björklöf  ...  Constructing hypotheses on language contacts in this way but not providing substantial evidence for them is, in fact, common to Ariste (see Junttila 2015: 26). and Finnish, followed by possible variants  ... 
doi:10.33341/uh.85034 fatcat:molf6xapafcw7dnngfxlm33upu
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