Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
2021
Authors
Tor Myking Jade Phillips Enrico Sturaro Kjersti Bakkebø Fjellstad Nina Svartedal Hojka Kraigher Marjana Westergren Nigel Maxted Magda Bou Dagher Kharrat Silvia Perez-EsponaAbstract
No abstract has been registered
Authors
Peter Horvath Hui Tang Rune Halvorsen Frode Stordal Lena M. Tallaksen Terje Koren Berntsen Anders BrynAbstract
Vegetation is an important component in global ecosystems, affecting the physical, hydrological and biogeochemical properties of the land surface. Accordingly, the way vegetation is parameterized strongly influences predictions of future climate by Earth system models. To capture future spatial and temporal changes in vegetation cover and its feedbacks to the climate system, dynamic global vegetation models (DGVMs) are included as important components of land surface models. Variation in the predicted vegetation cover from DGVMs therefore has large impacts on modelled radiative and non-radiative properties, especially over high-latitude regions. DGVMs are mostly evaluated by remotely sensed products and less often by other vegetation products or by in situ field observations. In this study, we evaluate the performance of three methods for spatial representation of present-day vegetation cover with respect to prediction of plant functional type (PFT) profiles – one based upon distribution models (DMs), one that uses a remote sensing (RS) dataset and a DGVM (CLM4.5BGCDV; Community Land Model 4.5 Bio-Geo-Chemical cycles and Dynamical Vegetation). While DGVMs predict PFT profiles based on physiological and ecological processes, a DM relies on statistical correlations between a set of predictors and the modelled target, and the RS dataset is based on classification of spectral reflectance patterns of satellite images. PFT profiles obtained from an independently collected field-based vegetation dataset from Norway were used for the evaluation. We found that RS-based PFT profiles matched the reference dataset best, closely followed by DM, whereas predictions from DGVMs often deviated strongly from the reference. DGVM predictions overestimated the area covered by boreal needleleaf evergreen trees and bare ground at the expense of boreal broadleaf deciduous trees and shrubs. Based on environmental predictors identified by DM as important, three new environmental variables (e.g. minimum temperature in May, snow water equivalent in October and precipitation seasonality) were selected as the threshold for the establishment of these high-latitude PFTs. We performed a series of sensitivity experiments to investigate if these thresholds improve the performance of the DGVM method. Based on our results, we suggest implementation of one of these novel PFT-specific thresholds (i.e. precipitation seasonality) in the DGVM method. The results highlight the potential of using PFT-specific thresholds obtained by DM in development of DGVMs in broader regions. Also, we emphasize the potential of establishing DMs as a reliable method for providing PFT distributions for evaluation of DGVMs alongside RS.
Abstract
Distribution modeling methods are used to provide occurrence probability surfaces for modeled targets. While most often used for modeling species, distribution modeling methods can also be applied to vegetation types. However, surfaces provided by distribution modeling need to be transformed into classified wall-to-wall maps of vegetation types to be useful for practical purposes, such as nature management and environmental planning. The paper compares the performance of three methods for assembling predictions for multiple vegetation types, modeled individually, into a wall-to-wall map. The authors used grid-cell based probability surfaces from distribution models of 31 vegetation types to test the three assembly methods. The first, a probability-based method, selected for each grid cell the vegetation type with the highest predicted probability of occurrence in that cell. The second, a performance-based method, assigned the vegetation types, ordered from high to low model performance, to a fraction of the grid cells given by the vegetation type’s prevalence in the study area. The third, a prevalence-based method, differed from the performance-based method by assigning vegetation types in the order from low to high prevalence. Thus the assembly methods worked in two principally different ways: the probability-based method assigned vegetation types to grid cells in a cell-by-cell manner, and both the performance-based method and prevalence-based method assigned them in a type-by-type manner. All methods were evaluated by use of reference data collected in the field, more or less independently of the data used to parameterize the vegetation-type models. Quantity, allocation, and total disagreement, as well as proportional dissimilarity metrics, were used for evaluation of assembly methods. Overlay analysis showed 38.1% agreement between all three assembly methods. The probability-based method had the lowest total disagreement with, and proportional dissimilarity from, the reference datasets, but the differences between the three methods were small. The three assembly methods differed strongly with respect to the distribution of the total disagreement on its quantity and allocation components: the cell-by-cell assignment method strongly favored allocation disagreement and the type-by-type methods strongly favored quantity disagreement. The probability-based method best reproduced the general pattern of variation across the study area, but at the cost of many rare vegetation types, which were left out of the assembled map. By contrast, the prevalence-based and performance-based methods represented vegetation types in accordance with nationwide area statistics. The results show that maps of vegetation types with wall-to-wall coverage can be assembled from individual distribution models with a quality acceptable for indicative purposes, but all the three tested methods currently also have shortcomings. The results also indicate specific points in the methodology for map assembly that may be improved. area frame survey, assembly strategies, distribution modeling, spatial probabilities, vegetation mapping, vegetation types
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Authors
Ulrike BayrAbstract
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Authors
Idoia Biurrun Remigiusz Pielech Iwona Dembicz François Gillet Łukasz Kozub Corrado Marcenó Triin Reitalu Koenraad Van Meerbeek Riccardo Guarino Milan Chytrý Robin J Pakeman Zdenka Preislerová Irena Axmanová Sabina Burrascano Sándor Bartha Steffen Boch Hans Henrik Bruun Timo Conradi Pieter De Frenne Franz Essl Goffredo Filibeck Michal Hájek Borja Jiménez-Alfaro Anna Kuzemko Zsolt Molnár Meelis Pärtel Ricarda Pätsch Honor C. Prentice Jan Roleček Laura M. E. Sutcliffe Massimo Terzi Manuela Winkler Jianshuang Wu Svetlana Acíc Alicia T.R. Acosta Elias Afif Munemitsu Akasaka Juha M. Alatalo Michele Aleffi Alla Aleksanyan Arshad Ali Iva Apostolova Parvaneh Ashouri Zoltán Bátori Esther Baumann Thomas Becker Elena Belonovskaya José Luis Benito Alonso Asun Berastegi Ariel Bergamini Kuber Prasad Bhatta Ilaria Bonini Marc-Olivier Büchler Vasyl Budzhak Alvaro Bueno Fabrizio Buldrini Juan Antonio Campos Laura Cancellieri Marta Carboni Tobias Ceulemans Alessandro Chiarucci Cristina Chocarro Luisa Conti Anna Mária Csergő Beata Cykowska-Marzencka Marta Czarniecka-Wiera Marta Czarnocka-Cieciura Patryk Czortek Jiří Danihelka Francesco de Bello Balázs Deák László Demeter Lei Deng Martin Diekmann Jiří Doležal Christian Dolnik Pavel Dřevojan Cecilia Duprè Klaus Ecker Hamid Ejtehadi Brigitta Erschbamer Javier Etayo Jonathan Etzold Tünde Farkas Mohammad Farzam George Fayvush Maria Rosa Fernández Calzado Manfred Finckh Wendy Fjellstad Georgios Fotiadis Daniel García-Magro Itziar García-Mijangos Rosario G. Gavilán Markus Germany Sahar Ghafari Gian Pietro Giusso del Galdo John Arvid Grytnes Behlul Güler Alba Gutiérrez-Girón Aveliina Helm Mercedes Herrera Elisabeth M. Hüllbusch Nele Ingerpuu Annika Jagerbrand Ute Jandt Monika Janišová Philippe Jeanneret Florian Jeltsch Kai Jensen Anke Jentsch Zygmunt Kącki Kaoru Kakinuma Jutta Kapfer Mansoureh Kargar András Kelemen Kathrin Kiehl Philipp Kirschner Asuka Koyama Nancy Langer Lorenzo Lazzaro Jan Lepš Ching-Feng Li Frank Yonghong Li Diego Liendo Regina Lindborg Swantje Löbel Angela Lomba Zdeňka Lososová Pavel Lustyk Arantzazu L. Luzuriaga Wenhong Ma Simona Maccherini Martin Magnes Marek Malicki Michael Manthey Constantin Mardari Felix May Helmut Mayrhofer Eliane S. Meier Farshid Memariani Kristina Merunková Ottar Michelsen Joaquín Molero Mesa Halime Moradi Ivan Moysiyenko Michele Mugnai Alireza Naqinezhad Rayna Natcheva Josep M. Ninot Marcin Nobis Jalil Noroozi Arkadiusz Nowak Vladimir Onipchenko Salza Palpurina Harald Pauli Hristo Pedashenko Christian Pedersen Robert K. Peet Aaron Pérez-Haase Jan Peters Nataša Pipenbaher Chrisoula Pirini Eulàlia Pladevall-Izard Zuzana Plesková Giovanna Potenza Soroor Rahmanian Maria Pilar Rodríguez-Rojo Vladimir Ronkin Leonardo Rosati Eszter Ruprecht Solvita Rusina Marko Sabovljević Anvar Sanaei Ana M. Sánchez Francesco Santi Galina Savchenko Maria Teresa Sebastia Dariia Shyriaieva Vasco Silva Sonja Skornik Eva Šmerdová Judit Sonkoly Marta Gaia Sperandii Monika Staniaszek-Kik Carly Stevens Simon Stifter Sigrid Suchrow Grzegorz Swacha Sebastian Świerszcz Amir Talebi Balázs Teleki Lubomír Tichý Csaba Tölgyesi Marta Torca Péter Török Nadezda Tsarevskaya Ioannis Tsiripidis Ingrid Turisová Atushi Ushimaru Orsolya Valkó Carmen Van Mechelen Thomas Vanneste Iuliia Vasheniak Kiril Vassilev Daniele Viciani Luis Villar Risto Virtanen Ivana Vitasović-Kosić András Vojtkó Denys Vynokurov Emelie Waldén Yun Wang Frank Weiser Lu Wen Karsten Wesche Hannah White Stefan Widmer Sebastian Wolfrum Anna Wróbel Zuoqiang Yuan David Zelený Liqing Zhao Jürgen DenglerAbstract
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Authors
Thyra Sophie Hofmann Günay Bayramov Thomas Wagner Anneli Karlsson Wendy Fjellstad Sebastian EiterAbstract
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Authors
Nicholas Clarke Lars Pødenphant Kiær O. Janne Kjønaas Teresa Gómez de la Bárcena Lars Vesterdal Inge Stupak Leena Finér Staffan Jacobson Kestutis Armolaitis Dagnija Lazdina Helena Marta Stefánsdóttir Bjarni D. SigurdssonAbstract
No abstract has been registered