Staff Publications

Staff Publications

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    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

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Framing the concept of satellite remote sensing essential biodiversity variables: challenges and future directions
Pettorelli, Nathalie ; Wegmann, Martin ; Skidmore, Andrew ; Mücher, Sander ; Dawson, Terence P. ; Fernandez, Miguel ; Lucas, Richard ; Schaepman, Michael E. ; Wang, Tiejun ; O'Connor, Brian ; Jongman, Robert H.G. ; Kempeneers, Pieter ; Sonnenschein, Ruth ; Leidner, Allison K. ; Böhm, Monika ; He, Kate S. ; Nagendra, Harini ; Dubois, Grégoire ; Fatoyinbo, Temilola ; Hansen, Matthew C. ; Paganini, Marc ; Klerk, Helen M. De; Asner, Gregory P. ; Kerr, Jeremy T. ; Estes, Anna B. ; Schmeller, Dirk S. ; Heiden, Uta ; Rocchini, Duccio ; Pereira, Henrique M. ; Turak, Eren ; Fernandez, Nestor ; Lausch, Angela ; Cho, Moses A. ; Alcaraz-segura, Domingo ; Mcgeoch, Mélodie A. ; Turner, Woody ; Mueller, Andreas ; St-Louis, Véronique ; Penner, Johannes ; Vihervaara, Petteri ; Belward, Alan ; Reyers, Belinda ; Geller, Gary N. - \ 2016
Remote Sensing in Ecology and Conservation 2 (2016)3. - ISSN 2056-3485 - p. 122 - 131.
Although satellite-based variables have for long been expected to be key components to a unified and global biodiversity monitoring strategy, a definitive and agreed list of these variables still remains elusive. The growth of interest in biodiversity variables observable from space has been partly underpinned by the development of the essential biodiversity variable (EBV) framework by the Group on Earth Observations – Biodiversity Observation Network, which itself was guided by the process of identifying essential climate variables. This contribution aims to advance the development of a global biodiversity monitoring strategy by updating the previously published definition of EBV, providing a definition of satellite remote sensing (SRS) EBVs and introducing a set of principles that are believed to be necessary if ecologists and space agencies are to agree on a list of EBVs that can be routinely monitored from space. Progress toward the identification of SRS-EBVs will require a clear understanding of what makes a biodiversity variable essential, as well as agreement on who the users of the SRS-EBVs are. Technological and algorithmic developments are rapidly expanding the set of opportunities for SRS in monitoring biodiversity, and so the list of SRS-EBVs is likely to evolve over time. This means that a clear and common platform for data providers, ecologists, environmental managers, policy makers and remote sensing experts to interact and share ideas needs to be identified to support long-term coordinated actions.
Environmental science : Agree on biodiversity metrics to track from space
Skidmore, A.K. ; Pettorelli, Nathalie ; Coops, N.C. ; Geller, G.N. ; Hansen, Matthew ; Lucas, Richard ; Mücher, Sander ; O'Connor, Brian ; Paganini, Marc ; Pereira, Henrique Miguel ; Schaepman, M.E. ; Turner, Woody ; Wang, Tiejun ; Wegmann, Martin - \ 2015
Nature 523 (2015)7561. - ISSN 0028-0836 - p. 403 - 405.
High Spectral Resolution Image Processing for Mapping, Quantifying and Detecting Biodiversity II
Skidmore, A.K. ; Mücher, C.A. ; Wegmann, M. ; Pettorelli, N. ; Wang, T. - \ 2015
Free and open-access satellite data are key to biodiversity conservation
Turner, W. ; Rondinini, C. ; Pettorelli, N. ; Mora, B. ; Leidner, A.K. ; Szantoi, Z. ; Buchanan, G. ; Dech, S. ; Dwyer, J. ; Herold, M. ; Koh, L.P. ; Leimgruber, P. ; Taubenboeck, H. ; Wegmann, M. ; Wikelski, M. ; Woodcock, C. - \ 2015
Biological Conservation 182 (2015). - ISSN 0006-3207 - p. 173 - 176.
landsat imagery - cover change - science - opportunities - challenges - support - system
Satellite remote sensing is an important tool for monitoring the status of biodiversity and associated environmental parameters, including certain elements of habitats. However, satellite data are currently underused within the biodiversity research and conservation communities. Three factors have significant impact on the utility of remote sensing data for tracking and understanding biodiversity change. They are its continuity, affordability, and access. Data continuity relates to the maintenance of long-term satellite data products. Such products promote knowledge of how biodiversity has changed over time and why. Data affordability arises from the cost of the imagery. New data policies promoting free and open access to government satellite imagery are expanding the use of certain imagery but the number of free and open data sets remains too limited. Data access addresses the ability of conservation biologists and biodiversity researchers to discover, retrieve, manipulate, and extract value from satellite imagery as well as link it with other types of information. Tools are rapidly improving access. Still, more cross-community interactions are necessary to strengthen ties between the biodiversity and remote sensing communities.
Correspondence - Satellites: Make data freely accessible
Turner, W. ; Buchanan, G. ; Rondini, C. ; Dwyer, J. ; Herold, M. ; Koh, L.P. ; Leidner, A. ; Leimgruber, P. ; Mora, B. ; Pettorelli, N. ; Szantoi, Z. ; Taubenboeck, H. ; Wegmann, M. ; Wikelski, M. - \ 2013
Nature 498 (2013)7452. - ISSN 0028-0836 - p. 37 - 37.
Essential Biodiversity Variables
Pereira, H.M. ; Ferrier, S. ; Walters, M. ; Geller, G. ; Jongman, R.H.G. ; Scholes, R.J. ; Bruford, M.W. ; Brummitt, N. ; Butchart, S.H.M. ; Cardoso, A.C. ; Coops, N.C. ; Dulloo, E. ; Faith, D.P. ; Freyhof, J. ; Gregory, R.D. ; Heip, C. ; Höft, R. ; Hurtt, G. ; Jetz, W. ; Karp, D. ; McGeoch, M.A. ; Obura, D. ; Onoda, Y. ; Pettorelli, N. ; Reyers, B. ; Sayre, R. ; Scharlemann, J.P.W. ; Stuart, S.N. ; Turak, E. ; Walpole, M. ; Wegmann, M. - \ 2013
Science 339 (2013)6117. - ISSN 0036-8075 - p. 277 - 278.
global biodiversity - indicators - system - map
Reducing the rate of biodiversity loss and averting dangerous biodiversity change are international goals, reasserted by the Aichi Targets for 2020 by Parties to the United Nations (UN) Convention on Biological Diversity (CBD) after failure to meet the 2010 target (1, 2). However, there is no global, harmonized observation system for delivering regular, timely data on biodiversity change (3). With the first plenary meeting of the Intergovernmental Science-Policy Platform on Biodiversity and Ecosystem Services (IPBES) soon under way, partners from the Group on Earth Observations Biodiversity Observation Network (GEO BON) (4) are developing—and seeking consensus around—Essential Biodiversity Variables (EBVs) that could form the basis of monitoring programs worldwide.
Assessing effects of temporal compositing and varying observation periods for large-area land-cover mapping in semi-arid ecosystems: Implications for global monitoring
Huttich, C. ; Herold, M. ; Wegmann, M. ; Cord, A. ; Strobach, B. ; Schmullius, C. ; Dech, S. - \ 2011
Remote Sensing of Environment 115 (2011)10. - ISSN 0034-4257 - p. 2445 - 2459.
time-series - african savannas - avhrr data - data sets - vegetation dynamics - igbp discover - random forest - classification - kalahari - tree
Land-cover is an important parameter in analyzing the state and dynamics of natural and anthropogenic terrestrial ecosystems. Land-cover classes related to semi-arid savannas currently exhibit among the greatest uncertainties in available global land cover datasets. This study focuses on the Kalahari in northeastern Namibia and compares the effects of different composite lengths and observation periods with class-wise mapping accuracies derived from multi-temporal MODIS time series classifications to better understand and overcome quality gaps in mapping semi-arid land-cover types. We further assess the effects of precipitation patterns on mapping accuracy using Tropical Rainfall Measuring Mission (TRMM) observation data. Botanical field samples, translated into the UN Land Cover Classification System (LCCS), were used for training and validation. Different sets of composites (16-day to three-monthly) were generated from MODIS (MOD13Q1) data covering the sample period from 2004 to 2007. Land-cover classifications were performed cumulatively based on annual and inter-annual feature sets with the use of random forests. Woody vegetation proved to be more stable in terms of omission and commission errors compared to herbaceous vegetation types. Generally, mapping accuracy increases with increasing length of the observation period. Analyses of variance (ANOVA) verified that inter-annual classifications significantly improved class-wise mapping accuracies, and confirmed that monthly composites achieved the best accuracy scores for both annual and inter-annual classifications. Correlation analyses using piecewise linear models affirmed positive correlations between cumulative mapping accuracy and rainfall and indicated an influence of seasonality and environmental cues on the mapping accuracies. The consideration of the inter-seasonal variability of vegetation activity and phenology cycling in the classification process further increases the overall classification performance of savanna classes in large-area land-cover datasets. Implications for global monitoring frameworks are discussed based on a conceptual model of the relationship between observation period and accuracy
Effect of natural stimulants with and without GR24 on broomrape germination
Dhanapal, G.N. ; Struik, P.C. ; Borg, S.J. ter - \ 1998
In: Current problems of Orobanche researches - p. 51 - 57.
Effect of natural stimulants with and without GR24 on broomrape germination
Dhanapal, G.N. ; Struik, P.C. ; Borg, S.J. ter - \ 1998
In: Abstracts of the 4th international workshop on Orobanche research, Albena, Bulgaria, 1998, 'Current problems of Orobanche Researches', K. Wegmann, L. Musselman & D. Joel (Eds.), Institute for wheat and sunflower 'Dobroudja', Bulgaria, 1998 - p. 12 - 12.
Broomrapes of tobacco in Bulgaria
Dhanapal, G.N. ; Struik, P.C. - \ 1998
In: Abstracts of the 4th international workshop on Orobanche research, Albena, Bulgaria, 1998, 'Current problems of Orobanche Researches', K. Wegmann, L. Musselman & D. Joel (Eds.), Institute for wheat and sunflower 'Dobroudja', Bulgaria, 1998 - p. 21 - 21.
Soil moisture, root architecture and broomrape (Orobanche crenata) infestation in Faba bean (Vicia faba).
Borg, S.J. ter; Ast, A. van - \ 1991
In: Proc. Int. Workshop Orobanche research, Obermarchtal, FRG. 1989: Progress in Orobanche research, K. Wegmann, L.J. Musselman (eds.). Univ. Tubingen, FRG - p. 278 - 292.
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