Ioannis Manakos

Dr. Ioannis Manakos

Centre for Research and Technology Hellas, Information Technologies Institute, Hellas 6th km Harilaou-Thermi, 57001 Thessaloniki, Greece
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Research Focus & Metrics

Academic Career Length

14Years (2013-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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6 August 2018 in Methods in Ecology and Evolution
Verified
Journal Article
Open access
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DPDamiano Pasetto
Damiano Pasetto
Salvador Arenas-CastroSalvador Arenas-Castro
Salvador Arenas-Castro
Javier BustamanteJavier Bustamante
Javier Bustamante
RCRenato Casagrandi
Renato Casagrandi
Chrysoulakis NektariosChrysoulakis Nektarios
Chrysoulakis Nektarios
GZGuy Ziv
Guy Ziv
Spatiotemporal ecological modelling of terrestrial ecosystems relies on climatological and biophysical Earth observations. Due to their increasing availability, global coverage, frequent acquisition and high spatial resolution, satellite remote sensing (SRS) products are frequently integrated to in situ data in the development of ecosystem models (EMs) quantifying the interaction among the vegetation component and the hydrological, energy and nutrient cycles. This review highlights the main advances achieved in the last decade in combining SRS data with EMs, with particular attention to the challenges modellers face for applications at local scales (e.g. small watersheds). We critically review the literature on progress made towards integration of SRS data into terrestrial EMs: (1) as input to define model drivers; (2) as reference to validate model results; and (3) as a tool to sequentially update the state variables, and to quantify and reduce model uncertainty. The number of applications provided in the literature shows that EMs may profit greatly from the inclusion of spatial parameters and forcings provided by vegetation and climatic‐related SRS products. Limiting factors for the application of such models to local scales are: (1) mismatch between the resolution of SRS products and model grid; (2) unavailability of specific products in free and public online repositories; (3) temporal gaps in SRS data; and (4) quantification of model and measurement uncertainties. This review provides examples of possible solutions adopted in recent literature, with particular reference to the spatiotemporal scales of analysis and data accuracy. We propose that analysis methods such as stochastic downscaling techniques and multi‐sensor/multi‐platform fusion approaches are necessary to improve the quality of SRS data for local applications. Moreover, we suggest coupling models with data assimilation techniques to improve their forecast abilities. This review encourages the use of SRS data in EMs for local applications, and underlines the necessity for a closer collaboration among EM developers and remote sensing scientists. With more upcoming satellite missions, especially the Sentinel platforms, concerted efforts to further integrate SRS into modelling are in great demand and these types of applications will certainly proliferate.

8 June 2018 in Remote Sensing
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Journal Article
Open access
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GKGeorgios A. Kordelas
Georgios A. Kordelas
Ioannis ManakosIoannis Manakos
Ioannis Manakos
DADavid Aragones
David Aragones
Ricardo Díaz-DelgadoRicardo Díaz-Delgado
Ricardo Díaz-Delgado
Javier BustamanteJavier Bustamante
Javier Bustamante
Satellite data offer the opportunity for monitoring the temporal flooding dynamics of seasonal wetlands, a parameter that is essential for the ecosystem services these areas provide. This study introduces an unsupervised approach to estimate the extent of flooded areas in a satellite image relying on the physics of light interaction with water, vegetation and their combination. The approach detects automatically thresholds on the Short-Wave Infrared (SWIR) band and on a Modified-Normalized Difference Vegetation Index (MNDVI), derived from radiometrically-corrected Sentinel-2 data. Then, it combines them in a meaningful way based on a knowledge base coming out of an iterative trial and error process. Classes of interest concern water and non-water areas. The water class is comprised of the open-water and water-vegetation subclasses. In parallel, a supervised approach is implemented mainly for performance comparison reasons. The latter approach performs a random forest classification on a set of bands and indices extracted from Sentinel-2 data. The approaches are able to discriminate the water class in different types of wetlands (marshland, rice-paddies and temporary ponds) existing in the Doñana Biosphere Reserve study area, located in southwest Spain. Both unsupervised and supervised approaches are examined against validation data derived from Landsat satellite inundation time series maps, generated by the local administration and offered as an online service since 1983. Accuracy assessment metrics show that both approaches have similarly high classification performance (e.g., the combined kappa coefficient of the unsupervised and the supervised approach is 0.8827 and 0.9477, and the combined overall accuracy is 97.71% and 98.95, respectively). The unsupervised approach can be used by non-trained personnel with a potential for transferability to sites of, at least, similar characteristics.

1 May 2015 in International Journal of Applied Earth Observation and Geoinformation
Verified
Journal Article
Open access
RLRichard Lucas
Richard Lucas
PBPalma Blonda
Palma Blonda
Pete BuntingPete Bunting
Pete Bunting
GJGwawr Jones
Gwawr Jones
JIJordi Inglada
Jordi Inglada
PMPaola Mairota
Paola Mairota

1 January 2014 in Ecological Indicators
Verified
Journal Article
Closed access
VKVasiliki Kosmidou
Vasiliki Kosmidou
ZPZisis Petrou
Zisis Petrou
RBRobert G.H. Bunce
Robert G.H. Bunce
CMCaspar A. Mücher
Caspar A. Mücher
RJRobert H.G. Jongman
Robert H.G. Jongman
MPMaria Petrou
Maria Petrou

1 May 2015 in International Journal of Applied Earth Observation and Geoinformation
Verified
Journal Article
Closed access
HNHarini Nagendra
Harini Nagendra
PMPaola Mairota
Paola Mairota
CMCarmela Marangi
Carmela Marangi
RLRichard Lucas
Richard Lucas
PDPanayotis Dimopoulos
Panayotis Dimopoulos
PBPalma Blonda
Palma Blonda