Ioannis Tsolakidis - Academia.edu (original) (raw)
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Papers by Ioannis Tsolakidis
Environmental Processes, 2019
This paper investigates two mapping methods for Kerkini reservoir bottom, in order to study the m... more This paper investigates two mapping methods for Kerkini reservoir bottom, in order to study the morphology and the evolution of deposits at the reservoir. The methods are the hydrographic and the satellite bathymetry. The hydrographic method incorporates the geodetic satellite technology with sonar system for mapping the bottom relief, while the satellite bathymetry extracts the depths using the information from the spectral bands of a satellite image. The satellite Worldview-2 was used in this study. The milestones for the Kerkini reservoir were the years 1952 and 1982, where the construction of the west dike changed the hydrological regime. After these changes, bottom surveys of the reservoir were carried out in 1962 and 1984 and charts were produced. Based on these diagrams, deposition rates are calculated and volumes are compared over the years till the recent mapping in 2014. The digital bathymetry models, obtained from the implementation of hydrography and satellite bathymetry, are compared to each other. Furthermore, the development of new methods for the determination of volume and deposition rate can contribute to the optimal management of such water systems and the creation of a sustainability index for the reservoir.
Η διαχείριση των υδάτινων πόρων για σκοπούς άρδευσης και αντιπλημμυρικής προστασίας, κατείχε σημα... more Η διαχείριση των υδάτινων πόρων για σκοπούς άρδευσης και αντιπλημμυρικής προστασίας, κατείχε σημαντικό ρόλο στην ανάπτυξη παλαιότερων αλλά και σύγχρονων πολιτισμών. Η ολοένα και μεγαλύτερη αύξηση του πληθυσμού, ειδικότερα μετά τον δέκατο ένατο αιώνα, με την ταυτόχρονη βιομηχανική επανάσταση, οδήγησε στη απαίτηση για βέλτιστη και αποτελεσματικότερη διαχείριση των υδάτινων πόρων. Ο ρόλος των ταμιευτήρων στο πρόβλημα της διαχείρισης υπήρξε καθοριστικός, παρ’ όλες τις αρνητικές επιδράσεις που μπορεί να έχει στο φυσικό περιβάλλον. Σήμερα με την ανάπτυξη των υπολογιστικών τεχνικών, οργάνων και συστημάτων, ο σχεδιασμός ενός συστήματος ταμιευτήρα είναι ακόμη πιο βέλτιστος. Παράλληλα με τον σχεδιασμό και τη λειτουργία των ταμιευτήρων, σχεδιάζονται και διαδικασίες παρακολούθησης των συστημάτων αυτών, που αφορούν στην εκτίμηση της φυσικοχημικής κατάστασης των υδάτων, της διακύμανσης της στάθμης αλλά και της αποθηκευτικής ικανότητας του ταμιευτήρα. Το τελευταίο είναι ιδιαίτερα κρίσιμο, κατά την...
IOP Conference Series: Earth and Environmental Science
The use of open satellite data has become a valuable tool for monitoring the urban environment du... more The use of open satellite data has become a valuable tool for monitoring the urban environment due to high temporal, spectral and spatial resolution. Planners and stakeholders can rely on these data since they offer an alternative point of view of a very complex urban scenery. The processing of satellite images with the combined use of different types of data (statistical, in situ etc) can extract information for the present situation, in urban and suburban areas. This study use image data from the Sentinel satellite mission, in order to extract urban land cover characteristics in Thessaloniki city. The Sentinel mission started the image acquisition on 2014. The data set are freely available for downloading. The use of high resolution satellite images (e.g IKONOS) in urban studies, has been proved very useful all these years. On the other hand the use of a medium size spatial resolution satellite, as Sentinel-2, with 10m pixel size, is a very promising optical earth-observation satellite, which is tested in this study. Image processing techniques used to produce classified map of urban characteristics and land cover classes (built up areas, vegetation etc). The contribution of a radar image of Sentinel-1, in the classification process, is also tested. All the above processing is done with an automatic procedure, giving additional value to the proposed methodology. The final classified map will give planners a management tool for decision-making concerning the sustainable urban development and will be the basis for implementing hydrology studies, planning, land use change detection and other.
Environmental Processes, 2019
This paper investigates two mapping methods for Kerkini reservoir bottom, in order to study the m... more This paper investigates two mapping methods for Kerkini reservoir bottom, in order to study the morphology and the evolution of deposits at the reservoir. The methods are the hydrographic and the satellite bathymetry. The hydrographic method incorporates the geodetic satellite technology with sonar system for mapping the bottom relief, while the satellite bathymetry extracts the depths using the information from the spectral bands of a satellite image. The satellite Worldview-2 was used in this study. The milestones for the Kerkini reservoir were the years 1952 and 1982, where the construction of the west dike changed the hydrological regime. After these changes, bottom surveys of the reservoir were carried out in 1962 and 1984 and charts were produced. Based on these diagrams, deposition rates are calculated and volumes are compared over the years till the recent mapping in 2014. The digital bathymetry models, obtained from the implementation of hydrography and satellite bathymetry, are compared to each other. Furthermore, the development of new methods for the determination of volume and deposition rate can contribute to the optimal management of such water systems and the creation of a sustainability index for the reservoir.
Η διαχείριση των υδάτινων πόρων για σκοπούς άρδευσης και αντιπλημμυρικής προστασίας, κατείχε σημα... more Η διαχείριση των υδάτινων πόρων για σκοπούς άρδευσης και αντιπλημμυρικής προστασίας, κατείχε σημαντικό ρόλο στην ανάπτυξη παλαιότερων αλλά και σύγχρονων πολιτισμών. Η ολοένα και μεγαλύτερη αύξηση του πληθυσμού, ειδικότερα μετά τον δέκατο ένατο αιώνα, με την ταυτόχρονη βιομηχανική επανάσταση, οδήγησε στη απαίτηση για βέλτιστη και αποτελεσματικότερη διαχείριση των υδάτινων πόρων. Ο ρόλος των ταμιευτήρων στο πρόβλημα της διαχείρισης υπήρξε καθοριστικός, παρ’ όλες τις αρνητικές επιδράσεις που μπορεί να έχει στο φυσικό περιβάλλον. Σήμερα με την ανάπτυξη των υπολογιστικών τεχνικών, οργάνων και συστημάτων, ο σχεδιασμός ενός συστήματος ταμιευτήρα είναι ακόμη πιο βέλτιστος. Παράλληλα με τον σχεδιασμό και τη λειτουργία των ταμιευτήρων, σχεδιάζονται και διαδικασίες παρακολούθησης των συστημάτων αυτών, που αφορούν στην εκτίμηση της φυσικοχημικής κατάστασης των υδάτων, της διακύμανσης της στάθμης αλλά και της αποθηκευτικής ικανότητας του ταμιευτήρα. Το τελευταίο είναι ιδιαίτερα κρίσιμο, κατά την...
IOP Conference Series: Earth and Environmental Science
The use of open satellite data has become a valuable tool for monitoring the urban environment du... more The use of open satellite data has become a valuable tool for monitoring the urban environment due to high temporal, spectral and spatial resolution. Planners and stakeholders can rely on these data since they offer an alternative point of view of a very complex urban scenery. The processing of satellite images with the combined use of different types of data (statistical, in situ etc) can extract information for the present situation, in urban and suburban areas. This study use image data from the Sentinel satellite mission, in order to extract urban land cover characteristics in Thessaloniki city. The Sentinel mission started the image acquisition on 2014. The data set are freely available for downloading. The use of high resolution satellite images (e.g IKONOS) in urban studies, has been proved very useful all these years. On the other hand the use of a medium size spatial resolution satellite, as Sentinel-2, with 10m pixel size, is a very promising optical earth-observation satellite, which is tested in this study. Image processing techniques used to produce classified map of urban characteristics and land cover classes (built up areas, vegetation etc). The contribution of a radar image of Sentinel-1, in the classification process, is also tested. All the above processing is done with an automatic procedure, giving additional value to the proposed methodology. The final classified map will give planners a management tool for decision-making concerning the sustainable urban development and will be the basis for implementing hydrology studies, planning, land use change detection and other.