Earth Imaging and Exploration from Space: Satellites – Sensors – Applications; Marinko Oluić

Prikaz knjige

Earth Imaging and Exploration from Space: Satellites – Sensors – Applications; Marinko Oluić

Prikaz knjige

Veränderung von Landnutzung und Vegetationsbedeckung in der östlichen Sahelzone von 1972 bis 2003: Veränderung von Landnutzung und Vegetationsbedeckung in der östlichen Sahelzone von 1972 bis 2003

Seit den siebziger Jahren des vergangenen Jahrhunderts hat sich im Gebiet südlich der Stadt Gadarif im Ostsudan, am Ostende der Sahelzone gelegen, nicht nur infolge des Klimawandels, sondern auch aufgrund extremer agrarischer Nutzung eine signifikante Veränderung der Vegetationsbedeckung ergeben. Stark reduzierte Bodenerträge führten in den neunziger Jahren zu Stilllegungen von Ackerland. Mittels multitemporaler Satellitenbilddaten konnte die neuerliche Entwicklung der natürlichen Vegetationsverjüngung auf den Brachen nachgewiesen werden. Weiterer Schutz dieser Gebiete kann künftig die vollständige Regeneration der früheren Maximalvegetation eines Savannenwaldes zwischen den Äckern ermöglichen. Die festgestellten Landnutzungsbefunde werden mit den klimatischen Veränderungen in der östlichen Sahelzone in Verbindung gebracht.The period since the 1970s has seen significant changes to the vegetation cover in the region south of the city of Gadarif in East Sudan, at the eastern end of the Sahel, due to both the current climate change and extreme agricultural use. Seriously degraded harvests led to the abandoning of agricultural land in the 1990s. By means of multi-temporal satellite imagery, it has been possible to demonstrate the development of vegetation renewal on such land. Further protection of the areas could permit complete future regeneration of the previous maximum natural vegetation of a savannah between the agricultural fields. The ascertained land use changes are linked to the climatic changes in the Eastern Sahel

Application of spaceborne synthetic aperture radar data for extraction of soil moisture and its use in hydrological modelling at Gottleuba Catchment, Saxony, Germany

Hydrological modelling is a powerful tool for hydrologists and engineers involved in the planning and management of water resources. With the recent advent of computational power and the growing availability of spatial data, remote sensing and geographical information systems technologies can augment to a great extent the conventional methods used in rainfall run-off studies. That means it is possible to accurately describe the characteristics of watershed in particularly when determining the run-off response to rainfall inputs. The main objective of this study is to apply the potential application of spaceborne synthetic aperture radar (SAR) data (i.e. TerraSAR-X and Advanced Land Observing Satellite/Phased Array type L-band Synthetic Aperture Radar (ALOS PALSAR) for soil moisture retrieval) and to improve the spatial input parameters required for hydrological modelling. For the spatial database creation, a high-resolution 2-m aerial laser scanning digital terrain model, soil map, and land use map were used. Rainfall records were transformed into a run-off through hydrological parameterisation of the watershed using Hydrologic Engineering Center's Hydrologic Modelling System (HEC-HMS) software for rainfall run-off simulation. The Soil Conservation Services Curve Number and soil moisture accounting loss methods were selected to calculate the infiltration losses. In this research, soil moisture was derived from two different types of spaceborne SAR data: TerraSAR-X and ALOS PALSAR (L-band). The developed integrated hydrological model was applied to a flood prone area: Gottleuba Catchment in Pirna (Saxony, Germany). For model validation, 10 years historical precipitation data were used. The validated model was further optimised using the extracted soil moisture from SAR data. The simulation results showed a reasonable match between the simulated and the observed hydrographs. Hence, this paper confirms that TerraSAR-X and ALOS PALSAR (L-band) have a high potential for soil moisture mapping as a useful source of information and technique in hydrological modelling

Landslide hazard and risk analyses at a landslide prone catchment area using statistical based geospatial model.

This paper presents the application of remote sensing techniques, digital image analysis and Geographic Information System tools to delineate the degree of landslide hazard and risk areas in the Balik Pulau area in Penang Island, Malaysia. Its causes were analysed through various thematic attribute data layers for the study area. Firstly, landslide locations were identified in the study area from the interpretation of aerial photographs, satellite imageries, field surveys, reports and previous landslide inventories. Topographic, geologic, soil and satellite images were collected and processed using Geographic Information System and image processing tools. There are 12 landslide-inducing parameters considered for the landslide hazard analyses. These parameters are: topographic slope, topographic aspect, plan curvature, distance to drainage and distance to roads, all derived from the topographic database; geology and distance to faults, derived from the geological database; landuse/landcover, derived from Landsat satellite images; soil, derived from the soil database; precipitation amount, derived from the rainfall database; and the vegetation index value, derived from SPOT satellite images. In addition, hazard analyses were performed using landslide-occurrence factors with the aid of a statistically based frequency ratio model. Further, landslide risk analysis was carried out using hazard map and socio-economic factors using a geospatial model. This landslide risk map could be used to estimate the risk to population, property and existing infrastructure like transportation networks. Finally, to check the accuracy of the success-rate prediction, the hazard map was validated using the area under curve method. The prediction accuracy of the hazard map was 89%. Based on these results the authors conclude that frequency ratio models can be used to mitigate hazards related to landslides and can aid in land-use planning

Editorial : Advances in Mars Research and Exploration

Peer reviewedPublisher PD

Utilization of optical remote sensing data and geographic information system tools for regional landslide hazard analysis by using binomial logistic regression model

This paper deals with landslide hazard analysis using Geographic Information System (GIS) and remote sensing data for Cameron Highland, Malaysia. Landslide locations were identified in the study area from interpretation of aerial photographs and field surveys. Topographical/geological data and satellite images were collected and processed using GIS and image processing tools. There are ten landslide inducing parameters which are considered for the landslide hazards. These parameters are topographic slope, aspect, curvature and distance from drainage, all derived from the topographic database; geology and distance from lineament, derived from the geologic database; landuse from Landsat satellite images; soil from the soil database; precipitation amount, derived from the rainfall database; and the vegetation index value from SPOT satellite images. Landslide hazard was analyzed using landslide-occurrence factors employing the logistic regression model. The results of the analysis were verified using the landslide location data and compared with logistic regression model. The accuracy of hazard map observed was 85.73%. The qualitative landslide hazard analysis was carried out using the logistic regression model by doing map overlay analysis in GIS environment. This information could be used to estimate the risk to population, property and existing infrastructure like transportation network

Identification of potentially dangerous glacial lakes in the northern Tien Shan

Like in many other parts of the world, the glaciers in northern Tien Shan are receding, and the permafrost is thawing. Concomitantly, glacial lakes are developing. Historically, outbursts of these glacial lakes have resulted in severe hazards for infrastructures and livelihood. Multi-temporal space imageries are an ideal means to study and monitor glaciers and glacial lakes over large areas. Geomorphometric analysis and modelling allows to estimate the potential danger for glacial lake outburst floods (GLOFs). This paper presents a comprehensive approach by coupling of remote sensing, geomorphometric analyses aided with GIS modelling for the identification of potentially dangerous glacial lakes. We suggest a classification scheme based on an additive ratio scale in order to prioritise sites for detailed investigations. The identification and monitoring of glacial lakes was carried out semi-automatically using band ratioing and the normalised difference water index (NDWI) based on multi-temporal space imagery from the years 1971 to 2008 using Corona, ASTER and Landsat data. The results were manually edited when required. The probability of the growth of a glacial lake was estimated by analysing glacier changes, glacier motion and slope analysis. A permafrost model was developed based on geomorphometric parameters, solar radiation and regionalised temperature conditions which permitted to assess the influence of potential permafrost thawing. Finally, a GIS-based model was applied to simulate the possibly affected area of lake outbursts. The findings of this study indicate an increasing number and area of glacial lakes in the northern Tien Shan region. We identified several lakes with a medium to high potential for an outburst after a classification according to their outburst probability and their downstream impact. These lakes should be investigated more in detai

Heterogeneity in topographic control on velocities of Western Himalayan glaciers

Peer reviewedPublisher PD

Die SLUB im Dienst der Vermittlung raumbezogener graphischer Information

Unter dem Titel „Dresden auf Karten und Ansichten“ wurde anlässlich des 800-jährigen Jubiläums der sächsischen Landeshauptstadt eine Internetpräsentation ausgewählter Landkarten und Veduten von der Sächsischen Landesbibliothek – Staats- und Universitätsbibliothek Dresden (SLUB) realisiert. Analog-Digital-Wandlung der Originale, Aufbau der digitalen Sammlung sowie der Nutzungsvorgang mit all seinen Möglichkeiten werden im Detail beschrieben. Beispiele von Landschafts- und Stadtentwicklung anhand von historischen Landkarten illustrieren das Potential dieses Internettools. Abschließend wird noch auf das von der Deutschen Fotothek und der Kartensammlung der SLUB betreute Informationsportal der sächsischen Bibliotheken und Archive „Kartenforum Sachsen“ hingewiesen. In letzteres ist auch die Seite „Dresden auf Karten und Ansichten“ integriertTo mark the 800-year anniversary of the Saxon capital Dresden, an Internet presentation entitled "Dresden auf Karten und Ansichten" ("Dresden on Maps and Pictures") has been realised, gathering selected maps and historical depictions from the collections of the Sächsische Landesbibliothek, Staatsund Universitätsbibliothek (Saxon State and University Library, SLUB). The analogue/ digital conversion of the originals, the structure of the digital collection, and the manifold possibilities for use are explained in detail. Examples of how landscape and urban development is reflected in historical maps illustrate the potential of this Internet tool. Furthermore, the information portal of the Saxon libraries and archives, which is presented as "Kartenforum Sachsen" ("Map Forum Saxony") and is maintained by the German Photothek and the SLUB map department, is described briefly. The site "Dresden auf Karten und Ansichten" is also integrated into this portal