Untersuchung der Tsunami-Vulnerabilität von Küstenökosystemen an der Andamanenküste Thailands - Potential & Grenzen eines GIS- und fernerkundungsgestützten Ansatzes auf lokaler Skala

The thesis deals with the assessment of tsunami vulnerability and resilience of coastal ecosystems at the Andaman coast of Thailand by applying a remote sensing based approach. Object-oriented image analysis, change detection techniques and field investigations are used to a) retrospectively investigate the spatial patterns of tsunami vulnerability and b) to evaluate the potential and limitations of using high-resolution imagery (here IKONOS data) in the field of tsunami vulnerability and risk analysis. The results show that vulnerability varied strongly in space and in ecosystem type: although being little exposed to tsunamis, mangrove forests locally turned out to be a vulnerable ecosystem. Furthermore, the study revealed that remote sensing techniques can be an effective tool for the assessment of tsunami vulnerability. Furthermore, a valuable (geo)-data basis was created serving as a flexible starting point for further investigations on ecological and socio-ecological vulnerability.Die Arbeit widmet sich der Thematik der Abschätzung der Tsunami-Vulnerabilität und Resilienz von Küstenökosystemen an der Andamanküste Thailands unter Nutzung eines fernerkundungsbasierten Ansatzes. Feldmessungen, objektorientierte Bildanalyse sowie Verfahren der Veränderungsdetektion werden dabei zur retrospektiven Abschätzung der Tsunami-Vulnerabilität eingesetzt. Dabei werden auch die Potentiale und Grenzen von Fernerkundungsanwendungen im Kontext der Vulnerabilitäts- und Risikoanalyse beurteilt. Die Ergebnisse zeigen, dass die Vulnerabilität räumlich und je nach Ökosystemtyp stark variiert: Mangrovenwälder haben sich beispielsweise als gering exponiertes, lokal jedoch als vulnerables Ökosystem herausgestellt. Die Studie verdeutlicht weiterhin, dass Fernerkundung ein effektives Werkzeug für die Abschätzung der Tsunamivulnerabilität darstellt, wobei eine Geodatenbank generiert wurde, die sich als Anknüpfungspunkt für weitergehende Studien zur ökologischen und sozio-ökologischen Vulnerabilität eignet

Developing a method to map coconut agrosystems from high-resolution satellite images

https://icaci.org/files/documents/ICC_proceedings/ICC2015/papers/38/fullpaper/T38-504_1427765394.pdfInternational audienceOur study aims at developing a generalizable method to exploit high resolution satellite images(VHR) for mapping coconut-based agrosystems, differentiating them from oil palm agrosystems.We compared two methods of land use classification. The first one is similar to that described byTeina (2009), based on spectral analysis and watershed segmentation, which we simplified byusing the NDVI vegetation index. The second one is the semi-automatic classification based ontexture analysis (PAPRI method of Borne, 1990). These methods were tested in two differentenvironments: Vanua Lava (Vanuatu; heterogeneous landscape, very ancient plantations) andIvory Coast (Marc Delorme Research Station, monoculture, regular spacing, oil palm plantations);and their results were evaluated against manually digitized photo-interpretation maps.In both situations, the PAPRI method produced better results than that of Teina (global kappa of0.60 vs. 0.40). Spectral signatures do not allow a sufficiently accurate mapping of coconut and donot differentiate it from oil palm, despite their different NDVI signatures. The PAPRI methoddifferentiates productive coconut from mixed plantations and other vegetation, either high or low(70% accuracy). In both situations, Teina’s method allows counting 65% of the coconut treeswhen they are well spaced. To increase the method accuracy, we suggest (1) field surveys (forsmall scale studies) and/or finer image resolution, allowing a high precision in manual mappingwith a better discrimination between coconut and oil palm, thus limiting the proportion of mixedpixels. (2) A phenological monitoring could improve the distinction between coconut and oil palmagrosystems. (3) Hyper-spectral images should allow extracting more precisely the respectivesignatures of both species. Another possibility would be (4) an object-oriented analysis asproposed by the eCognition software. Finally, (5) coupling the Lidar system with watershedanalysis would allow a better characterization of coconut varietal types

Land use change detection of small scale sugarcane : a case study of Umbumbulu, South Africa

Thesis (M.Env.Dev.) - University of KwaZulu-Natal, Pietermaritzburg, 2009.The aim of this study was to detect spatio-temporal changes in sugarcane land use using satellite imagery for 1991–2006 in Umbumbulu, South Africa. This change detection study will enable quantification of change and the changes between different land use and land cover that has occurred over the study period 1991–2006. This work embarked on a change detection analysis using image-processing software namely ERDAS, IDRISI and ArcGIS to complete the study. Three Landsat TM images from 1991, 2001, and 2006 were used. The images were geometrically corrected to a common map projection, followed by image processing operations namely: radiometric correction, supervised image classification, accuracy assessment and post classification comparison change detection. Each image was separately classified into land cover categories of water, grassland, mix bush/shrub, forestry, sugarcane and built-up land using the supervised classification maximum likelihood algorithm in ERDAS. Final classification accuracy was determined to be ‘satisfactory’ or ‘good’ by means of employing standardized accuracy assessment measures, the error matrix. The post-classification comparison technique was applied to compare the classified images to assess for changes in sugarcane land use over time using IDRISI software. The classified images produced were exported into ArcMap GIS software for additional change analysis. The results are displayed as change maps. Change analysis has been executed based on digital interpretation of classification results

Urban morphology analysis by remote sensing and gis technique, case study: Georgetown, Penang

This paper was analysed the potential of applications of satellite remote sensing to urban planning research in urban morphology. Urban morphology is the study of the form of human settlements and the process of their formation and transformation. It is an approach in designing urban form that considers both physical and spatial components of the urban structure. The study conducted in Georgetown, Penang purposely main to identify the evolution of urban morphology and the land use expansion. In addition, Penang is well known for its heritage character, especially in the city of Georgetown with more than 200 years of urban history. Four series of temporal satellite SPOT 5 J on year 2004, 2007, 2009 and 2014 have been used in detecting an expansion of land use development aided by ERDAS IMAGINE 2014. Three types of land uses have been classified namely build-up areas, un-built and water bodies show a good accuracy with achieved above 85%. The result shows the built-up area significantly increased due to the rapid development in urban areas. Simultaneously, this study provides an understanding and strengthening a relation between urban planning and remote sensing applications in creating sustainable and resilience of the city and future societies as well

Evaluating the impact of road infrastructure on household income in Papua New Guinea:Spatial data compilation and analysis

As part of the ADB sub‐project ‘Developing Impact Evaluation Methodologies, Approaches, and Capacities in Selected Developing Member Countries’ two closely related research projects were carried out by VU to evaluate the impact of road infrastructure on household income in Papua New Guinea. One project focused on econometric analysis (contract no. 117629‐S85196), while the other developed the spatial database needed for this analysis (contract no. 117642‐S84962). The current report documents the data collection process and provides a concise description of the data that were collected for the project and the analyses that were performed to enrich the available data sources to create meaningful variables for the statistical analysis. It serves as a background document with the scientific paper‐that concisely describes the findings of the two joint research projects

Forest cover and its change in Unguja Island, Zanzibar

Tropical forests are sources of many ecosystem services, but these forests are vanishing rapidly. The situation is severe in Sub-Saharan Africa and especially in Tanzania. The causes of change are multidimensional and strongly interdependent, and only understanding them comprehensively helps to change the ongoing unsustainable trends of forest decline. Ongoing forest changes, their spatiality and connection to humans and environment can be studied with the methods of Land Change Science. The knowledge produced with these methods helps to make arguments about the actors, actions and causes that are behind the forest decline. In this study of Unguja Island in Zanzibar the focus is in the current forest cover and its changes between 1996 and 2009. The cover and changes are measured with often used remote sensing methods of automated land cover classification and post-classification comparison from medium resolution satellite images. Kernel Density Estimation is used to determine the clusters of change, sub-area –analysis provides information about the differences between regions, while distance and regression analyses connect changes to environmental factors. These analyses do not only explain the happened changes, but also allow building quantitative and spatial future scenarios. Similar study has not been made for Unguja and therefore it provides new information, which is beneficial for the whole society. The results show that 572 km2 of Unguja is still forested, but 0,82–1,19% of these forests are disappearing annually. Besides deforestation also vertical degradation and spatial changes are significant problems. Deforestation is most severe in the communal indigenous forests, but also agroforests are decreasing. Spatially deforestation concentrates to the areas close to the coastline, population and Zanzibar Town. Biophysical factors on the other hand do not seem to influence the ongoing deforestation process. If the current trend continues there should be approximately 485 km2 of forests remaining in 2025. Solutions to these deforestation problems should be looked from sustainable land use management, surveying and protection of the forests in risk areas and spatially targeted self-sustainable tree planting schemes.Siirretty Doriast

Detection, monitoring and management of small water bodies:: A case study of Shahjadpur Thana, Sirajgonj district, Bangladesh

Bangladesh is a low-lying flood prone deltaic plain. Excavations are needed to create raised land for safe flood-free homesteads and water bodies for irrigation, and these result in the creation of doba, pukur, dighi and jola. All of these types of small water bodies are almost equally distributed all over the country, except for the heel, which is a natural, saucer shaped depression. For every eight people there is approximately an acre of small water bodies, which range in size from 25-400 sq.m. (doba), 150-1000 sq.m. (pukur), >750 sq.m. (dighi), >2000 sq.m. (jola) and >1000 sq.m. (heel). These small water bodies are commonly used for drinking, bathing and washing, fisheries and aquaculture, duck raising, irrigation, cattle feeding and washing. Despite the importance of small water bodies to the local economy there is no up to date inventory. For this purpose, in my research I have employed integrated participatory remote sensing, GIS and socio-cultural approaches. Although these have not been used before in Bangladesh, 1 argue that they are ideal for effective resource management and sustainable development planning. This research investigated the historical development of the present spatial distribution and use patterns of SWB using Remote Sensing and GIS. This was at a regional scale in four mouzas of Shahjadpur Thana. The data sources were topographical maps, aerial photographs, satellite images, agricultural census data, in-depth questionnaire, focus group meetings and interviewing key informants. An integrated RS-GIS and social sciences methodology was employed to produce maps of change and overlays of the socio-cultural factors involved. Results show that the doba, pukur and dighi, when these are not obstructed by surrounding vegetation, can be detected easily in high resolution panchromatic CORONA satellite photography, IRS-ID Panchromatic image and aerial photography. Comparatively large pukurs, dighis and all jo las and heels are detected in all other optical sensors and the SIR-C radar imagery. Multi-temporal images are helpful for identifying the different types of small water bodies as well separating those from other seasonal large water bodies and flooded areas. It is hoped that the proposed computer assisted participatory management system, including some locally specific guidelines, may be applicable for the planning of other thanas (total 490) in Bangladesh. The proposed management system will facilitate the integration of local planning with the national level planning process, which has not been possible hitherto

Fragmented Landscapes: An Archaeology of Transformations in The Pra River Basin, Southern Ghana

This doctoral archaeological research examines the Pra River Basin in southern Ghana through lenses of landscape, temporality, and transformation. Drawing on the Annales school and the writings of Tim Ingold, this study moves away from binary constructions of natural and cultural landscape features toward a more integrated view of the landscape\u27s long human history. The primary temporal focus of this research is the past three millennia but evidence recovered of even more ancient eras is also examined. The artifacts and features documented while surveying this landscape allow us to glimpse pre-Atlantic (pre-1450 CE) settlement patterns, subsistence, and technology, as well as more recent and ongoing transformations of the landscape. Artifacts including ceramics, quartz flakes, stone beads, ground stone tools, and iron slag were found on hilltop sites throughout the surveyed areas. Most of these sites represent a pre-Atlantic pattern of settlement that continues, to a lesser extent, into the early Atlantic era (1450-1700 CE). Long grinding slicks, possibly related to Nyame Akuma production, are present on numerous rock outcrops in the region. Test excavation at an iron smelting site near Adiembra (AD31) yielded a temporally extensive range of dates. The bulk of the slag was deposited in the early second century CE, but deeper ceramic bearing contexts stretched back through the first millennium BCE. A single early seventh millennium BCE date associated with stone flakes underlay the site, representing the oldest date recovered from an archaeological context in the region. The archaeological evidence this study presents suggests the entire landscape has undergone continual alteration for numerous millennia, but much of the landscape\u27s current form represents Atlantic influences and more recent historical dynamics and transformations of the colonial and post-colonial periods. I examine this fragmented landscape using satellite remote sensing, archaeological pedestrian survey, diagnostic artifact analyses, and limited test excavations to identify and assess features and transformative processes