IWRA Proceedings

AbstractThe Mekong Delta in Vietnam offers natural resources for several million inhabitants. However, a strong population increase, changing climatic conditions and regulatory measures at the upper reaches of the Mekong lead to severe changes in the Delta. Extreme flood events occur more frequently, drinking water availability is increasingly limited, soils show signs of salinization or acidification, species and complete habitats diminish. Integrated resource management is required to face these problems. With that detailed knowledge and hydrologic,-, hydraulic-, ecologic-, and sociologic factors must be available. Furthermore, the cooperation of national institutes as well as national, regional and local authorities needs to be strengthened. It is the goal of WISDOM to design and implement an Information System for the Mekong Delta, containing information from the fields of hydrology, sociology, information technology, and earth observation. The integration of such data will enable the end-user of the system to perform analyses on very specific questions; and thus will supply the end-user with a tool supporting regional planning activities. The bilateral German-Vietnamese project is tailored to facilitate a multidisciplinary approach linking both, earth sciences with social sciences and vice versa. Therefore the project is structured in goal-oriented work packages each of them executed by scientific experts at institutions from both sides, Germany and Vietnam. The scientific work packages include: 1. Knowledge Management, 2. Information System Architecture Design, 3. Water esources, River System and Water Related Hazards, 4. Water Knowledge and Livelihoods, 5. Data Integration and Remotely Sensed Products, 6. Capacity Building. The German Aerospace Centre is coordinating the research initiative on German side. This paper presents the first results of the WISDOM project from the field of remote sensing, data management, and information system design. In the field of remote sensing the derivation of flood information is one crucial activity for the analysis of the Mekong habitats and livelihoods. Water masks are frequently being derived for the projects three major study areas within the Mekong Delta: Can Tho province, Tam Nong district and Tra Cu district. Using TerraSAR-X data at 2.5m resolution over Cao Lanh Region in Tam Nong district from both, the rain and dry season, watermasks were derived representing the distribution of surface water. Products were derived automatically following a threshold-based image classification approach. Furthermore change detection has been performed giving quantitative information about change intensity and with that flood severity. The resulting datasets, along with digital elevation models, and hydro-meteorological data will be used as input for hydraulic model development and adjustment for flood prediction and forecast. The complete automatic process chain from TerraSAR-X product generation to hydrologic modelling and flood forecasting will be one key element of the information system. Furthermore, landcover information for regions of interest within the Delta has been derived from Landsat and Palsar satellite imagery. Pixel based and object-oriented approaches were therefore combined to ha hybrid classification approach. Up to date landcover maps are currently non-existent in the Delta. However, information on landuse, crop types, irrigation patterns and settlement distribution are crucial for the assessment of a region’s water consumption and demand. The Information System itself is designed based on a standard oriented modular software and hardware architecture comprising a data entry portal, automatic data ingestion, standardized spatial data infrastructures, a processing environment, and visualization-, query-, and analysis module. Key aspects are the derivation and integration of geodata derived as products from e.g. remotely sensed products further dealing as input to hydrologic modelling. The first demonstration unit of this information system will be presented in detail. All results will be discussed within the context of further expected results and the user requirements of the Vietnamese partners.