Das Projekt "Watershed sediment yield modelling for data scarce areas; a case study, Awash River Basin, Ethiopia" wird vom Umweltbundesamt gefördert und von Universität Stuttgart, Institut für Wasserbau durchgeführt. The main goal of the research was to device an alternative solution for watershed sediment yield modelling for data scarce areas where the existing physically based models can not be applicable. Awash River Basin in Ethiopia was selected as case study area. GIS data on soil, land use, precipitation, temperature, stream flow and suspended sediment yield was collected from the Federal Ministry of Water Resources of Ethiopia (FMWRE) and from the National Metrology Service Agency (NMSA) offices. Soil data obtained from FMWRE and Food and Agriculture Organization (FAO) world soil 1974 database was used for derivation of the soil erodibility factor (ERFAC) estimation equation. The ratio of silt to sand and clay content was considered as the governing factor for soil erodibility in developing the ERFAC equation. The SWAT2005 model was selected for calibration and validation of stream flow and sediment yield. A sensitivity analysis was carried out to prioritize model calibration parameters. From the sensitivity analysis, curve number II (CN2), soilwater available to plants (SOL-AWC) and ground water base flow factor (ALPHA-BF) were selected as major stream flow calibration parameters. Similarly CN2, SURLAG (surface lag), slope and sediment routing factor (SPCON) were taken as the major sediment calibration parameters. Parameters related to the soil properties and river channel characteristics were given special attention during the model calibration. Eleven years (1990-2000) stream flow and sediment data were used for model calibration and six years data (2001-2006) were used for model validation. Calibration has been done at three gauging stations located in the Awash River basin. The statistical indicators, Coefficient of determination (R2), Nash-Sutclife efficiency (NSE), Root mean square error observations standard deviation (RSR were applied to evaluate the calibration and validation results. The values of these indicators were used to ratethe performance of the model. Watershed geomorphologic and topographic factors were extracted from the SWAT2005 watershed configuration, using a GIS tool and empirical equations. The relative importance of the factors was determined using Pearsons correlation coefficient based on the sediment yield output obtained from the SWAT2005 model calibration. The results show that, the sediment yield is highly correlated with stream flow, watershed area and watershed slope. Based on the identified parameters and the SWAT2005 model output, an alternative sediment yield estimation equation was derived and checked for its validity.
Das Projekt "Operating a Network of Integrated Observatory Systems In The Mediterranean Sea (ODYSSEA)" wird vom Umweltbundesamt gefördert und von Democritus University of Thrace durchgeführt. ODYSSEA will develop, operate and demonstrate an interoperable and cost-effective platform that fully integrates networks of observing and forecasting systems across the Mediterranean basin, addressing both the open sea and the coastal zone. The platform will collect its data from the many databases maintained by agencies, public authorities, and institutions of Mediterranean EU and non-EU countries, integrating existing earth observation facilities and networks in the Mediterranean Sea building on key initiatives such as Copernicus, GEOSS, GOOS, EMODNet, ESFRI, Lifewatch, Med-OBIS, GBIF, AquaMaps, Marine IBA e-atlas, MAPAMED and others with marine and maritime links. Through ODYSSEA's end-user centred approach, in which the various groups of end-users and stakeholders, within and external to the Consortium, will be involved from Day 1 of the project in the design, development and operation of the platform, including identification of gaps in data collection and accessibility. High priority gaps will be filled through multiple approaches that include developing a network of coastal observatories, deploying novel in-situ sensors at sea (a.o. microplastic sensors), oceanographic modelling and integrating existing mobile apps for citizen scientist networks. Applying advanced algorithms to organise, homogenise and fuse the large quantities of data in common standard type and format as well as other types of formats, the ODYSSEA platform will provide both primary data and on-demand derived data services, including forecasts, from ALL Mediterranean countries through a SINGLE PUBLIC PORTAL to various end-user groups and stakeholders. End-user requirements will drive the creation of secondary data sets which the platform will provide as new and packaged services matching the specialised information needs of users. ODYSSEA will improve accessibility to existing data as well as increase the temporal and geographic coverage of observational data in the Mediterranean.