Online data services at the Belgian Marine Datacentre

Over the past few years, the Management Unit of the North Sea Mathematical Models (MUMM) has built up a centre of human and technical expertise oriented towards the management and the analysis of marine environmental data. The Belgian Marine Data Centre (BMDC) serves as national repository and processing centre for marine and environmental data and ensures a continuous and scientifically sound data flow between data producers and end-users of marine and environmental data collected in the frame of national and international research and monitoring programmes. The data cover most domains of oceanology as there are: physico-chemical, optical parameters, biodiversity, hydrodynamics, sedimentology, geography and human interest. Most of the datasets relate to the Belgian Continental Shelf, the Scheldt estuary and its surrounding areas.To promote the use of a high variety of data sets, different tools are constantly being developed and are presented on our website (www.mumm.ac.be/datacentre). An interface to the integrated database on the quality of the marine environment was developed. This database mainly contains the results of measurements and observations in situ and laboratory analyses of air, water, sediment and biota samples. Besides an extensive inventory of the database and an advanced request form with several selection criteria, some more straightforward queries and geographical selection tools are being developed for a faster and easier access to a specific dataset. Data can freely be downloaded. Once the data are obtained, a spatial analysis tool is freely and online available for the visualization on an interactive map. A lot of documentation accompanying the data is online available. The strongest feature of this system is the common underlying structure for different kinds and sources of data. This opens the possibility to compare biodiversity data, physico-chemical data, sedimentological data and historical data.Another database at MUMM, the real-time data acquisition system ‘ODAS’ stores the physical and chemical parameters measured onboard of the research vessel RV Belgica since 1984. The along -track data are published online shortly after the end of the measurement campaign together with all other information like the campaign reports, cruise tracks, … This is a valuable source of basic information for the scientists

Online data services at the Belgian Marine Datacentre

Over the past few years, the Management Unit of the North Sea Mathematical Models (MUMM) has built up a centre of human and technical expertise oriented towards the management and the analysis of marine environmental data. The Belgian Marine Data Centre (BMDC) serves as national repository and processing centre for marine and environmental data and ensures a continuous and scientifically sound data flow between data producers and end-users of marine and environmental data collected in the frame of national and international research and monitoring programmes. The data cover most domains of oceanology as there are: physico-chemical, optical parameters, biodiversity, hydrodynamics, sedimentology, geography and human interest. Most of the datasets relate to the Belgian Continental Shelf, the Scheldt estuary and its surrounding areas.To promote the use of a high variety of data sets, different tools are constantly being developed and are presented on our website (www.mumm.ac.be/datacentre). An interface to the integrated database on the quality of the marine environment was developed. This database mainly contains the results of measurements and observations in situ and laboratory analyses of air, water, sediment and biota samples. Besides an extensive inventory of the database and an advanced request form with several selection criteria, some more straightforward queries and geographical selection tools are being developed for a faster and easier access to a specific dataset. Data can freely be downloaded. Once the data are obtained, a spatial analysis tool is freely and online available for the visualization on an interactive map. A lot of documentation accompanying the data is online available. The strongest feature of this system is the common underlying structure for different kinds and sources of data. This opens the possibility to compare biodiversity data, physico-chemical data, sedimentological data and historical data.Another database at MUMM, the real-time data acquisition system ‘ODAS’ stores the physical and chemical parameters measured onboard of the research vessel RV Belgica since 1984. The along -track data are published online shortly after the end of the measurement campaign together with all other information like the campaign reports, cruise tracks, … This is a valuable source of basic information for the scientists

Revealing species communities in a spatial and temporal overlap

Storing physical and chemical values, optical spectra and sediment granulometry is already a cumbersome task; dealing with biological data even falls into a different category. Biologists tend to focus their attention to species of their interest while other specimens in the same sample are often underestimated. Meanwhile taxonomists are continuously revising the taxonomy resulting in a complete new set of relations between these taxa. Keeping track with both and meanwhile having a dataset up to date seems endless. At the Belgian Marine Data Centre we tried to think outside the box and came up with a solution to content both biologists and data managers. The last thing we aimed at is to create another web index to refer species, therefore we hooked up with the existing web based referencing systems. The need to get data about different food webs in a spatial and temporal overlap is answered by our hierarchical storage of taxa which allows selecting a predator at species level and at the same time selecting different prey species at lower taxonomic levels. As these species, and also the scientists, usually are not confined into ‘latitude longitude squares’ we elaborated the spatial selection tool which defines user specific polygons to base the selection of data upon. We will briefly present the structure of our relational database but specific attention will go out to the taxonomic and spatial parts. Incentives and discomforts to organize the data in this way, and our current web interface, will be demonstrated

Optical remote sensing in support of eutrophication monitoring in the southern North Sea

Spring mean and maximum chlorophyll a (chla) concentrations are main factors to determine the eutrophication status of the Belgian waters as agreed within OSPAR in 2002. Other important assessment parameters to measure the degree of nutrient enrichment - the amounts of inorganic phosphate and nitrogen in winter - appeared to be above thresholds for most measurements performed in the period 1974-2002. As the standard in situ monitoring programme does not give a clear picture of the temporal and spatial distribution of chl a, it is logical to complement these measurements with optical remote sensing. However, chlorophyll concentrations derived from sensors such as SeaWiFS are unreliable in the Case 2 waters of this region because of high particulate and dissolved yellow substance absorption. Another important limitation of ocean colour sensors is the amount of useful images due to cloud cover. The combination of data from different ocean colour sensors in order to enable a better temporal coverage might be hampered by the different chlorophyll retrieval algorithms used. This study compares different global chl a algorithms (MODIS, SeaWiFS, MERIS) as well as a turbid water algorithm for the Southern North Sea. This is done by running the different algorithms on in situ reflectance spectra collected at 107 stations in the period 2001-2002 over the Southern North Sea and comparing them with in situ chl a concentrations, as well as by running the algorithms on a MERIS image of the 29th of July 2002. Based on this validation the accuracy of these products and their suitability for eutrophication monitoring in the Southern North Sea are assessed