Applications

Inland water monitoring

Since December 2000 the European Union Water Framework Directive (WFD, 2000/60/EC) forms the legislative framework for the water management undertaken by the EU Member States. The directive requires the monitoring of biological, physico-chemical and hydromorphological parameters within river basins, lakes, transitional and coastal waters in order to achieve a good status of surface waters by 2015. The WFD has been implemented in 2003 by the Flemish government by means of the Decree Integrated Water Policy (DIWP). To meet the objectives of the WFD strict monitoring requirements are specified. Remote sensing can support the implementation of the WFD by providing synoptic coverage of river systems and lakes and by providing systematic observations to monitor and assess status and trends.

This is illustrated with several case studies: (1) quantification of water quality parameters (chlorophyll-a, suspended sediments) in recreational lakes (results in progress) and in the Scheldt river, (2) classification of salt marshes and mud flats along the Scheldt river using LIDAR and hyperspectral airborne data (Figure 1), (3) assessment of spatial and temporal variation of microphytobentos biomass at intertidal flats through combination of yearly hyperspectral campaigns and in-situ data (Figure 2).

Figure 1. Operational classification of salt marches and mudflats with hyperspectral airborne remote sensing (Source: VITO-INBO-Houthuys under the authority of Flanders Maritime Access Division)

Figure 2. Spatial and temporal variation of NDVI as indicator of chlorophyll. NDVI values higher than 0.5 indicate the presence of salt mashes. NDVI values between 0.2 and 0.5 indicate microphytobenthos (MPB) (low MPB concentration NDVI 0.2 -0.5 ; medium MPB concentration NDVI 0.25-0.3 and high MPB concentration NDVI 0.3 -0.5)(Source: VITO, under the authority of Flanders Maritime Access Division and The Netherlands Institute of Ecology NIOO)