Land Cover Changes In Wetland Ecosystem – Case Study Biebrza Valley, Poland

The changes in the hydrological conditions and discontinuance of grass harvesting influenced changes in land cover. The main trend of changes concern increase of shrub land in place of wetland habitats. The aim of this project was to distinct at Biebrza Wetlands area changes in shrub extension in 2001-2010. The study has been performed in optical and microwave images. The following satellite data have been chosen: Landsat.TM, Landsat.ETM+, Terra.ASTER, ERS2.SAR, ENVISAT.ASAR and ALOS.PALSAR. Optical images from 2001, 2006 and 2010 respectively have been used for land cover classifications. Microwave images have been applied as auxiliary data for classification testing and for examining the changes in backscattering for 2001 and 2008 due to changes in shrub areas. As the results the maps of land cover classifications and biomass changes using NDVI were created. The results give possibilities to improve effective shrub monitoring using additional satellite data which characterize hydrological conditions. The procedure is difficult due to two processes that occurred during considered time 1.Increase of shrub encroachment from 2000 to 2008 and 2.Diminish the shrub area due to mowing the wetlands by Biebrza National Park Biebrza Wetlands belong to RAMSAR Convention and NATURA 2000. Observation by satellite give the possibility for monitoring and proper management of wetland area and support planning for mowing program which is led in Biebrza National Park.