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Floodplain forest response to changed soil moisture regime and nutrient availability due to river regulation was studied using remote sensing (ETM) data. Images of May and October 2001 were used to prepare NDVI, SAVI, 5/4-ratio images and ETM band 7. Comparisons of the LAI, NDVI, 5/4-ratios and ETM band 7 mean values were done to find out the differences between the flooded and non-flooded sites. Unsupervised clustering of images was done using single transformed channels, i.e. NDVI, SAVI, 5/4-ratio and ETM band 7 to find seasonal variations in the values of these indices. The results were found to be in agreement with ground research.

SummaryChanges of the moisture regime and its influence on the dominance of selected species of small mammal communities were studied in floodplain forests in southern Moravia (river Dyje). In period of typical floodplain regime characterized by groundwater table fluctuation (1968-1972, with high groundwater table level or floods in spring) dominance of Apodemus flavicollis (Mel.) was 42%, Myodes glareolus (Schreb.) 33% and Sorex araneus L. 15% of the total small mammal communities. In period 1982-1987 after cessation of floods by river regulation, rapid groundwater drop and changes in the herb layer, the dominance of Apodemus flavicollis and Myodes glareolus increased. Also the dominance of Apodemus sylvaticus (L.) increased, but that of Sorex araneus collapsed. Further revitalization measures were applied by systems of channels supplying the water to root system of forest trees but not to the herb layer. In 2002-2006 decreasing moisture condition further influenced the dominance of Apodemus flavicollis reaching mean dominance 62%, Myodes glareolus dominance decreased to 20% and that of Sorex araneus remain to be low. All estimated changes were correlated with moisture regime changes and were significant. Thus the changes in the forest moisture regime significantly affect the community of small terrestrial mammals.

South Moravian floodplain forests at the confluence of the Morava and Dyje Rivers, which are related to the floodplain forests of Austria and Slovakia to a considerable degree, have been strongly affected by changes in forest environment caused by natural and anthropogenic impacts. The dominant change factors encompassed changes in the 12–14th centuries resulting in the formation of a flooded alluvium and a significant transition of hardwood floodplain to softwood floodplain. Their further development was affected particularly by forestry activities, and they saw a gradual transformation into hardwood floodplain forests with dominant species of oak, ash, hornbeam, and others. The primary impact in the 20th century was stream regulation and the construction of three water reservoirs, which resulted predominantly in changes in the groundwater table. Response to these changes was registered particularly in the herb layer. The contemporary forest management adjusts to environmental changes and makes efforts to alleviate the negative impacts of previously implemented changes through restoration projects.