Nature conservancy significance of the Drava River
The stretch of the Drava between Maribor and the border at Središče ob Dravi has the character of a lowland river. In this particular area the Drava is, with its riparian zone, a true treasure trove of biodiversity and therefore one of the most significant nature conservation areas in Slovenia. With its flow, it creates diverse living environments, which alternate in a relatively small area and at the same time constantly change owing to the river’s functioning. The Drava River area is part of the European ecological network Natura 2000. The Drava and the areas along it are stipulated not only as Natura 2000 protection areas, but also as protected areas and valuable natural features.
Why are the habitats of many endangered species in and along the Drava in an unfavourable condition?
With the consolidation of banks and hydroelectric power use of the Drava River, the intensity of hydromorphological processes has been notably reduced. The former natural shifting of the riverbed, the formation of backwaters, oxbow lakes and river inlets has practically stopped. Owing to the changed flow regime and the large amount of silt deposited during high waters and notable groundwater decrease, the former backwaters, oxbow lakes and depressions are becoming increasingly silted, dry and overgrown. As the hydroelectric dams are impassable for gravel, gravel shifting has also been drastically reduced. As a result, the intensity of gravel formation and shifting of gravel banks has been significantly reduced, too; at the same time, the latter are becoming extremely quickly overgrown with vegetation. Furthermore, water retention efficiency is declining during floods as well.
The hydrological and hydromorphological changes described above also have an impact on forests, where rejuvenation with locally characteristic indigenous tree species is often no longer taking place. Due to trends in either intensification or abandonment of agricultural use, the extent and favourable conservation status of grassland habitat types is also decreasing, with the habitat of species related to the cultural landscape deteriorating at the same time