Oxbow A former meander of a river, which is cut both upstream and downstream sections from the main stream. The oxbows are on the way of natural eutrophisation, with very specious and unique habitats.
Bottom weir

It keeps back water in riverbeds, or in oxbows, and increase the average water levels of the water body. It is a sill on the bottom of the bed of the oxbow, or of the riverbed. They are typical water retention artefact, which usually have positive impacts on habitats upstream from them, but may have negative effects if designed poorly, and they block longitudinal way of migration.

UNESCO Biopshere Reserve  Biosphere reserves are areas comprising terrestrial, marine and coastal ecosystems. Each reserve promotes solutions reconciling the conservation of biodiversity with its sustainable use. Biosphere reserves are ‘Science for Sustainability support sites’ – special places for testing interdisciplinary approaches to understanding and managing changes and interactions between social and ecological systems, including conflict prevention and management of biodiversity. Biosphere reserves are nominated by national governments and their status is internationally recognized. There are more than 600 biosphere reserves in 119  countries, including 14 transboundary sites.
Side-arm It is a meander of a river, which receives water supply from the river, but only during high water periods. Many side-arms were artificially cut from rivers in the 20th century, which reduced the dynamism of living rivers.
Riverbed degradation Due to river regulation measures, the dynamism changes of natural riverbeds are blocked. Riverbed degradation means that there are embankments, fixed riverbanks, the meandering capacity of the rivers are low. Due to the lack of sediments the riverbed incision are usually significant, and the communication between rivers and floodplains are degrading.
Native species  Species, which are characteristic members of habitats, and which are the optimum of the hydrological, geographical, etc circumstances.
LIFE+ Nature program

The European Union financial instrument for supporting the maintenance and improvement the status of Natura 2000 species and habitats.

Natura 2000 The network of European importance habitats and species, which were established by the Bird and Habitat Directives of the EU. 
Kriznica This is the village, which is between the main stream of Drava and the Old-Drava oxbow, on the Croatian side of the project area.
Water retention structures Different types of artefacts, which are built from the purpose of water retention on the active, or morphological floodplain of rivers, or in riverbeds., oxbows and side-arms.