The “De Putten” site is a complex of low-lying meadows in the polders of the Scheldt between Doel and Kieldrecht (Belgium). The grasslands are brackish and very wet. These conditions has resulted in a very specific, valuable vegetation which makes the area very important for some rare species of breeding birds. It is why Belgium has indicated the “De Putten” as an area important for the preservation of birds in accordance with the bird’s directive (7/409/EEC). Because of the development of the Waasland port in the vicinity, “De Putten” will be disappear in future under some meters sand. Before Belgium can do this, it has to take compensational measures for the loss of the “De Putten” as is write down in the same bird’s directive. This must lead to the creation of a likely habitat in the direct environment of the former location. Two areas are considered for this compensation: the nature area “Drijdijk” and the agricultural area with a valuable landscape in the north of the Prosperpolder.The objective of this study is to see which specific, non-biotic circumstances are present in “De Putten” and to see if we can create them in the areas formerly mentioned. So, we must in fact show if it is possible to create an area with a very likely hydrology to compensate for the loss of the “De Putten” and when this is possible, we have to say how this must be done.For the execution of the project, we have divided it into five parts:1) a detailed study of the groundwater and the surface waters: as well the quality as the quantity;2) a detailed study of the soil, more specifically the texture and the fertility;3) a study of the vegetation (species richness and content);4) an experiment to study the colonisation of typical plant species;5) an analysis of the seed-bank.At the end, we will have, apart from a decision on the compensation, the following five results:1) insight into the typical hydrology of “De Putten” and other polder-grasslands on the left bank of the Scheldt which make them so special for nature;2) a detailed species list (plants and some animals);3) an idea of how a former, nutrient rich field will be develop into a valuable wet meadow on a brackish soil;4) the potential species richness;5) spatial integration of the possible alternatives with nature areas (existenting or developing) in the neighbourhood