Recente vondsten van breedbladige fonteinkruiden (Groenlandia en Potamogeton spec.) in de provincie Noord-Brabant

Since 1987 the distribution of many plant species in the central and eastern parts of the province Noord-Brabant has been mapped for country use planning by the Provincial Authorities. Distribution maps (with a 5 x 5 km² grid) of the Potamogeton (broad-leaved pondweed) species, which are important indicators of water quality, are presented and compared with data of previous periods. It is obvious that several Potamogeton species suffered a decline, whereas others have increased. Potamogeton nodosus, a species so far restricted to large rivers, turned up at considerable distance from a river as a side-effect of water-intake from the river Meuse, meant to restore the local desiccation. Potamogeton praelongus was recorded in this province for the first time since 1920.