Biomanipulation in the Netherlands : 15 years of experience

Up to the mid 1950's Dutch lakes were characterised by clear water and luxurious macrophyte growth. In the 1960's eutrophication changed this situation and the lakes suffered from cyanobacterial blooms, turbid water and poor submerged vegetation. Restoration programmes were aimed at reducing the rates of the external phosphorus loading. Due to these measures, the nutrient- and chlorophyll-a concentrations decreased. The transparency of the water, however, increased only slightly. In the past one decade it has been recognised that eutrophication had given the turbid state various stabilising me... Mehr ...