Algal Problems Related to the Eutrophication of European Water Supplies, and a Bio-Assay Method to Assess Fertilizing Influences of Pollution on Inland Waters

Abstract

It has been said that Europe is almost as complicated physically as it is politically. Although the European continent is the smallest principal division of the land surface of the globe distinguished by this term, the area still amounts to more than 10 million km2. Situated between 71 °N (Norway) and 36°N (Spain) and from 9°W (Portugal) to 66°E (Ural), deeply penetrated by the sea and with several great mountain ranges, the consequence is an outstanding variation in physical features and climatic contrasts. The hydrographic relations are correspondingly varied. The openness of Europe to oceanic influences and the topography give the landscape a multiplicity of rivers and lakes. But there are also great areas with small amounts of annual rainfall and with surface waters of sparse occurrence. Generalizations are misleading, but it is not wrong to state that almost all types of aquatic biotopes are represented, giving support to the most varied types of algal communities.