Abstract

  Dutch integral water management aims to restore and maintain healthy aquatic ecosystems, which can sustain most human uses. Clear ecological objectives are necessary. Sustainability of fundamental ecological values (production and yield, species diversity, and self-regulation) is assumed to be best preserved in the reference situation. This is the situation, in which human influence is minimal.
  A general method to present ecological information, the Amoeba approach is discussed. This approach uses selected species as representatives for the ecosystem. Criteria for the selection of species are discussed. For each species (target variable) the current situation, the reference situation, and estimated effects of measures can be found and plotted in an amoeba-like figure. The presentation is a simplification and is therefore easily understood by managers, politicians, and the public. Its application for some Dutch inland waters is discussed.

Keywords: ecology, objectives, water management, Amoeba-approach