Master Thesis

The Convention on Biological Diversity (CBD) adopted at the United Nations Conference for the Environment and Development 1991 in Rio de Janeiro dates now back nearly two decades. 189 countries and the European Union have since acceded to the Convention on Biological Diversity. One of the CBD’s core goals is to stop the loss of global biological diversity by 2010. In the preface of the 9th Conference of the Parties (COP) to the Convention on Biological Diversity in 2008 hosted in Bonn, Germany, numerous calls highlighted the still ongoing loss of biodiversity. The European Environmental Agency states that ’Europe is currently suffering from a steady loss of biodiversity’ (European Environmental Agency 2008). However, after a long time of theoretical discussions there is neither a satisfying way to measure all properties of biological diversity - or ’biodiversity’ - nor a possibility to compare these components among different spatial and temporal scales. In the present thesis different aspects of biological diversity will be examined. After introducing historic developments of biodiversity research (section 1), a special focus is laid on available measurement techniques for species diversity (section 2). Their strength and weaknesses will be discussed. Two case studies will contribute to the vivid discussion on this field of science: The influence of rare and common species on a multitude of different similarity indices in general and on the distance-decay relationship in particular will be analysed (section 3). Questions of sampling scale are addressed (section 4) and a final discussion and outlook is given (section 5).