HP8 Field Biological Monitoring of Ecosystem Impairment
A105 & A106
1:20 PM - 5:20 PM, Thursday
() Use of ordination techniques to analyse multivariate time series from biomonitoring studies.
van den Brink, P.J.1, den Besten, P.J.2, 1 Alterra, Wageningen, The Netherlands2 Institute for Inland Water Management and Waste Water Treatment (RIZA), Lelystad, The Netherlands
ABSTRACT- Chemical and biological monitoring are often performed to evaluate the quality of surface waters for regulatory purposes and/or to evaluate environmental status and trends. In Europe these monitoring activities are expected to increase due to the Water Framework Directive, as adopted on 23 October 2000 to establish a framework for the Community action in the field of water policy. For surface waters this framework defines good ecological and chemical status, which needs to be monitored in time. The resulting biological and chemical data sets are large and difficult to evaluate. Since long multivariate techniques are used to analyse complex data sets. This paper will evaluate the methods currently used and introduces a new method that overcomes the cluttered graphical representation of the results, which is a great drawback of most conventional methods. To illustrate this, two example data sets are analysed with two ordination techniques. Redundancy Analysis is used to present an overview on the coupling of chemical and biological data, the Principal Response Curves technique is used to show trends in time with an internal or external reference (e.g. desired water quality). Advantages and disadvantages of both methods are discussed and compared with conventional methods (e.g. diversity indices and Principal Component Analysis).
Key words: Principal Response Curves, Redundancy Analysis, Water Framework Directive, Statistical Analysis