The effective management of aquatic resources requires knowledge of when, how much, and why a water body changed from its unperturbed state. Reference conditions are increasingly used to gauge the effects and magnitude of human intervention. According to the WFD, the difference between observed and reference values is expressed as an ecological quality ratio. This simple approach calls for correctly established reference conditions and an understanding of inherent uncertainties.
Several problems emerge, however, in the use of reference conditions. For example, a growing body of literature indicates that classifications based solely on large-scale (e.g., landscape-level) predictors – probably the most common approach to establishing reference conditions for inland surface waters (i.e., typology-based approaches) – cannot capture the fine-scale variability of aquatic communities (e.g., Davy-Bowker et al., 2006; Mazor et al., 2006). In coastal waters, several approaches are used to define reference conditions, for example, low-impact areas, historic data, and modelling.
Reference conditions and class boundaries in WATERS
In WATERS, we will build on the work currently being done in the EU-financed WISER project. The emphasis will be on:
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Establishing reference conditions and setting class boundaries.