Enhancing bioassessment approaches: development of a river services assessment framework.

There has been a trend toward increasing anthropocentrism in definitions of river health through the explicit inclusion of societal valuation of ecosystem services provided by rivers. New frameworks and associated indicators of river health are therefore required to centralize ecosystem services within river assessment and management activities. Here, we adopt an anthropocentric conceptualization of rivers to focus on a river's ability to maintain ecological function and structure that support ecosystem services valued by society. We apply this approach to further existing conceptual models of river assessment by identifying how benthic indicators can be linked to valued ecosystem services in a river services assessment framework. This approach extends bioassessment from a focus on assessing departure from reference condition to also include the evaluation of rivers based on their delivery of ecosystem services. Indicators based on benthic processes and assemblages are widely used in river health assessments; thus, these are reviewed to identify those indicators most closely linked with the provision of river ecosystem services. Finally, we illustrate how our approach can be applied to management through contrasting watershed examples, including a highly modified agricultural region and relatively pristine Arctic watersheds. The proposed approach supports an explicit connection between valued ecosystem services and benthic indicators, providing more targeted assessment results for use in river management decision-making. [ABSTRACT FROM AUTHOR]