A multimetric approach for predicting the ecological integrity of New Zealand streams

Integrating multiple measures of stream health into a combined metric can provide a holistic assessment of the ecological integrity of a stream. The aim of this study was to develop a multimetric index (MMI) of stream integrity based on predictive modelling of national data sets of water quality, macroinvertebrates, fish and ecosystem process metrics. We used a boosted regression tree approach to calculate an observed/expected score for each metric prior to combining metrics in a MMI based on data availability and the strength of predictive models. The resulting MMI provides a geographically meaningful prediction of the ecological integrity of rivers in New Zealand, but identifies limitations in data and approach, providing focus for ongoing research.

[1]  John L Stoddard,et al.  Setting expectations for the ecological condition of streams: the concept of reference condition. , 2005, Ecological applications : a publication of the Ecological Society of America.

[2]  Jane Elith,et al.  Use of generalised dissimilarity modelling to improve the biological discrimination of river and stream classifications , 2011 .

[3]  P. Verdonschot,et al.  Towards a multimetric index for the assessment of Dutch streams using benthic macroinvertebrates , 2004, Hydrobiologia.

[4]  D. Carlisle,et al.  Biological assessments of Appalachian streams based on predictive models for fish, macroinvertebrate, and diatom assemblages , 2008, Journal of the North American Benthological Society.

[5]  J. Karr.  Assessment of Biotic Integrity Using Fish Communities , 1981 .

[6]  M. Schallenberg,et al.  Approaches to assessing ecological integrity of New Zealand freshwaters , 2011 .

[7]  R. Death,et al.  Application of the Index of Biotic Integrity Methodology to New Zealand Freshwater Fish Communities , 2004, Environmental management.

[8]  R. King,et al.  A new method for detecting and interpreting biodiversity and ecological community thresholds , 2010 .

[9]  U. Uehlinger.  Resistance and resilience of ecosystem metabolism in a flood-prone river system , 2000 .

[10]  R. J. Stevenson,et al.  Use of periphyton assemblage data as an index of biotic integrity , 2000, Journal of the North American Benthological Society.

[11]  Leo Breiman,et al.  Random Forests , 2001, Machine Learning.

[12]  Agricultural disturbance response models for invertebrate and algal metrics from streams at two spatial scales within the U.S. , 2014, Hydrobiologia.

[13]  D. Goffaux,et al.  Assessing river biotic condition at a continental scale: a European approach using functional metrics and fish assemblages , 2006 .

[14]  R. Hughes,et al.  A process for developing and evaluating indices of fish assemblage integrity , 1998 .

[15]  John R. Leathwick,et al.  Quantifying relationships between land-use gradients and structural and functional indicators of stream ecological integrity , 2012 .

[16]  F. Sabater,et al.  Meteorological and riparian influences on organic matter dynamics in a forested Mediterranean stream , 2007, Journal of the North American Benthological Society.

[17]  M. Barbour,et al.  Assessment framework for mid-Atlantic coastal plain streams using benthic macroinvertebrates , 2000, Journal of the North American Benthological Society.

[18]  J Elith,et al.  A working guide to boosted regression trees. , 2008, The Journal of animal ecology.

[19]  Robert M. Hughes,et al.  A process for creating multimetric indices for large-scale aquatic surveys , 2008, Journal of the North American Benthological Society.

[20]  Other.  Directive 2000/60/EC of the European Parliament and of The Council of 23 October 2000 establishing a Framework for Community Action in the Field of Water Policy (Water Framework Directive) , 2000 .

[21]  James R. Karr,et al.  Assessing Invertebrate Responses to Human Activities: Evaluating Alternative Approaches , 1996, Journal of the North American Benthological Society.

[22]  C. Hawkins,et al.  Modeling natural environmental gradients improves the accuracy and precision of diatom-based indicators , 2007, Journal of the North American Benthological Society.

[23]  K. Collier.  Average score per metric: An alternative metric aggregation method for assessing wadeable stream health , 2008 .

[24]  A. H. Bell,et al.  Urban streams across the USA: lessons learned from studies in 9 metropolitan areas , 2009, Journal of the North American Benthological Society.