Biological trait analysis: application to the Waikato Regional Council Monitoring Programme

Report: TR 2012/04

Author: N Phillips, D Reid (NIWA)

Abstract

As part of the Waikato Regional Council’s Regional Ecological Monitoring of Streams (REMS) programme, metrics based on macroinvertebrate taxonomic composition are used to describe the ecological health of the region’s aquatic resources.

An alternative approach is to use the biological traits of macroinvertebrates, as these reflect changes in ecosystem function rather than just changes in macroinvertebrate composition.

In this project, the response of both metrics and traits to a gradient of pastoral development (% pastoral) for Waikato streams was determined:

•  A priori hypotheses were developed of likely responses of traits to these stressors.
• The effectiveness of metric and trait measures were compared for differentiating levels of impact.
• The potential influence of regional variation in taxonomy on the ability of metrics and traits to detect the impacts of rural development was examined by combining Waikato data with Auckland stream data.
• Finally, the potential use of traits as a mechanistic tool was investigated.

Biological trait analysis: application to the Waikato Regional Council Monitoring Programme [PDF, 1.8 MB]