Indicators of ecological condition

Conventional biological measures for monitoring aquatic ecosystem health, such as macroinvertebrates, can be difficult to apply in large rivers. These difficulties include obtaining representative samples, and limited understanding of factors affecting macroinvertebrate distribution and abundance in large rivers. Alternative measures such as the rate of organic matter decomposition and river metabolism offer potential for monitoring the ecological condition of large rivers. CBER collaborators Roger Young and Joanne Clapcott of the Cawthron Institute, Nelson, have been testing the application of cotton strip breakdown rates and measures of gross primary production and ecosystem respiration as indicators of large river health.

Figure 1. Changes in dissolved oxygen saturation over a 24-hour period in the Waikato River at Hamilton Gardens (April 2008).

Current projects

Testing functional indicators for monitoring the ecological condition of large rivers (Roger Young & Joanne Clapcott, Cawthron Institute).
Macroinvertebrate indicators for non-wadeable rivers (Kevin Collier).

References

Clapcott J, Young R 2009. Spatial and temporal variation of functional indicators in Waikato rivers. Prepared for Environment Waikato. Cawthron Report No. 1693. 24 p.

Clapcott J; Young R 2008. Spatial variation of functional indicators in the Waikato River. Environment Waikato technical report no. 2008/32. Cawthron Institute, Nelson. Read report