ILWS - Charles Sturt University
ILWS - Charles Sturt University

Blue-green algal monitoring in the Edward-Wakool River System (2016)

Strategic Research Area

Sustainable Water

Funding

Commonwealth Environmental Water Office (CEWO), $106,476

Researchers/investigators

Professor Robyn Watts, Dr Julia Howitt, & Dr Nicole McCasker   

Description

Algal bloomIn the first half of 2016 there was a massive blue-green algal bloom along the Murray River, which, at its peak, ran the length of the Murray from Lake Hume to past Wentworth (1630kms) causing much economic hardship for primary producers, tourist operators and businesses alike.

The species of naturally occurring cyanobacteria, Chrysosporum ovalisporum, which caused the bloom occurs elsewhere in Australia and the world. It is usually a minor component of a blue-green algal bloom, not the dominant species. However the higher than average temperatures in March are thought to have exacerbated the bloom's growth and spread.

In an example of 'value-adding to existing research' Institute researchers already monitoring ecosystem responses to Commonwealth water in the Edward-Wakool River System as part of a five year project funded by CEWO were contracted by CEWO to do additional weekly monitoring for the life of the bloom in the Edward-Wakool. (Twelve weeks from the beginning of March to the end of May.)

Water samples, collected by the team, were analysed for various parameters at CSU laboratories in Wagga and Albury, Monash University in Melbourne, and ALS Environmental Laboratories in Canberra. While monitoring of the bloom was done by other organisation, it was not done to the same intensity as in the Edward-Wakool. The result is the most detailed dataset available on the bloom; a unique dataset that includes detailed water quality and river metabolism (a measure of how much productivity and photosynthesis is occurring in the river) before, during and after the bloom.

The dataset includes weekly nutrient data, weekly dissolved organic carbon data and measurements of dissolved oxygen levels every 10 minutes.  Three main findings so far are:

  • The concentration of nutrients changed dramatically as the bloom progressed
  • The bloom grew to different extents in different parts of the system
  • The bloom was a controlling influence on how much dissolved oxygen was in the system

While the bloom was in progress the researchers were in regular contact with water managers and CEWO. The data collected was shared with the Murray Regional Algal Coordinating Committee, the Murray Dissolved Oxygen Group, Murray Irrigation Limited, the Murray Darling Basin Authority, and others agencies involved in water delivery. The researchers also compared their data with data from the other monitoring programs.

Outputs

Presentations (by Prof Watts) to the Wakool River Association March14.

Howitt, J., Watts, R. & McCasker, N. (2016) Effects of the 2016 algal bloom in the Edward/Wakool river system- a preliminary analysis, presented at the Prediction of Harmful Algal Blooms workshop, CSIRO Land and Water, Canberra, June 23-24

Howitt, J., Watts, R. & McCasker, N. (2016) Effects of the Chrysosporum ovalisporum bloom on water quality in the Edward-Wakool system - comparison with Long Term Intervention Monitoring data. Presented at the Australian Society for Limnology Conference, Sept 26-30, Ballarat. 

LTIM Algal Monitoring Progress Report 1. March (PDF)

LTIM Algal Monitoring Progress Report 2. (March)

LTIM Algal Monitoring Progress Report 3. March (PDF)

LTIM Algal Monitoring Progress Report 4. May (PDF)

Outcomes

The information collected by the researchers:

  • contributed to the day-to-day decisions made by water managers during the bloom
  • by improving knowledge about blue green algal blooms and the environmental factors that influence them, is providing important information for future water management decisions.

Contact

Professor Robyn Watts

Albury-Wodonga campus

Email

Dr Julia Howitt
Wagga Wagga campus

Email 

November 2016