Freshwater quality

Dissolved oxygen (DO) is a relative measure of the amount of oxygen (O2) dissolved in water.

A high proportion of New Zealand’s native freshwater fish fauna need to migrate to and from the sea.

NIWA provides national capabilities in Water Quality Monitoring.

Nutrients in waterways are essential for the growth of algae and aquatic plants but too much can destroy an ecosystem.

The condition of many NZ lakes is under threat from land-use changes and the invasion of alien aquatic plants.

Waterways can easily become contaminated by pathogens when effluent is discharged nearby.

Submerged plants have a number of advantages that favour their use as indicators of lake ecological condition.

In Kaitiaki Tools the term mahinga kai generally refers to indigenous freshwater species that have traditionally been used as food, tools, or other resources.

Banded kōkopu juveniles are very good climbers and will try to escape from buckets by clinging to and wriggling up the sides.

When soils erode, sediments are washed into waterways.