NIWA is sponsoring Aquatic Science at the interface, a joint conference for the:
The conference is being held in Hamilton, for more information see the Aquatic science at the interface website
Many New Zealand lakes are under threat due to changes in land-use and invasions of alien aquatic plants. NIWA's LakeSPI (Lake Submerged Plant Indicators) is a bio-assessment tool for monitoring and reporting on the ecological condition of lakes. The LakeSPI website has been updated with improved functionality.
River flows - October to December 2012
The three month map (on the right) shows that most of the North Island rivers are below or far below normal, together with the northern South Island.
The South Island West Coast rivers were normal to below normal, and Southland and East Coast rivers were normal to above normal.
After 150 years of research, one might assume that we have a fairly complete picture of the invertebrate communities in New Zealand streams and rivers. However new research suggests that high altitude streams have distinctly different, poorly-known, biological communities.
The three month flow map (on the right) shows that much of New Zealand experienced normal or above normal river flow conditions.
Intensive land use increases nutrient runoff to rivers, lakes and estuaries with adverse effects on ecosystems. Determining what combinations of land use and management enable the health and services of these ecosystems to be maintained or restored is a major challenge for councils.
Estuary sedimentation is a continual natural process. Land slope, land use, soil type and rainfall all have significant impacts, and form a complex spatial pattern of sediment generation.
River flows - April to June 2012
The three month picture (on the right) shows the extreme dryness across most of the country, and the after effect of a wet April over East Cape and Hawkes Bay.
River temperatures April to June
Autumn river water temperatures were mostly in the range 8 to 16oC and tended to be slightly higher in the north and at lower altitude.