Survey helps scientists learn about waterways

Riparian planting areas need to be at least 10m wide on each bank to have a beneficial effect on stream water quality

This is just what NIWA and DairyNZ are asking anyone who has planted along stream banks to do - log on at riparian.niwa.co.nz to formally record their work.

The online survey takes five minutes. It will form the basis of the National Riparian Restoration Database, which will help scientists to improve understanding of how riparian buffers benefit waterways.

This project is about what has been done to date, with the focus on sites more than five to 10 years old.

It is separate to DairyNZ's riparian planner which assists with the work of installing riparian buffers, including mapping out, budgeting and recording actions. This is at riparian-planner.dairynz.co.nz

We want to know the extent of existing riparian projects across the country."

Aslan Wright-Stow

Riparian buffer strips are created by fencing to keep animals out and let grass grow long, as well as being planted.

The long grass and plantings, usually of native species, filter, take up or transform nutrients, sediment and faecal pathogens before they can reach waterways. They also stabilise streambanks, enhance biodiversity and cool streams - improving stream health and resilience.

Freshwater scientists Aslan Wright-Stow (DairyNZ) and Richard Storey (NIWA), who were both involved in setting up the National Riparian Restoration Database, have found that many riparian projects lead to rapid ecological recovery in streams, while others need longer to deliver all the benefits.

"Although we know a lot about how riparian buffers work, there are not many New Zealand case studies showing, for example, how long and wide a riparian buffer needs to be, or where it should be located along the river network, to get the greatest improvements in stream health," Dr Storey says.

"The survey information we collect will help us determine which characteristics of riparian buffer strips are most effective in improving water quality and stream health."

"We want to know the extent of existing riparian projects across the country," Mr Wright-Stow says.

"Much riparian restoration work has been undertaken over many decades. We can use these projects to learn from, and help guide future riparian planting design, feeding the findings back into the riparian planner for even better outcomes."

Once the database is underway, the next step will be selecting about 50 sites around the country, and monitoring them over a period of 12-18 months - work that 'citizen scientists', members of the public, will be invited to help with.

NIWA will provide training and equipment. The citizen scientists will take measurements of stream life, water quality and the physical habitat, as well as recording some of the characteristics of the planted riparian area.

They will then put the data onto a website where it will be evaluated by scientists at NIWA and DairyNZ. Mr Wright-Stow says this will be an interesting project, and not arduous.

"All citizen scientists need to commit to is about two to three hours a month over a period of 12 to 18 months. People keen to get involved in this project can find out more at riparian.niwa.co.nz and register their interest there."