Video | Business Headlines | Internet | Science | Scientific Ethics | Technology | Search

 

Come jump in a lake with NIWA


MEDIA RELEASE

FRIDAY, MAY 31, 2019

Come jump in a lake with NIWA


Visitors to NIWA’s stand at this year’s Fieldays are invited to go diving with into the Rotorua lakes -without having to get wet.

NIWA is providing a window beneath the surface of New Zealand’s streams and lakes at Fieldays for people to learn more about our freshwater systems and what keeps them healthy. Through the magic of virtual reality, visitors will take the plunge with NIWA’s specialist divers and swim alongside them as they undertake a survey of underwater plants.

NIWA freshwater ecologist and specialist diver Tracey Burton conducts an underwater survey of plants in Lake Rotomā that gives her an indication of the lake's ecological health. Picture: Rod Budd

The survey is known as LakeSPI (Submerged Plant Indicator) and uses the underwater plants as an indicator of a lake’s ecological health.

LakeSPI surveys have been carried out on 12 Rotorua (Ōkāreka, Ōkaro, Ōkataina, Rerewhakaaitu, Rotoehu, Rotokākahi, Rotomā, Rotomāhana, Rotoiti, Rotorua, Tarawera, and Tikitapu) lakes since 2005 and NIWA freshwater ecologist Tracey Burton says she has seen positive and negative changes.

“Many of the negative changes are attributable to the spread of alien invasive weed species such as hornwort, egeria and lagarosiphon which have had a devastating impact on the some of the lakes. But increased awareness around lake issues and new management initiatives have seen some lakes improve.”

Only two of the 12 Rotorua Te Arawa lakes remain free of major weeds and constant vigilance is needed to prevent the spread of weeds throughout New Zealand’s waterways. This is especially relevant for Lake Rotomā, currently one of the highest ranked lakes in the region.

LakeSPI indicates Rotoma has remained stable with little change for more than 20 years. However just one kilometre to the east is Lake Rotoehu, classified in poor condition, with a heavy infestation of hornwort and water quality issues.

“A piece of weed the size of your thumbnail would be all that it takes for hornwort to be transferred to Rotomā,” Ms Burton says.

“Once in, it would displace the native vegetation in the lake – we’ve already seen this happen in Lake Tarawera and areas of Lake Taupo,” says Burton. “That’s why the ‘check, clean, dry’ message is so important.”

The divers’ observations feed into the national LakeSPI database and build a picture of lake condition and change over the years. The submerged plant indicators help measure two major influences on lake ecology and condition: increased sediments and nutrients and the impact of invasive weeds on native vegetation.

LakeSPI has been used to assess the condition of 305 of New Zealand’s 3,800 lakes, with the data used by the Ministry for the Environment to help describe the state of our freshwater, and it links directly to the Land And Water Aotearoa database (www.lawa.org.nz).

The NIWA Fieldays stand will also house two aquariums – one showing native fish and plants in a good quality environment and the other pest fish and plants in a degraded environment. Scientists will be on hand to discuss to how the health of freshwater environments affects people’s lives.

NIWA ‘s team of weather forecasters will also be at the stand in the main pavilion to answer any questions on the rural climate.

© Scoop Media

 
 
 
Business Headlines | Sci-Tech Headlines

 



The Download Weekly: Vodafone FibreX back in court

Vodafone and the Commerce Commission head back to court over FibreX in a week the TCF issues broadband marketing codes that should avoid similar problems in the future... More>>


NIWA: Tonga Eruption Discoveries Defy Expectations
New findings from the record-breaking Tongan volcanic eruption are “surprising and unexpected”, say scientists from New Zealand’s National Institute for Water and Atmospheric Research (NIWA)... More>>


Commerce Commission: Appeals Record $2.25m Fine In Vodafone FibreX Case

The Commerce Commission has filed an appeal in the High Court against a record $2.25 million fine imposed on Vodafone NZ Limited (Vodafone) for its offending under the Fair Trading Act during its FibreX advertising campaign. While the sentence imposed in the Auckland District Court on April 14 was the largest-ever fine under the Fair Trading Act, the Commission will argue that it is manifestly inadequate... More>>

Stats: Quiet Start For Retail In 2022
The volume of retail sales was relatively unchanged in the March 2022 quarter, following a strong increase in the December 2021 quarter, Stats NZ said today... More>>



Finder: RBNZ Survey: 64% Of Experts Say Rising Inflation Will Push More Kiwis Into Debt

Soaring inflation and cost of living pressures will see many households pushed to the financial limit, according to experts... More>>



Barfoot & Thompson: Rents Up By Around 3% In Most Areas

The average weekly rent paid for homes in most areas of Auckland has risen by around 3 percent year-on-year. The figures for end March from more than 16,000 properties... More>>