13 August 2004
Production drop not necessary for nutrient reduction from farms
For immediate release: Friday 13 August 2004 Rotorua farmers do not necessarily have to drop production to reduce the
amount of nutrients leaching from their properties into nearby streams or lakes, a new report concludes.
The study, by AgResearch, outlines a number of farm management practices that can cut down nitrogen and phosphorus
outputs from a property. They include grazing management, cultivation practices, winter crop management and fertiliser
management.
Environment Bay of Plenty commissioned the study as part of its work for the Rotorua Lakes Protection and Restoration
Action Programme. It did so because of widespread concern that nutrients from agriculture have a role in degrading the
quality of the Rotorua lakes. Called “Land Use Impacts on Nitrogen and Phosphorus Loss and Management Options for
Intervention”, the report was presented to the third meeting of the working party for the Lake Rotorua and Lake Rotoiti
Action Plan last week.
It states that farmers can make a significant difference to nutrient outputs by shortening the time animals spend on
pasture during the winter. In a dairy system, grazing cows off over winter or the use of a feed-pad during winter can
reduce nitrate leaching by up to 60%.
Other more novel approaches show potential but they have not yet been quantified, it adds. In arable cropping, an
important aspect is the timing of cultivation and the presence of a winter cover crop.
At the meeting, the working party also reviewed reports from several focus groups on spring flow diversions, the
diversion of the Ohau Channel outflow, the Ohau Channel groyne and lake water levels and control structures. Rotorua
District Council’s Greg Manzano reported on the Rotorua sewerage scheme upgrade and extensions.
Working Party chairman Bill Cleghorn says very good progress is being made in evaluating some of the urgent actions
required for improving water quality, particularly in Lake Rotoiti.
Other new reports include:
Economic evaluation of water quality induced changes in Rotoiti and Rotorua. (Nimmo-Bell) What would be the impact on
the local and regional economy of land use changes to meet nutrient limits in the Rotorua/Rotoiti catchments? This
report looks at the economic losses from a reduction in land-use intensity. It recognises that pastoral farming,
forestry and tourism are all important economically and suggests options to reduce nutrients going into the lakes should
also aim to minimise economic losses to landowners and the wider community.
Rotorua Lakes: Evaluation of Less Tangible Values (Nimmo-Bell) Lake Rotorua and Lake Rotoiti are valued highly by
people, as the results of this survey show. Some points: The presence of algal blooms affects the use of the lakes for
the majority of respondents. Picnicking is the most popular recreational activity for Rotorua people followed by
swimming then walking and/or photography. About half of the respondents think the government and the polluter should pay
for lake water quality improvement. Over half are not willing to pay. Those who are willing to pay think the lake is
worth preserving “regardless of cost”.
ENDS