Land conversion checks sought to stem nitrogen loss

Land use change is the most important driver of nitrogen loss to water, according to water quality specialist Rick Pridmore.

Pridmore, originally from California and now DairyNZ’s strategy and investment leader, has been in New Zealand for 35 years and in his current role for seven years.

Addressing about 90 people at the Taranaki Rural Professional Conference which DairyNZ and the NZ Institute of Primary Industry Management hosted at Inglewood last week, he said the conver- sion of land with low nitrogen losses to land that generated high losses should be controlled.

Converting forestry blocks and sheep and beef farms to dairying, as had happened in Waikato, Canterbury and Manawatu caused nitrogen losses from land.

‘‘In Taranaki land use is not changing. Conversion is what’s causing the problem.’’

Intensification and poor practice also drove nitrogen loss. But Pridmore said good environmental practice would not solve water quality issues associated with nitrogen loss; they would not halt the deterioration of water quality if land use change continued unchecked.

As a negotiator with regional councils, he said his role was to maintain and grow the dairy industry. DairyNZ wanted to work constructively with regional councils so nitrogen loss didn’t increase.

‘‘If regional councils think farmers are not trying hard enough, they’ll make the rules harder,’’ he said.

A 2.2 per cent annual increase in milksolids during the next 10 years would create a 27 per cent rise in production.

‘‘To keep our nitrogen footprint the same as today, we need to lower the total nitrogen loss from dairying by 21 per cent.’’

If the industry responded poorly to issues around product integrity and sustainability, consumers, regulators and markets would lose faith in it, leading to a further downward spiral.

The impediments to progress were onfarm skills, the number and skill range of rural advisers and the infrastructure needed to put changes in place.

Improving skills on farms and removing poor practice could yield a one-off reduction of 10 to 15 per cent. Technology and management changes could lower nitrogen loss by 30 per cent.

‘‘There’s $4 billion to be made if we get in synch. We all have to be on the same page.’’

Having been a sustainability adviser to various organisations in New Zealand, he said the dairy industry could become sustainable, although it would take time.

Sustainability should be looked at in terms of New Zealand’s values and its relationship with its markets and consumers and the general public.

But maintaining New Zealand’s high water quality required a united country.

‘‘It’s about bringing the rest of New Zealand with us.’’ he said.