Organised by the Rotorua Lakes and Lands Trust (RLLT), the two-day conference heard from scientists and farmers how biological farming is lifting soil and water quality in rural areas.

Conference coordinator Guna Magesan says the high turnout proves bio farming is taken seriously. Magesan, a senior scientist with RLLT, believes bio farming will revolutionalise sustainable farming in New Zealand.

He presented a progress report on the Vallance Project initiated by farmers to improve water quality in Rotorua and Taupo lakes. The project involves conventional and bio farms in Reporoa and Edgecumbe. Twelve drainage-flux meters were used on each farm to measure the amount of drainage and N concentrations in soil water. Monitoring will continue for three years.

In a progress report to the conference, Magesan says the preliminary results are promising. Nitrate concentrations in soil water collected from biological farms are much lower than those collected from conventional farms.

Soil structure is better on biological than conventional farms. The technique may be the answer to nutrient leaching risks faced by the dairy industry, he says.

"New Zealand farmers are under pressure and we need solutions. Biological farming is going to revolutionalise sustainable farming."

A study carried out at Massey University produced similar results. The university in 2001 split its dairy cattle research unit into two farms: organic and conventional. The trial ended in May. Massey's Alan Thatcher told the conference regular monitoring of ground water showed a substantial decline in nitrate leaching from the organic farm.

DairyNZ chairman John Luxton, who opened the conference, noted all farmers in Rotorua catchment areas were involved in projects to reduce nitrate leaching. DairyNZ is also involved. "It's good to see the amount of research going into this," Luxton said.

The dairy industry must be profitable for its 11,500 farmers but it must also be sustainable, he stressed. "It is driven largely by public demand and also by the desire of farmers to be environmentally friendly."