Clever college students pull ground from under experts

Waihi College students told two Government select committees today how their "kitchen science techniques" have revealed data on soil carbon that experts said was too expensive and difficult to produce.
Via video conferencing, seven of the college's Year 10 students presented the finding of nearly two years' research to the Primary Production Select Committee and the Emissions Trading Scheme Review Committee.
Together with other 14-year-olds, the students have used a modified barbecue to discover the amount of carbon in soils from three different land uses, kiwifruit, dairying and maize growing.
"Basically these students have done what government advisers said was too difficult, expensive and time consuming to achieve," said the college's farm unit manager and retired dairy farmer Clyde Smith, who oversaw much of the research.
The select committee presentations were a result of representations made by Dr Peter Brumby, a former adviser to the World Bank on agricultural biotechnology and Max Purnell, of the Agricultural and Marketing Research and Development Trust (Agmardt).
Dr Brumby assisted the students as a scientific advisor and Agmardt has helped fund the project. Soil samples were taken from a Whangamata site where a kiwifruit orchard, a dairy farm and a maize crop share a common boundary. Those samples were dehydrated in ovens in the college's home economic room, weighed and then heated to about 450 degrees on a barbecue, reducing them to fine powder, and weighed again. The different in weight is due mainly to the loss of carbon.
Significantly more carbon was found in samples from the kiwifruit and dairy farm soils than from the maize paddocks, demonstrating that orchards and pastoral farming leave more carbon in the soil than cropping.
Mr Smith said the side-by-side land use meant results were from the same soils, "and the results showed a carbon content of 25 per cent in both the dairy farm and kiwifruit orchard and 17 to 18 per cent in the maize paddocks".