Indigenous forests cover quarter of nation's land

Government science company Landcare Research says it has developed software that allows satellite images of New Zealand to be mined for detailed information on forests.

The Ecosat programme makes satellite pictures easier to interpret, especially where New Zealand's often hilly terrain creates shadows that make computer interpretation of images slow and expensive.

Ecosat "flattens" the effects of topography, so environmental features such as vegetation can be identified more easily.

New maps, derived directly from satellite images, were published yesterday that showed nearly a quarter of New Zealand's land area is taken up by indigenous forest.

When plantation forestry is included, a third of the nation is covered in trees.

Landcare Research's EcoSat forest maps show native forests cover nearly 66,000 square kilometres, 24.8 per cent of the country.

Beech forests are the most widespread, followed by podocarp-broadleaved forests, which include conifers such as rimu, totara and matai, and broadleaved trees like rata, tawa and rewarewa. Exotic forest makes up a further 7.7 per cent of the land area.

Landcare Research scientist John Dymond said the maps revealed the loss of lowland forests nationwide.

- NZPA