17 October 1996 New laboratory at Lincoln puts focus on tree ecology

A Tree-Ring Laboratory is being established at Lincoln University as a focus for tree ecology studies and within it a state-of-the art analytical system may soon open a "window" of time stretching back thousands of years for scientists seeking an accurate picture of New Zealand's climatic history.

Funding from the New Zealand Lottery Grants Board plus money from the University itself has given a green light to the $76,000 purchase of an automatic, interactive image analysis system, WinDENDRO, specifically designed for tree­ ring and other tree related measurements.

"Plant ecology at Lincoln is in a strong position," says Dr Jonathan Palmer of the Department of Plant Science, one of the prime movers behind the WinDENDRO purchase and the setting up of the laboratory.

"With the presence of committed teachers and researchers such as Dr Glenn Stewart, Dr Richard Duncan, Dr David Given, Dr Don Mead and others, Lincoln is well positioned for a leadership role in tree ecology studies."

In establishing the laboratory at Lincoln University, the intention is also to enable Landcare plant ecologists, located near the campus, to use the equipment and participate in collaborative research.

Dr Palmer's own research interest lies in the use of tree-rings to unlock information about past climate patterns.

"A reconstruction of New Zealand's climate over the millennia is essential for understanding the situation today," he says. "In the absence of written records, tree rings offer the best means of reconstructing past climate information, right down to intra-seasonal levels," he says.

"We have to know what happened in the past in order to determine accurately whether the changes and variations in the current climate, covered by the short period for which written records exist, are the result of 'natural' or human-related influences."

Others at Lincoln are interested in the age of trees in relation to forest population and management studies – it's essential to know how old trees are before you can start to answer management questions – and still others, such as Dr Don Mead and those involved with the University's agroforestry trial, are keen to use the system's root analysis facility.

Initially Lincoln's Tree-ring Laboratory and the WinDENDRO system will be concerned with two major studies. The first is an international radiocarbon calibration project in association with Waikato University and Queen's University, Belfast. This project concerns the issue of disparity between Northern Hemisphere and Southern Hemisphere radiocarbon datings and the desire to finally establish if there is a systematic 40-year difference between the two.

The other study involves looking at kauri in Northland. Slabs of ancient swamp­ preserved kauri – some lying buried for as long as 40,000 years – will be analysed to yield information on climate change over their lifetime as living trees which, in some cases exceeds 1000 years.

With a Tree-Ring Laboratory and data gathering operation on the Lincoln campus, the University will be in a position to provide information to the International Tree Ring Databank at Boulder, Colorado, and Dr Palmer sees this as an important obligation.

"The Southern Hemisphere, being largely ocean, is a 'data poor' region, so countries like New Zealand become very important in the collection of information," he says. "Here at Lincoln we look forward to making an international contribution to assist the work of other scientists and global climate modellers."

Ian Collins, Journalist, Lincoln University, Canterbury, New Zealand.