Mapping tech holds promise

Tue, 28 April 2015 ppp

Charles Parkinson

Archaeologist Damian Evans gestures at the Beng Mealea temple complex in Siem Reap province in May 2013, when he revealed that the ancient city of Angkor was larger than believed through a remote sensing laser survey. Scott Howes

Aerial mapping techniques used to produce two new studies into forest canopies around the Angkor temple complex could provide a major boost to future conservation efforts in Cambodia and other tropical countries.

The first of the studies combined very high resolution (VHR) imagery with plant field data, while the second combined VHR imagery with images taken from Google Earth to produce detailed maps of the tree species in the Angkor Thom complex.

According to the studies' authors,, the methods could be used to monitor the presence of endangered or protected tree species, as well as to produce accurate estimations of the quantity of timber present in forests – data essential to implementing incentive-based conservation schemes such as the Reducing Emissions from Deforestation and Forest Degradation (REDD) program.

"In a few hours of flying, we can collect data over hundreds of square kilometres that would take decades to acquire on the ground,” said Dr Damian Evans, one of the reports' authors.

According to co-author Minerva Singh, previous methods for producing such maps were not only much more time-consuming, but processing the results could be very expensive, with both factors potentially detrimental to conservation efforts.

“By the time you have processed the data, you could have lost a couple of endangered species,” she said. “This could be a boon for tropical countries such as Cambodia.”

For Evans, who in 2013 discovered a new ancient archaeological site in Cambodia using aerial laser technology, the work reinforces the relationship between such sites and the surrounding natural environment.

“Not only does it contribute to the aesthetics and the economic value of the site, but it also plays a significant role in preserving the monuments and maintaining the complexity and diversity of the area,” he said.

The results have drawn praise from the Apsara Authority, which lauded their potential to support REDD and other conservation schemes.

“The results obtained by this technology are beyond our expectations,” said Apsara’s deputy director-general Tan Boun Suy.

Meanwhile, international organisations involved in forest conservation welcomed the possibility of the techniques assisting the battle to conserve forests and endangered species in Southeast Asia and elsewhere

“We are very interested and welcome such studies,” said Arie Soetjiadi, a coordinator at the Rainforest Alliance.

And while the possibilities for forest conservation are huge, according to Evans, their full applicability in addressing climate change is yet to be explored.

“We are really just starting to scratch the surface here,” he said.