- The judges praise the winning methodology’s versatility, speediness and accuracy in mapping peatlands.
- Indonesia will have two years to fully adapt the winning methodology into the new peat-mapping standard, although some government agencies are clamoring to start adopting the system immediately.
JAKARTA — A team of scientists from Indonesia, Germany and the Netherlands has won a competition two years in the making to come up with a fast, accurate and cost-effective way to map Indonesia’s vast tropical peatlands — an all-important carbon sink that the government wants to conserve.
The winner of the $1 million Indonesian Peat Prize, funded by the David and Lucile Packard Foundation, was announced Feb. 2 to coincide with World Wetlands Day, two years after Indonesia’s Geospatial Information Agency (BIG) launched it to select a mapping proposal to serve as the standard for surveying the country’s peatlands.
“The BIG is pleased and excited that the prize has produced the best method for mapping peatland that combines accuracy, affordability and timeliness to support the BIG’s work in mapping and providing geospatial data and information,” agency chief Hasanuddin Zainal Abidin said at the announcement in Jakarta.
The winner, the International Peat Mapping Team (IPMT), boasts members from Germany’s Remote Sensing Solutions GmbH (RSS), Indonesia’s state-funded Agency for the Assessment and Application of Technology (BPPT), and Sriwijaya University in South Sumatra province.
The BIG will have two years to fully adapt their methodology into the new peat-mapping standard, although some government agencies are clamoring to start adopting the system immediately.
The IPMT proposal combines satellite-based technologies and the airborne high-resolution mapping technique known as lidar — which involves beaming laser pulses at the ground from a plane and recording the reflected rays — with on-the-ground measurements.
The team started off with German radar technology, called WorldDEM, that uses satellite imagery to model terrain at a 10-meter (33-foot) resolution, as well as imagery from the Sentinel series of Earth-observation satellites. The team then used lidar to calibrate and verify the results from WorldDEM. Finally, to accurately estimate peat thickness, the team used on-the-ground measurements.
“Our methodology can support work to acquire the topographic elevation data on the country’s peatland, including dome-shaped peatland, that can be used to understand the groundwater level and other hydrological purposes,” said Bambang Setiadi, a member of the team from the BPPT, who is also chairman of Indonesia’s National Research Council.
Some of the technologies and methods are not new, such as lidar, which was also proposed by other finalists as well as the Indonesian government.
However, it was the team’s decision to combine the various methods that was hailed by the judges. Supiandi Sabiham, co-chair of the competition’s scientific advisory board, said the combination of these methods gave the IPMT the edge over the other finalists, especially on accuracy.
“While the cost [of the winning method] is relatively higher, its accuracy is better,” he told reporters after the announcement. “That’s why we agreed to declare the team as the winner.”
Supiandi said the cost of mapping peatlands using the winning method would be $1 to $6 per hectare (40 cents to $2.43 per acre). With an estimated 14.8 million hectares (36.6 million acres, or 57,150 square miles) of peatland across Indonesia, a balance between cost and effectiveness was an important factor in selecting the winning proposal.
Other finalists came in lower on price. The joint team from Deltares, a Dutch consultancy with expertise in wetlands issues, and Indonesia’s Bandung Institute of Technology (ITB) applied an elevation model created from airborne lidar data and limited field measurements of peat thickness.
By only flying across transects, and not going full coverage, the team was able to reduce the lidar cost by a factor of 10 while still maintaining the accuracy of the elevation model within 0.5 meters (1.6 feet) for at least 95 percent of the mapped area.
As of the end of 2017, Deltares had collected lidar data for much of eastern Sumatra’s lowlands and parts of West Kalimantan province, in Indonesian Borneo, covering more than 60,000 square kilometers (23,170 square miles) of landscape. Most of that area is peatland, and of the total, a third was surveyed using lidar.
The funding for Deltares’s mapping came from several donors, including Indonesia’s largest paper producer, Asia Pulp and Paper (APP); the U.K. Climate Change Unit (UKCCU); and the Norwegian Agency for Development Cooperation (Norad).
Though it didn’t win the prize, Deltares said in a statement that its method of cutting the lidar cost could be adopted by the winning team. Deltares also plans to contribute to the national peat-mapping effort by releasing the maps it has already created for APP and publishing its methods in scientific journals.
The winners, meanwhile, earned praise for the versatility of their proposed method — ranging from full lidar coverage at the top end, to partial lidar, to the WorldDEM database and finally satellite imaging at the budget end of the scale — to suit the topography and condition of the areas to be mapped.
“It’s an advantage because Indonesia’s natural environment and peat is very varied. That’s why we need several alternatives that can be applied,” said Supiandi, who is also the head of Indonesia’s Peatlands Association.
The IPMT’s method was also cited for its speed. The BPPT’s Bambang said it was used to map more than 140 square kilometers (54 square miles) of peatland in Kubu Raya district in West Kalimantan and Bengkalis district in Riau province in five days.
Winning method to be adopted
While the IPMT now has up to two years to fully flesh out the method as the official mapping standard, the BIG wants to start adopting aspects of it immediately, citing the pressing need for a comprehensive and detailed map of the country’s peatlands.
Currently, two peat maps among several in existence are the most commonly used: one produced by the NGO Wetlands International in 2004, and the other by the Ministry of Agriculture in 2011. In a 2013 report, Deltares concluded that neither of these maps was suitable for spatial planning or policymaking, as both consistently underestimated the extent of the peatland and thickness of the peat layers.
The Ministry of Environment and Forestry also published a peat hydrological area map in 2017, which divides peat zones into two categories: protection or production. The map uses data from various official maps, including that of the Ministry of Agriculture and one from the Ministry of Public Works.
But at a scale of 1:250,000, the Ministry of Environment and Forestry’s map is not sufficiently detailed for use in effective spatial planning and policymaking tasks, which require maps with a finer resolution of 1:50,000.
This lack of an authoritative map and poor data has made it difficult for the government to identify peat areas that needed to be conserved — the necessary first step toward rehabilitating peatlands that have been degraded and rendered susceptible to fires. It has also allowed large swaths of peat forest to be included in plantation leases, whose holders typically drain and burn the land for planting.
The urgency of mapping Indonesia’s peat is focused not just on delineating areas of peatlands, but also determining the depth of the peat layer: the deeper it is, the greater the potential ecological damage, including carbon emissions, should it be disturbed.
“After looked more closely at our existing peat maps, there’s indeed a limitation because we haven’t mapped the depth of the peat,” said BIG deputy head Nurwadjedi. “That’s why we need to upgrade [our maps].”
Another agency eyeing the immediate adoption of the IPMT method is the presidentially appointed Peatland Restoration Agency (BRG), which plans to map out peat hydrological areas this year. Last year, the agency mapped 12 such watersheds, with 12 more to be mapped this year.
The BRG also hopes to use the method to create a more detailed map, at a scale of 1:2,500, for use in planning physical peat restoration efforts on the ground, such as blocking the canals dug by developers to drain the peat.
“Of course we want to immediately use the winning method this year,” BRG chief Nazir Foead said at a press conference after the announcement.
With detailed maps in hand, the BRG hopes to achieve its target of restoring at least 24,000 square kilometers (9,270 square miles) of peatland by 2020. As of last year, the agency had restored less than 12 percent of that target.
The BRG also believes that the IPMT’s technology can be adopted by other countries with tropical peatlands, such as the Democratic Republic of the Congo (DRC) and the neighboring Republic of the Congo (ROC), which share what scientists recently discovered is the world’s largest contiguous span of tropical peatland, at 145,500 square kilometers — an area larger than England.
“I believe that countries like [the DRC and ROC] … could use this method as well [because] they don’t know much about their peatland yet,” Nazir said.