National Park Office director Chaiwat Limlikhitaksorn says he is concerned about losing 265,286 rai of forest land in Thap Lan National Park to an agricultural land reform project.
He has invited the public to oppose the government's effort through an online poll organised by the Department of National Parks, Wildlife and Plant Conservation (DNP) until July 12.
Thap Lan National Park covers an area of about 1.4 million rai in four districts of Nakhon Ratchasima and one district in Prachin Buri.
The park is part of the country's Dong Phayayen-Khao Yai Forest Complex, a World Heritage site.
The Prayut Chan-o-cha's cabinet decided on March 12 last year to let the Ministry of Natural Resources and Environment revoke the protected area for Sor Por Kor land plots to solve land disputes between locals and the national park.
The new borderline is drawn based on the government's One Map project, which standardises maps used by state agencies at a scale of 1:4,000 to solve problems caused by overlapping boundaries.
"People should be concerned if the national park's borderline will be changed due to last year's cabinet's resolution. With the new borderline, the department will lose 265,286 rai to the Office of Agricultural Land Reform (OALR)," he said.
He said the land can later change hands after farmers have owned it for five years, but that was not the right way to solve the land dispute problem.
He said Thap Lan was listed as a national park in 1981, three years after OALR announced land reform proposals for the area.
At that time, the disputed land covered about 58,882 rai.
However, after OALR conducted a new survey and the One Map project in 2016, the land in dispute increased to more than 260,000 rai.
The land was located in Soeng Sang and Wang Nam Khieo districts, one of the popular resort areas in Nakhon Ratchasima province.
Mr Chaiwat said those on disputed land are not only landless farmers but also investors and resort owners who want to create wealth.
If Thap Lan National Park loses its forest reserves, it could create a wave of land demands in other areas, he said.
"There are 316,560 households on disputed land nationwide today," he said. "If the 'Thap Lan model' succeeds, the country will lose about 4.2 rai of forest land to those who have encroached."
This runs counter to the 20-year national strategy, which stipulates the country must maintain 40% of its land as natural woods, he said.
Before the new borderline takes effect, a process to gauge public opinion will be held, he said, urging people to share their opinions via the online poll, which can be accessed via the Facebook page of Thap Lan National Park (facebook.com/ThapLan.NP).
He said the survey will be available until July 12. He added that public hearings over the matter will also be held on Thursday and Friday in Nakhon Ratchasima, Prachin Buri and Sa Kaeo.
The results will then be forwarded to the national committee which is overseeing the national park for consideration, he said.