Thailand's dramatic economic growth has caused numerous environmental issues. The country faces problems with air, declining wildlife populations, deforestation, soil erosion, water scarcity, and waste issues. According to a 2004 indicator, the cost of air and water pollution for the country scales up to approximately 1.6–2.6% of GDP per year. As such, Thailand's economic growth has come at great cost in damage to its people and environment.
Thailand's Twelfth National Economic and Social Development Plan (2017-2021) warns that, "At present the country's natural resources and environmental quality are deteriorating, and have become a weakness in maintaining the basis of production, services and sustainable living. A large volume of the natural resources stock has been utilized for development, resulting in their continuous degradation. The forests have been depleted, the soil has become infertile, and biodiversity has been threatened. While exhibiting a future risk of water shortages, the existing supply of water has not been able to meet the demands of the various sectors. Conflicts over the use of natural resources stem from the unfair allocation of access and exploitation. Moreover, environmental problems have risen along with economic growth and urbanization. All of these problems have affected the quality of life and have added greater economic costs."
Climate change
Deforestation
Forest cover in Thailand has been greatly reduced as people convert forested land to agriculture, or misappropriate public lands for private use, with related estimates varying. The Sueb Nakhasathien Foundation reports that 53% of Thailand was covered by forest in 1961, but that forested areas had shrunk to 31.6% in 2015. An estimate by the World Wildlife Fund concluded that between 1973 and 2009, Thailand's forests declined by 43%. During the period 2001–2012, Thailand lost one million hectares of forest, while restoring 499,000 hectares. Between 1990 and 2005, Thailand lost 9.1% of its forest cover, or around 1,445,000 hectares. , Thailand has an average annual deforestation rate of 0.72%. Wetlands have been converted to rice paddies and urban sprawl. With government measures in place to prohibit logging, deforestation rates have dropped, but the impacts of deforestation are still being felt.
Thai government numbers show an increase in the extent of Thai forests. Figures from the Center for Agricultural Information of Thailand's Ministry of Agriculture and Cooperatives show an increase in the extent of Thailand's forested area over the period 2006-2015 (from 99 million rai to 103 million rai), with decreases in every other type of land use. In 2019, the Forest Department said that forest cover has steadily increased due to its anti-encroachment measures under the regime's reclaim forest land policy. According to the department, the country's forest areas in 2018 covered 102.4 million rai, a 330,000-rai increase from the previous year. The increase, equivalent to an area the size of Phuket, increases forest coverage to 31.58% of the country's total land.
In early-2017, the government reaffirmed its 1975 commitment to increase its forest cover to 40% within 20 years. The aim was to have "conserved forests" blanket 25% of the nation and 15% blanketed by "commercial forests". To achieve this goal in 2018, Thailand would need to convert 27 million rai into forests. Thailand has three square meters of green area per capita. Singapore has 66 m2 per capita and Malaysia, 44 m2.
In November 1988, heavy rains washed away the soil of newly deforested slopes, causing massive floods. Villages and agricultural land were swamped, and almost 400 people and thousands of domestic animals were killed. The Thai government banned logging on 14 January 1989, revoking all logging concessions. Consequences included the price of timber tripling in Bangkok, in turn increasing illegal logging.
In June 2015, as a severe drought gripped northeastern Thailand, Prime Minister Prayut Chan-o-cha urged farmers to forgo a second rice crop in order to save water. He attributed the drought to massive deforestation. At least 26 million rai (4.2m ha) of forested land, especially forests in the mountainous north, had been denuded, according to the prime minister, who said that forests were needed for the generation of rainfall.
In July 2015, a Bangkok Post editorial summed up Thailand's forestry issues: "Forests have rapidly declined under state policies over the past four decades. Factors include logging, mining, anti-insurgency strategies, promotion of cash crops on the highlands, construction of big dams and promotion of the tourism industry. Corruption is also deep-rooted in forestry bureaucracy." Valuable hardwood tree species, such as Siamese Rosewood, are being extracted illegally for sale, mostly to the Chinese furniture market. These trees are so valuable that poachers are armed and are prepared fight forest rangers. Both rangers and poachers have been killed in gunfights. The rates of logging now threaten the Siamese Rosewood with extinction within 10 years, according to Al Jazeera in 2014.
Mangroves and beach erosion Deforestation creates a host of environmental problems: soil erosion, sedimentation of rivers, and loss of natural habitat. Wetlands and mangroves in coastal areas have been seriously degraded by expansion of commercial fishing, shrimp aquaculture, industry, and tourism, causing much of Thailand's biodiversity losses. Mangrove wetlands are among the leading habitats in carbon sequestration, and degradation of these habitats poses risks to global carbon accumulation. They are hypothesized to dampen the intensity of tsunami force, which would protect both human and biodiversity interests. It is estimated that Thailand in 1961 had 3,500 km2 of mangrove forests. By 2004 that number was less than 2,000 km2 according to the Thai government.
According to Thailand's deputy transport minister, some of Thailand's attractive beaches may be lost within ten years. "If we don't do anything, there will be no attractive beaches left", he said. The marine department, part of the transport ministry, manages Thailand's 3,000 km of shoreline in 23 coastal provinces. Some 670 km of shoreline exhibits severe erosion, with land being lost to the sea at a rate of more than five metres per year. To combat erosion, sections of Pattaya Beach in Chonburi Province are being topped up with more than 300,000 m3 of sand at a cost of 429 million baht. A two kilometer stretch of Chalatat Beach in Songkhla is being restored at a cost of 300 million baht.
Thailand had a 2018 Forest Landscape Integrity Index mean score of 6.00/10, ranking it 88th globally out of 172 countries.
While conservationists have advocated for creation of marine protected areas in mangrove forests, coastal communities in Thailand are concerned these protections may interfere with their economic growth. Mangroves provide these communities with profit opportunities, mainly through agriculture and tourism practices including the operation of rubber plantations, aquaculture, and fishing. The Thailand central government has enacted stricter, community-based mangrove restoration laws which shift emphasis from regulating mangrove removal to promoting mangrove conservation. This initiative provides flexibility for local government to approach mangrove conservation efforts as they see fit, which has proved successful for communities in the Phuket, Phang Nga, and Trang provinces. Communities without the financial means to enact these recent policy changes rely on private entities to fund restoration efforts. Another solution to satisfy environmental and economic concerns may be payment for ecosystem services (PES), a method of conservation that incentivizes sustainable environmental practices. PES helps support communities transitioning to sustainable practices, however a lack of funding challenges wide scale support for PES and its implementation.
Air pollution
The World Bank estimates that deaths in Thailand attributable to air pollution have risen from 31,000 in 1990 to roughly 49,000 in 2013.
Industrial growth has created high levels of air pollution in Thailand. Vehicles and factories contribute to air pollution, particularly in Bangkok, which experienced high levels of air pollution in the winter of 2019. Recent research (2019) points to agricultural burning as the root cause of PM 2.5 pollution in Thailand. PM 2.5 is a measurement of particulates in the atmosphere smaller than 2.5 microns.
The Bangkok metropolitan region, which consists of the Bangkok Metropolitan Administration (BMA) and the four surrounding provinces (Nonthaburi, Pathum Thani, Nakhon Pathom, and Samut Prakan), holds about 20% of the national population and over half of the country's factories. Due to a lack of treatment facilities, increasing volumes of hazardous substances generated by industrial activities have caused serious dumping issues. Unless treatment facilities are built and institutions starts to regulate strictly, environmental contamination caused by hazardous waste threatens to become Thailand's worst environmental problem in the future.
Thailand's Pollution Control Department (PCD) and other agencies have developed standards in order to reduce air pollution. The standards focus on shifting to lower-emissions vehicle engines and improving public transportation. In 1999, 80% of the motorcycles on the road in Bangkok had environmentally unfriendly two-stroke engines. Diesel trucks and buses also contribute many pollutants. In most areas of the country, air pollutants for vehicles are now within acceptable levels according to national standards.
Factories and power plants have been required to reduce emissions. In 2002, Bangkok and the rest of the central region contributed between 60 and 70% of the country's industrial emissions. Most power plants rely on burning fossil fuels.
Other sources of air pollution include garbage burning, open cooking, and agricultural burning practices, including deliberate forest fires.
Agricultural burning in Southeast Asia often creates haze. In 2003 Thailand ratified the ASEAN Agreement on Transboundary Haze Pollution to reduce the haze from forest fires, but issues throughout the region are still common. Wildfires are started by local farmers during the dry season in northern Thailand for a variety of purposes, with February and March as the two months when conditions are at their worst. In research conducted between 2005 and 2009 in Chiang Mai, average PM10 rates during these months were found to be well above the country's safety level of 120 μg/m3 (microgrammes per cubic metre), peaking at 383 μg/m3 on 14 March 2007. They are the main cause of the intense air pollution in the Thai highlandsMushroom Research Center and contribute to the floods in the country by completely denuding forest undergrowth. The dry forest soil leads to lower water intake for trees to extract when the rains arrive.
In February 2016, Director-General Chatchai Promlert of the Disaster Prevention and Mitigation Department, said that the haze affecting northern Thailand has reached levels that can be considered harmful to health. He said that the Pollution Control Department had reported that the levels of particulates measuring less than 10 micrometres—known as PM10—had crossed the prescribed safe threshold of 120 in four out of nine provinces where monitoring was conducted. The level of PM10 in the nine regions—Chiang Rai, Chiang Mai, Lampang, Lamphun, Mae Hong Son, Nan, Phrae, Phayao and Tak—was measured at between 68 and 160. The haze level was considered unhealthy in Chiang Mai, Lampang, Lamphun, and Phrae Provinces.