This report was prepared by

1. Country overview

2. Land resources

3. Water resources (AQUASTAT)

4. Plant nutrient resources

5. Hot spots

6. Bright spots

7. Challenges and viewpoints

8. References / Related internet links

1.   Country overview

1.1  Geography and administrative units

1.2  Socio-economic features

1.3  Climate

1. > top

1.1  Geography and administrative units

  • Geographical location

    Thailand is located in the middle of the Indochinese Peninsula, between latitudes 5o27' and 20o27'N, longitudes 97o22' and 105o37'E. (Map 1.1.1) The Kingdom's total area is 513.115 square kilometers, of which some 84 percent falls within the mainland section and 16 percent within the Peninsular South. The extreme length from north to south measures 1,620 kilometers, while at its broadest Thailand is only 780 kilometers wide from east to west. The narrowest strip at about 11o43'N latitude on the Peninsular South is 10.6 kilometers. The Isthmus of Kra is some 64 kilometers wide, situated further south at about 10oN latitude. The form is therefore anything but compact, affording Thailand excellent access to the seas with 23 of its 76 provinces touching the coastline.

    The "golden axe" shape, in fact, provides over 2,705 kilometers of shoreline, facing both the Pacific and Indian oceans, with several hundred islands. The seacoast bordering the Gulf of Thailand is 1,840 kilometers long; that bordering the Andaman Sea is 865 kilometers long. There are basic physical differences and variations in resources between these two coastlines.

    The land boundary extends for some 3,400 kilometers, on the mainland and the peninsula. Politically, the land boundaries are shared with Malaysia in the Peninsular South, Socialist Republic of the Union of Burma to the west and northwest, the Democratic People's Republic of Laos to the northeast, and the Democratic Kampuchea to the southeast. (Map 1.1.1)

  • Administrative units

    Formerly, Thailand a land of 513,115 square kilometers was socially divided into 5 regions namely: Northern, Northeastern, Central, Eastern and Southern parts. Administrative units in Thailand are: provinces (75); districts (795); subdistricts (81); tambons (7,255); and moobans (villages)(69,864). (Map 1.1.2) Major cities are: Bangkok (capital of the Kingdom), Chiang Mai in the north, Khon Kaen in northeastern, Chon Buri in the east and Songkhla in the south. Only two metropolitan areas are: Bangkok and Pataya that the governers are elected by elections the rest are from appointed by the government.

[Map 1.1.1: Outline Map]

[Map 1.1.2: Administrative Boundary Map of Thailand]

1.1 > 1.

1.2  Socio-economic features

  • Population

    Thailand has a population of about 62.3 million, the average population density is around 116.7 persons/km2 in 1996 and has increases to 121.4 persons/km2 in 2000. The average population growth is around 0.89 %. (Figure 1.2.1) and (Figure 1.2.2) illustrated population by age group in 2000 and population growth 1996-2000.

  • Economy

    Real GDP of Thailand in the last ten years (1990-1999) was 11 % from agriculture, 41.5 % from manufacturing and 47.5 % from service sector. Services became the biggest sector of real GDP which can be divided into 4 sub-sectors namely: 1) trade (wholesale and Retail ), 2) tourism, 3) transportation - communication and 4) financial services. (Figure 1.2.3)

    From an early dependence on agriculture, the Thai economy rode high on a strategic mix of manufacturing and service-based industries. In terms of foreign exchange, tourism continues to provide the biggest source of revenue with over 6,000,000 visitors during 1995 (Figure 1.2.4). Other leading earners are textile and garment manufacturing and, more traditionally, the export of rice.

    In an era where phrases such as information Technology' and Globalisation' are now cliches in their own right, Thailand has all invested heavily in technology, both as an important tool for development, and in certain areas such the manufacture of integrated circuits, in establishing its own manufacturing capability. High technology manufacturing then represents some 20% of the country's exports (Figure 1.2.4).

    Growth in the financial sector has paralleled that of industry and commerce in general with the establishment in 1990 of the Stock Exchange of Thailand and the expansion and strengthening of financial institutions. International investment, particularly in the manufacturing sector, has been substantially encouraged by the Board of Investment which grants tax concessions and other privileges to suitable applicants.

    Up to 1995, the Thai economy had been growing at a rapid pace, with growth rate ranging from 8-12% per annum. And Thailand example was often used as a model that less developed countries should try to follow. Looking back in hindsight, it could be said that there was over confidence in the economy's ability to continue to grow rapidly, and looming problems, such as massive debt creation and possible loss of competitive advantages in labor intensive manufactured products, were not taken serious enough. Other problems such as the risk in large inflows of short term capital in the past, and over investment in real estate leading to substantial over supply with implications on the quality of financial institutions' loan, make the task of managing the situation even more difficult. However, concrete improvements are needed over coming few years, as it is unlikely that the country can sustain the level of current account deficit and inflation that it had experienced over the past couple of years without adverse impact on overall confidence in the country's macro economic stability. The situation will need to be carefully monitored and effective measures will be needed from the authorities.

    (Figure 1.2.5) illustrates the employment statistics in 1998. It shows that agriculture is still a leading sector. The unemployment rate is 4.36 % in 1998 which was the first year of Asian economic turbulence, compared with the previous rates of 1.54% in 1996 and 1.51% in 1997.

    In 1997, the Thai economy came to a crashing halt ending over a decade of rapid economic growth. Thailand was the first of the Asian Tigers (South Korea, Hong Kong, Taiwan, Singapore, Malaysia, Indonesia, and the Philippines) to fully feel the aftermath of the US dollar rising above the rates of many other world currencies in 1995. Thailand's form of currency, the baht, was pegged against the dollar for exchange rate purposes; as the dollar rose in value as did the baht causing Thai exports to rise in price and become expensive. As Thai export products increased, they were no longer competitive and consumers begin to look for cheaper goods; however, in order to keep the Thai economy favorable for foreign investment the value of the baht could not be diminished. Thai businessmen were sure the value of the dollar would decrease soon enough but instead their economy crashed on July 2nd,1997 devaluing the baht to more than 30 percent against the dollar. (World Book 1999)

    The effects of the baht falling were felt immediately in the Philippines, where lending rates rose only to be followed by rifts in Malaysia. On July 14th, the Philippines asked for IMF support in protecting Mexico from what was soon to become a crisis. That same day Malaysia abandoned its protection of the ringitt, it's own currency. The crisis comes full circle on July 24th when currencies throughout Asia plummet to the ground. Thailand is the first of the "Asian Tigers" to ask for assistance from the IMF. They receive their bailout on August 11th, 1997 of $16-US billion ($1.5 US billion came from the World Bank) in terms that the Thai Government raise taxes, cut spending, and keep inflation below 9 percent.

    Until 1997 when the Asian Economic Crisis hit, Thailand had an average GDP growth rate of 8.9 in 1994; this drastically fell in 1997 to -0.04. The scare finally occurred in 1997, when international banks (who were giving out these loans to local Thai banks) and money traders came to the view Thailand would have to devalue its currency and abandon the baht peg with the dollar in order to stay competitive among export communities. The government resisted, knowing large companies that had borrowed vast sums would be crippled. Traders begun to sell local currency in exchange for dollars it was like a run on the bank during the American Stock Market Crash in 1929.

    The World Bank was one of the establishments loaning money to Thailand at its time of economic growth. Both the IMF and World Bank praised Asia as its "miracle." The Asia Tigers followed the IMF strategy for economic growth and development by increasing exports and decreasing trade barriers, which lasted with success for three decades. This is best shown in the following graph of Thailand's economic growth rates. However, if Asia chose to follow these guidelines at one time and still plummeted to the ground economically, one should question if by following these practices again to overcome debt the same cycle will not again occur.

    During the economic boom, large companies took out vast loans; these loans, however, were not in baht, Thai's local currency, they were in US dollars. At the time, US interest rates were lower and due to the baht being pegged against the dollar Thai firms were making the most economical decisions. This proved not to be the case when the dollar rose in 1995 sending waves through Thailand. But many businessmen refused to see the warning signs and continued to take out loans. Business was carried out on the pretense of buy now and pay later when the currency rate fluctuated back into place.

    The export sector played a vital role in Thailand's economic recovery in 2000, with an annual growth rate of 19.5% representing the first two-digit growth rate in 4 years. In addition, exports as percentage of GDP also rose from 48.0% in 1999 to 56.8% in 2000. (Figure 1.2.7 and 1.2.9) while Figure 1.2.8 illustrates the GDP of Thailand from 1999-2002 as compare to 1988 price.

    Most of Thailand's major exports which grew considerably in value in 2000 were capital intensive industrial goods such as computers & parts, integrated circuits (IC), vehicles & parts, plastic pellets, radios, TV & parts, iron & steel products, chemical products. Labor intensive industrial goods with strong growth were garments, while agricultural goods which increased substantially in export value were rubber, chilled & frozen shrimps, etc. IC, which was Thailand's second-ranking export earner, registered a high growth rate in all of Thailand's major export markets, namely, USA, ASEAN, EU and Japan. Meanwhile, export of computers & parts, which was Thailand's most important export item, grew substantially in the Japanese market but declined in the other 3 markets. Export of vehicles & parts to ASEAN rose considerably but increased only slightly in the EU and Japanese markets, while the value of export to USA declined. Thailand's major export market for garments was USA. In 2000 Thai garment export to USA rose sharply, increased moderately in ASEAN and declined in the Japanese market. Following a slowdown in 1999, export of electrical appliances, especially radios, TV & parts, increased in all major export markets, particularly more than doubling in EU. For iron and steel products, plastic pellets and chemical products, Thailand continued to enlarge its market share significantly in all major export markets, except for plastic pellets exports to EU which declined continuously from 1999.

    More than 70% of Thai exports relied on four major export markets, namely, USA, ASEAN, EU and Japan. In 2000, the growth of Thai exports in all major export markets was the crucial factor that constituted a high growth in total exports of 19.5%. Moreover, export diversification to five emerging markets, including the Middle East, Africa, South Asia, South America, and Eastern Europe, became more successful.

    Especially in South Asia and South America, the value of exports to each market grew by more than 40% in 2000.

  • The role of agriculture in the country's economy

    Agriculture in Thailand in 1999 declined to 10 % of GDP. The total production of major agriculture sectors (fishery, rubber and rice) for the period of 1994-1998 shows an increasing trend.

    Currently, the agricultural sector is focused on export. In 1998, fishery production consisted of 12.5% of export earning, compared with that of rice 8.7% and rubber 5.5%. Other important commodities are cassava, sugar and livestock products. The staple food crop is rice, with the farm value of 4100 million US$ in 1997.

    Trend of major agriculture production is illustrated in (Figure 1.2.12).

  • Food security

    The Office of Agricultural Economics of the Ministry of Agriculture and Cooperatives Thailand is appointed as National Focal Point for establishing national food security information system as recommended by FAO abiding by Rome Declaration and World Food Summit Plan of Action. At the regional level, FAO, in collaboration with ASEAN Secretarial and ASEAN Food Security Reserve Board (AFSRB) has followed up the working progress and requested the ASEAN member countries to temporarily adopt the food security information system framework as presented in the AFSRB meeting. The AFSRB has currently collected information of 4 major commodities including rice, maize, sugar and soy bean.

  • Major food crops and cash crops and trends in production

    Present status of food production

    The major food products from agricultural sector are rice, upland food crops, vegetables, fruits, livestock products and fishery products while the minor products are tea and coffee. Rice production in 1994 increased by 18 % as compared to 1993 and in 1997 increased by 33 % as compared to 1996. Upland food crops production in 1994 also increased 36 % as compared to 1993 and in 1997 increased by 11 % as compared to 1996 while vegetables and fruits slightly increased as from 1993-1997. Fishery products (shrimps and canned seafood) and livestock products in 1997 increased 30% and 62 % as compared to 1993 respectively which indicate a new trend in food production. (Table 1.2.2) shows farm value in 1993-1997 in million Us $.


    The 1998/99 Paddy Measures

    1. To shore up the paddy price with the following projects:

    1.1 Paddy Mortgage Program of BAAC : The principle government program used to support farm prices is the Paddy Mortgage Program administered by the Bank of Agriculture and Agricultural Cooperatives (BAAC). Rice farmers can mortgage their paddy for a 3 percent inter loan valued at 90 percent of government target prices. Different target prices are set for paddy based on the percentage of broken rice (Table 1.2.3)

    1.2 Project on the Cooperative's Integrated Loans for Production and Marketing Services : The provincial cooperative federations provide loans to buy paddy from the cooperative members. The primary paddy price is set at least equal to the target price. After the paddy is milled and sold to the local people, the net revenue will be proportionally divided to payback to members in relation to the amount of paddy sold to cooperatives.

    2. Improvement of rice production efficiency

    2.1 Procurement of cheap fertilizer for the farmers: Ministry of Agriculture and Cooperatives (MOAC) has set up a fertilizer procurement program and sells the procured fertilizers to the farmers at prices lower than the market. In 1998, 700,000 metric tons of fertilizers were provided to paddy farmers at 10 percent lower than market price and the government absorbed the transport cost from Bangkok to the Production areas. The farmers can buy fertilizers on credit terms free of interest if payment is made within 6 months. Payment within 6 - 9 months costs 9 percent interest, and within 12 months, 12.5 percent per year.

    2.2 Seed distribution program: It is designed to select farmers institutions to produce and sell cheaply the high-yielding seeds; and government will compensate part of the seed production cost in an attempt to make it widespread to encourage farming efficiency and farmers' income at the same time.

    Estimated major commodities' supply and utilization are explained in Table 1.2.4.

    2.3 Provision of the low-interest credit from BAAC to the individual farmers and farmers institutions for the production investment purpose.

[Figure 1.2.1: Population by Age Groups, 2000]

[Figure 1.2.2: Population Growth 1996 - 2000]

[Figure 1.2.3: Employment by Sectors]

[Figure 1.2.4: National Income Accounts GDP 1994 - 1998]

[Figure 1.2.5: Export products of Thailand in 1998]

[Figure 1.2.6: Tourist Status of Thailand]

[Figure 1.2.7: Thailand's export as percentage of GDP from 1996-2000]

[Figure 1.2.8: GDP of Thailand from 1999-2002 as compare to 1988 price]

[Figure 1.2.9:Thailand's total export 1996-2000]

[Figure 1.2.10:High growth major export of Thailand in 2000]

[Figure 1.2.11:Thailand's major export markets in 2000]

[Figure 1.2.12:Trend of major agriculture production]

[Table 1.2.1: GDP of Thailand from 1999-2002 as compare to 1988 price]

[Table 1.2.2: Trend in food production]

[Table 1.2.3: Target prices for paddy rice]

[Table 1.2.4: Estimated Major Commodities' Supply and Utilization]

1.2 > 1.

1.3  Climate

  • Climate description

    The climate of Thailand is tropical, and much influenced by the country's position. The Indochinese Peninsula is part of the Asian land mass that extrudes between two great ocean bodies-the South China Sea of the Pacific Ocean and the Aadaman Sea of the Indian Ocean. While the Peninsular South is bounded by seas on both its east and west shores, the mainland part of the country is also in comparatively close proximity to two large bodies of water-the South China Sea to the east, and the Andaman Sea plus the Bay of Bengal to the west. The monsoons, resulting from the Seasonal differences in temperatures between the land mass and the oceanic body, alternately blow southwesterly and northwesterly over Thailand. The South and Southeast Asia monsoons are the most powerful of all monsoons, dominating Thailand's climate. The surrounding water, as well as the physiographic terrain, again contribute much to modifying the monsoon effects on various localities of the country.

  • Climatic data

    The seasons

    As a tropical country, only the wet and dry seasons are succinctly differentiated. This is especially true in the Peninsular South and the lower mainland sections. For the upper mainland sections, however, a greater distinction between temperature differences during the dry season justifies a broad separation of "summer" and "winter". Such a seasonal change is the result of monsoon wind directions, interacting with the location and terrain.

    - The southwest monsoon carries moisture from the Indian Ocean, normally from May to mid-October; but for the upper mainland sections, it is effective from mid-May to September. Its initial strength correlates with that of the high pressure center over the Indian Ocean in the Southern hemisphere.

    - The northeast monsoon brings in dry and cold air from China, and is normally active from mid-October to mid-February, sometimes extending into March. It causes a cool, dry season for the upper mainland section. The eastern shore of the lower South, however, receives this northeast monsoon after it has travelled across the South China Sea, picking up moisture and bringing more rain. Therefore, its wet season is in effect extended, with even higher precipitation, until January or later.

    - The switch-over or inter-monsoon period, from mid-February to mid-May, coincides with the sun's position moving northward across the equator. Increased heat absorption by the land mass and much reduced rain produces a very hot climate, especially for the upper mainland sections. The wind can be very variable, with occasional storms. The lower section often receives southerly winds coming up from the Gulf, sometimes referred to as a southeast monsoon, making it generally cooler than the upper mainland section.


    A general observation is that the further away from the sea in Thailand, the less the precipitation. Interacting with the monsoons, location and terrain exert a considerable influence. Storms also provide additional precipitation inputs.

    - Thailand's location creates two general effects. First, the upper mainland section is exposed to a shorter period of the southeast monsoon, by approximately one month. The total for the North is therefore no greater than for the Northeast. Second, the lower east coast of the South has an extended wet season, because of the north east monsoon that picks up moisture over the South China Sea well into January or February. The same northeast monsoon passing over the rest of the country will not have picked up that moisture and is therefore dry and cold.

    - The terrain can add to or subtract from what would be considered the "normal" share of precipitation. There are at least four areas where pronounced orographic effects are evident: the west coast of the middle South; the southeast corner of the Southeast coast, the leeward area of the west mountains; and the leeward area of the Phetchabun and Dong Phrayayen ranges. The first two areas receive very heavy precipitation (near 4,000 millimeters), being on the windward side of high mountains with, perhaps, still very good forest cover. The latter two areas do not receive their fair share (around 1,000 millimeters or less), since much of the moisture has been trapped on the windward side of the mountains, and they are the areas whose soil is relatively fertile for a number of crops.

    - There are two types of storms affecting the annual precipitation of certain areas.

    i) The tropical or depression storm, downgraded from the typhoon of the Pacific Ocean while crossing the Annam Cordillera, can bring heavy rain, mostly to the upper Northeast and North during August to September. A full-scale typhoon could hit the exposed Peninsular South, but, fortunately, their occurrence close to the equator is infrequent. A rare depression storm may also originate in the Gulf or the sea nearby, and producing heavy rain, especially along the coastal areas.

    ii) The cyclone from the Bay of Bengal could cross over Burma into Thailand. When it does, its force has typically been much weakened.It could be expected in May, and again form October to December.


    A Two characteristic trends in temperature variation fit two broad areas of Thailand.

    - The upper mainland section covers the North, Northeast, Southeast, West and Central, with the exception of areas adjacent to the seashore. The range of mean maximum temperatures will be 33o-38oC. The highest-ever temperature in April between 1951 and 1999 was 44.5o5C. Higher maximum temperatures normally occur in April due to greater solar absorption, less wind and less cloud cover. Cloud cover and rain seem to exert greater influence in depressing the maximum temperature. The Northeast benefits least from extensive cloud cover, and night radiation is strong. The daily range of temperatures will be 8o-12oC, but a wide range of as much as 20o during "the cold months" may be observed. Lower minimum temperatures occur in December and January, due to the northeast monsoon and heat radiation losses, with the mean minimum at 10 oC. The upper North and upper Northeast normally will be exposed first to the very cold and dry northeast monsoon, and experience very low minimum temperatures. The coldest January temperature recorded between 1951 and 1999 was 0.1 oC.

    - The lower section covers the Peninsular South and mainland shoreline region. Temperatures are more uniform year-round, with a daily range of about 10 oC. The mean maximum temperatures in December and in April differ by about 3 oC in Bangkok, and by only 2o C in the lower South. The proximity to the sea helps alleviate the temperature extremes. The extreme maximum temperature registered between 1951 and 1999 was 40 oC, while the minimum temperature was 8.9 oC.

    Atmospheric pressure

    Any effect of the change in atmospheric pressure due to altitude is not readily observable in Thailand; only two effects may be cited. First, in the mountainous area above 1,350 meters, the Monsoon Forest will be replaced by Evergreen Mountain Forest, indicative of lower temperatures. Second, on a few higher elevation mountain slopes or intermontane basins the average temperature will be lower than at lower elevations.

    The atmospheric pressure changes that considerably influence Thailand's climate are the high or low pressure centers built up over the distant oceans or the land mass, and the atmospheric disturbances that breed cyclones over the oceans.

    - The high pressure center over the Indian Ocean, in the Southern hemisphere, affects the southwest monsoon strength, influencing the amount of precipitation.

    - The high pressure center over China, in the Northern hemisphere, influences the northeast monsoon strength that, in turn, is related to dry weather and low temperatures over most of Thailand, and to additional precipitation over the lower east coast in the South.

    - The high pressure center built up over the South China Sea influences the "Southeast" monsoon, or southerly wind, in the Gulf of Thailand during the "switch-over" period from the northeast to southwest monsoons. It is moist and warm, so it raises some temperatures and brings occasional rain.

    - The tropical cyclones that regularly form over the Pacific or the Indian Oceans at low latitudes, may pass through or pass by Thailand as a tropical depression, tropical storm or typhoon, from 3 to 4 times annually. Each can bring in precipitation over a wide area along its path, the amount varying from moderate to very heavy.

    Tropical cyclones originating in the Indian Ocean can be expected in May, and again during October to December; those from the Pacific Ocean, may be expected during August and September over the upper section, and during October to December over the lower section of the country. (Map 1.3.1) below illustrates annual average climate of Thailand.

[Map 1.3.1: Mean annual rainfall, relative humidity, temperature and evapotranspiration in Thailand in last 30 years Map]


1.3 > 1.

2.   Land resources

2.1  Physiography

2.2  Soils

2.3  Agroecological systems

2.4  Wetlands, mangroves and inland valley bottoms

2.5  Inundation Land Types

2.6  Natural hazards

2.7  Land cover/Land use

2.8  Land use change

2.9  Land Productivity

2.10  Environmental Impact of land uses

2. > top

2.1  Physiography

    The location of Thailand straddles the area between two mountain systems-the Central Cordillera and the Cordillera of Annam-two of the four systems that fan out southwards from the Yunnan Knot, beginning at about 28oN latitude. The Central Cordillera gives Thailand its mountains in the North and West, and continues on into the Peninsular South and Malaysia. The Cordillera of Annam provides the mountains east of Thailand, on the boundary with Laos and beyond. The wide depression between these two mountain systems contains the alluvial plains of Chao Phraya and the Khorat Plain, known more familiarly as the Northeast Plateau or Khorat Plateau.

    Structural geology describes this depression on which Thailand is located as part of the Yunnan-Malayan geosyncline (also designated as the Burma-Malaya geosyncline), which has undergone a long series of structural changes. The evidence suggests that such changes began in the Precambrian period (570 million years ago), again in the mid-Carboniferous period (220 million years ago), at the end of the Triassic period (190 million years ago), and toward the end of the Plicocene epoch (1.5 million years ago), for the latest round. Minor changes continue. Each change is believed to bring about the orogeny and/or epeirogeny, and metamorphism responsible for the rich mineral resources deposition in some areas.

    Plate tectonic theory places Thailand on an inner perimeter of the Southeast Asia Plate, which is being compressed from opposite directions by the Indian Plate to its west and the Philippine Plate to its east. Continuing plate movements exert immense pressure and generate intense heat, capable of transfiguring our tranquil land-scape-and the resources underneath. But on the scale of a single human lifetime, it will be Man himself that transforms these given resources for the better or for worse.

         Physiographic regions of Thailand are prequently indicated and distribution of certain landforms and soils.

         These landforms (Map 2.1.1) comprise the relief features that are accumulated by either wave, wind or stream action. They range in age from recent to old Quaternary.

    1. Beach and Dune Formations:

    2. Active and Farmer Tidal Flats of recent marine and brackish water deposits:

    3. Former Tidal Flats of older brackish water deposits:

    4. Flood Plains of recent river alluvium:

    5. Low Alluvial Terraces of semi-recent and old alluvium:

    6. High Alluvial Terraces and fans of old alluvium and colluvium:

    7. Depressions with Peat and Muck:

    8. Dissected Erosion Surfaces and Structural Plateaux occurring over rocks:

    9. Lava Plateaux and Volcano Remnants:

    10. Limestone Outcrops:

    11. Hills and Mountains:

[Map 2.1.1: Main Landforms of Thailand Map]

2.1 > 2.

2.2  Soils

    Soil survey and classification techniques were first introduced into Thailand in 1935. Initially, soil survey activity was scattered among different departments of the Ministry of Agriculture. Later, soil survey and classification were transferred to the of Land Development Department (LDD), following its establishment in 1963.

    The first general soil map of Thailand was prepared and published in 1953, at a scale of 1:2,500,000, by R.L. Pendleton, an American advisor to the Department of Agriculture and Fisheries. The soil units, commonly called "soil series", shown on the map were limited. These soil units were not as sophisticated as today's "soil series", as defined in the Soil Survey Manual (USDA, 1951). They were broad generalizations, usually on the level of the great soil groups, or of the association of two or more such groups.

    The second general soil map of Thailand,was prepared and published, at a scale of 1:1,2500,000, by Moormann, and Rojanasoonthon (1968). The map units were based on the soil classification outlined by Dudal and Moorman, (1963). Twenty-three basic map units were distinguished.

    Since 1970,LDD has adopted the "Soil Taxonomy of the National Cooperative Soil Survey" developed by the U.S. Department of Agriculture. All soil series established in the country were placed into soil families using this classification system. A revision of the general soil map by Moormann and Rojanasoonthon (1968) was carried out by the Soil Survey and Classification Division and was published, at a scale of 1:1,000,000, in 1979. The soil units shown on the map were great groups and associations of the great groups. A total of 36 the great groups were recognized in Thailand (Changprai, 1983).

    LDD published a number of soil maps at different scales, such as 1:500,000 for the regional soil maps, 1:100,000 for the provincial soil maps and 1:10,000-20,000 for specific projects. At present, it has completed detailed reconnaissance soil surveys of the whole country. Provincial soil maps at a scale of 1:100,000 were published.

    Currently about 300 soil series have been identified in Thailand. Most probably, well developed soils are found and they are differentiated on the basis of USDA Soil Taxonomy into 9 orders namely: Histosols (0.14%), Spodosols (0.12 %), Oxisols (0.03%), Vertisols (0.81 %), Ultisols (42.13 %), Mollisols (1.17 %), Alfisols (9.16 %), Inceptisols (9.4 %) , Entisols, slope complexes, water bodies and others (33.75%).

    Histosols mostly consist of Fibrists. Spodosols are mostly Humods whereas Oxisols are Orthox. Vertisols are mostly Uderts and Usterts while Ultisols are Aquults, Ustults, Humults and Udults. The Mollisols consists of Aquolls ans Ustolls. Alfisols are Aqualfs, Ustalfs and Udualfs. Inceptisols are mainly Aquepts and Tropepts while Entisols are Aquents, Psamments, Fluvents and Orthents. (Map 2.2.1)

[Map 2.2.1: General Soil Map of Thailand]

2.2 > 2.

2.3  Agroecological systems

  • Agro-ecological zones (AEZ) in Thaialnd was defined on the basis of climate in relation to soil moisture availability for crops (Panichapong and Hemsrichart , 1982). In this system the agro-ecological zones were delimited according to 2 sets of criteria: (1) variation in moisture availability as required by main crops, (2) differences in soil/landform and climate. Four major agro-ecological zones were identified according to the system see (Map 2.3.1)

    Agro-ecological zones

    I. Low potential agricultural areas

    Non agricultural, organic soil areas with water logging
    Non agricultural, mangrove forest areas
    : Non agricultural, forest and watershed areas

    II. Paddy areas

    Suited areas for late varieties and growing season starts in May
    Suited areas for late varieties and growing season should be started in May with possible dry spell between June to August
    : Suited areas for late varieties and growing season should be started in June
    Suited areas for medium varieties and growing season be able to start in May but possible dry spell between June to August
    Suited areas for medium varieties and growing season should be started in July
    : Suited areas for medium varieties and growing season should be started in June but possible dry spell for one month (July)
    Suited areas for medium varieties and growing season should be started in September
    Suited areas for early varieties and growing season should be started in July
    : Suited areas for early varieties and growing season should be started in August

    III. Upland crops areas

    Areas with long rainy period (>5 months) suited for most annual crops, biennial crops and some fruit trees,growing season should be started in May
    Areas with long rainy period (>5 months) suited for most annual crops, biennial crops and some fruit trees,growing season should be started in June
    : Areas with discontinuous medium rainy period (3-4 months), suited for most annual crops and some biennial crops, growing season should be started in May but possible dry spell for one month (June or July)
    Areas with discontinuous medium rainy period(3-4months), suited for most annual crops and some biennial crops, growing season should be started in May but possible dry spell for 2-3 months (between June to August)
    : Areas with discontinuous medium rainy period (3-4months), suited for most annual crops and some biennial crops, growing season should be started in June, but possible dry spell for one month (July)
    Areas with discontinuous medium rainy period (3-4 months), suited for most annual crops and some biennial crops, growing season should be started in July
    Areas with short rainy period (<3 months) suited for tolerant short season varieties and growing season should be able to start in May with possible dry spell for 2-3 months (between June-August)
    Areas with short rainy period (<3 months) suited for tolerant short season varieties and growing season should be started in July
    Areas with short rainy period (<3 months) suited for tolerant short season varieties and growing season should be started in September

    IV. Tree crops areas

    Suited areas for tree crops, but excessive long rainy period (>8 months), and growing season should be able to start in April
    Suited areas for tree corps, but excessive long rainy period (>8 months), and growing season should be started in May
    : Suited areas for tree crops with long rainy period (5-7 months), and growing season should be started in May
    Suited areas for tree crops with long rainy period (5-7 months), but possible dry spell 3 months (between June to August), growing season should be started in May
    : Suited areas for tree crops with long rainy period (5-7 months), but possible dry spell 2 months (between July and August), growing season should be started in June
    Suited areas for tree crops with medium rainy period (<5 months), but possible dry spell 2 months (between June - July ) growing season should be started in May

  • Land capability classes (definition of LCC, % cover)
  • Land suitability for major crop types (definition of land suitability, land suitability maps) (See Annex 3 of the Guideline and Report Profile).

[Map 2.3.1: Agro-ecological zones of Thailand]

2.3 > 2.

2.4  Wetlands, mangroves and inland valley bottoms


     Wetlands  Wetlands in Thailand are found to be our ways of living. We have gained a lot from Wetlands for free particularly for public benefits. Up to now, most Wetlands have been destroyed and the rest are extremely in critical situation by:

- Increasing of population, which leads to highly requirement of Wetland for social and economical development.

    • Inefficient use of Wetland such as the water ventilation from agricultural area, use of sea water for cultural fishery, hydrology change by expansion of town , industrialization and tourism.
    • Wetland management: lack of knowledge, understanding and no law to protect wetland ecology.

    Northern Region

    In the northern part, 0.6% of the area consists of water which includes 17 provinces and area of 169,000 Sq. Kms. There are 8 International important level water resources and 57 National important level water resources. 3 wetlands are needed to be protected, 4 to be retored and 2 to be studied for ecological controlled.

    Central and Eastern Region

    There are 10 water resources in central and the eastern regions which include 26 provinces, 129,723.25 Sq. Kms. There are 6 international important level Wetlands that are Bungboraphet, Kwae Yai river system, Lower central basin, Gulf of Thailand, Krung swamp forest in Chantaburi and Wetlands around Kao Samroiyod national park. There are 47 national important level Wetlands that are Wetlands around 18 national parks (5 waterfalls, 1 beach). Wetlands around 7 national animal reservation areas (1 River and 1 Swamp). Wetlands around 8 forbidden area for animal hunting (1 Water reservoir, 1 Swamp, 3 Pastures) 8 rivers, 1 mudflat, 1 beach, 1 bay, 2 pastures and 1 swamp. 2 Wetlands are needed to be protected, 2 to be retored and 2 to be studied for ecological controlled i.e. birds species.

    Southern Region  

    It was divided into West coast and East coast. There are many old rivers on the East coast therefore more Wetlands can be found than in the West coast. In the southern part, there are at least 5,478 Wetlands which include the area of 28,465,882 Sq.Km. that is 5.548% of the area in Thailand. Most Wetlands can be found in Nakhon Sri Thammarat province. 29 Wetlands are considered to be important for an international level, 41 Wetlands for national level and 4,088 Wetlands for local level. They are divided into Coastal System and Water Resource System. 2 Wetlands are needed to be protected, 1 to be restored and 3 to be studied for biodiversification.

    North Eastern Region

    North Estern or what is called the land of plateau begins from Nakhorn Ratchasima Province. 12 Wetlands are considered to be in national important level. 2 wetlands are needed to be protected, 1 to be restored and 2 to be studies for bird migration population.


    In Thailand mangroves occur on the sheltered muddy shores and low-lying boggy ground of rivers and streams estuaries along the bank of the gulf of Thailand and in the west and east coast of peninsula. The total area of mangrove forests in Thailand,estimated using LANDSAT satellite imagery from 1979 to 1996 had been reduced for several purposes i.e. aqua-culture, agriculture, mining etc.(Table 2.4.1)

    Inland Valley bottoms

    In Thailand, we include Inland Valley bottoms in Flood Plains of recent river alluvium (Map 2.3.1)


[Table 2.4.1:Existing mangrove forest area during 1979-1996]

2.4 > 2.

2.5  Inundation Land Types

     Not available

2.5 > 2.

2.6  Natural hazards

     Natural disasters that frequently occur in Thailand include floods, droughts, tropical storms and forest fires. Whereas earthquakes and landslides occur occasionally. Generally, the sudden onset natural disasters cause the most damage to lives and properties. The rural area is the most vulnerable to disasters because of underdeveloped infrastructure. Moreover, the rural people that are mostly poor agriculturists have no ability to invest resources for reducing their vulnerability to disasters. Major destructive natural disasters are:

     Flooding  Flooding occurs during monsoon season in June-September, bring the most damage of property and claimed lives. During 1975-1990, the damage of over million US $1,216. In 1983, flood in the whole southern region had suffered 14 provinces. The damage of estimated million US $360. Over 400 lives were claimed, approximately 11,422 families or 72,814 individuals were homeless, 17,063 houses were demolished, about 1,499,892 livestock died and lost, and around 265,991 hectares of agricultural area were affected. Flooding in September 2000 brought about the damage of 57,360 hectares of agricultural area which included 53,020 hectares of paddy rice, 3,700 hectares of upland crops and 450 hectares of para rubber and fruit trees and it claimed approximately 40 lives.

     Overflowing of the Chao Praya river usually occurs in rainy se ason. The most prolonged flood in Bangkok occurred in 1995 for 2 months with the damage over million US $ 400.

     Droughts  Drought annually occurs in dry season during March-April, and they become worse and worse. It is because of water demand from agriculture and industries due to population pressure and economic development. Deforestation in association with soil characteristics and dry climate are mojor problems for drought in Thailand. In 1998 it was reinforced by the El Nino phenomenon. As a consequence, droughts affected the whole country at differential levels. The drought-stricken people suffer water shortage, especially water for drinking, cropping and livestock farming. In 1997 droughts occurred in 63 provinces, affecting 24,804 villages, 3,011,601 families or 14,394,322 individuals, and about 414,313 hectares of agricultural area.

     Tropical storms  Tropical storms associated with floods occur in Thailand during monsoon months of June-November at annual average of 4. The whole country is vulnerable to tropical storms, but the peninsular southern region is the most vulnerable area. Of all tropical storms, the typhoon Gay occurring in 1989 is the most destructive. The typhoon Gay moved inland and crossed the southern region in Chumporn province, causing 602 deaths and property damage at the estimated cost of US $ 480 million.

     Earthquake  A few earthquakes occur in Thailand and all of them are moderate magnitude. In April 1983 an earthquake registering 5.9 Richer scale occurred about 200 km. north of Bangkok. In November 1988 a severe earthquake registering 7.3 on the Richer scale occurred in the southern China. Although the epicenter was over 1,000 km. from Bangkok, it rocked high-rise buildings in the city. This is due to Bangkok stands on deep soft alluvial soil which amplified incoming seismic waves.

     Landslides   Landslides often occur in Thailand as a consequence of heavy rainfall. The most destructive one, triggered by a continuously heavy rainfall, occurred in Nakorn Sri Thammarat province in the southern part of Thailand in 1983. A great deal of land was eroded and conveyed by a huge water flow from the top of the high mountain and then slide down to low-lying land, burying the Phipoun the town located at the foot of the mountain. It caused hundreds of deaths and destroyed large amount of property. Agricultural areas were covered with thick sediment and debris washed. Map 2.5.1 illustrates preliminary risk of landslide in GIS environment by compiling types of rocks, degree of slopes, present land use, soil qualities and annual long term mean rainfall (30 years) (LDD, 2002). See map 2.5.1

     Forest fires  Forest fires in Thailand are generally by people who encroach the forest areas and burn for cropping. In 1998 the problems are aggravated by the severely dry climate as a consequence of El Nino phenomenon. Many forest lands in the country of about 129,600 acres were beyond control and caused invaluable losses of forest lands and wildlife.

     Management  Disaster management system, by law, in Thailand followed the Civil Defence Act, 1979. The National Civil Defence Committee (NCDC) is government agency that is responsible for strategic duty for disaster management who formulate civil defence measures and policies . The NCDC is composed of 17 representatives from multi-ministries concerned and functional agencies, Director-General of The Department of Local Administration being the secretary of he committee by position.

     Functional agencies for civil defence are of three categories :

          1. National level  The national civil defence center is under responsible of the Ministry of Interior.

          2. Regional level  Four regional civil defence centers have been established to support manpower, equipment and tools as well as to provide technical assistance and training to local agencies under direction of the regional civil defence directors.

          3. Local level  There are five hierarchies of local level civil defence centers namely: provincial civil defence centers (75 ) , district civil defence centers (796), Bangkok civil defence centers and Pataya civil defence centers. The centers are established to deal with all kinds of disasters that occur in the provinces, districts, Bangkok and Pataya.

Weblink :

[map 2.5.1:Risk of land slide of Thailand]

2.6 > 2.

2.7  Land cover/Land use

    There is no clear boundary between land use and land cover in Thailand. Both terms are used synonymously eventhough they should be different in reality. The newest 1: 1,000,000 land use map was produced by Land Development Department in 1998 (Map 2.7.1). The units are Paddy field 13.78%, field crops 7.72 %, perrenial 20.49 %, orchard 4.18 %, horticulture 2.41 %, swidden cultivation 3.28 %, pasture and farm house 2.67 %, aquaculture land 2.97 %, evergreen forest 13.04 %, deciduous forest 11.41 %, forest plantation 3.05 %, rangeland 2.63 %, wetland 2.91 %, mind & pit 1.78 %, urban and built-up area 1.67 %, water body 4.47 % and others 1.55 % of the land area.

[Map 2.7.1: Land use map of Thailand]

2.7 > 2.

2.8  Land use change

    Land use changes have taken place from 1986 to 1998 through population pressure and industrialization: urban areas have been increased from 2,351.97 km2 in 1986, compared to 2,575.97 km2 in 1990 and 8,569.02 km2 in 1998 while forest areas have been decreased from 185,518.2 km2 in 1986, compared to 176,478.3 km2 in 1990 and 141,106.6 km2 in 1998. Changing in agricultural lands are not clearly observed.Table below illustrated land use changes in Thailand from 1986 to 1998.

[Table 2.8.1: Land use changes from 1986 - 1998 in Thailand]

2.8 > 2.

2.9  Land Productivity

    Office of Agricultural Economic (2000) had reported average production and farm value of economic crops, fisheries and livestock in Thailand from 1990 to 1999 and it was illustrated in (Table 2.9.1).

    Productivity trends

    Total Production of Agriculture of major kinds (fishery, rubber and rice) for the period of 1990-1999 shows an increasing trend. Major agriculture production in Thailand as from 1994-1998 is illustrated in (Figure 2.9.1). Currently, the agricultural sector is focused on export. Being fishery producer which was 12.5 % of export earner instead of rice that earned only 8.7 % and rubber earned 5.5 % in 1998. Other important commodities are cassava, sugar cane and livestock products.

    (Figure 2.9.2 )illustrates that from 1990 to 1999 only Cassava and sugarcane show increasing trend in productivity while pineapple shows decreasing and the rest still maintain their productivity in the same level.

[Table 2.9.1: Average production Value of economic crops and fisheries in Thailand (1990-1999)]

[Figure 2.9.1: Food production in Thailand 1990-1999]

[Figure 2.9.2: Productivity Trend of Major Crops 1990-1999]

2.9 > 2.

2.10  Environmental Impact of land uses

    No data available

2.10 > 2.

3.   Water Resources (AQUASTAT)

3.1  Hydrography

3.2  Irrigation and drainage

3. > top

3.1  Hydrography

  • Water resources

    Water resources are vital assets in the development of Thailand. Water is essential for human consumption, sanitation, the production of food and fiber, as well as far the production of many industrial goods. But rainfed agriculture alone cannot provide sufficient products for the growing population and development of the country; therefore, irrigation is assuming an increasingly important role in the agricultural sector.

    The most striking characteristic of the water resource is its uneven and inequitable spatial and temporal distribution. Some areas have too little water, others have too much, suffering from floods which can cause substantial loss of life and damage to property. One of the main objectives of water resources development is to even out this inequity.

    An inventory of Thailand's water resources, including the amount and availability of surface water and groundwater, and discusses the status of water resources development in Thailand.

    Surface water

    The total volume of water from the rainfall in Thailand is estimated at 800,000 million m.3 of which 600,000 million m.3 is lost and the remaining 200,000 million m.3 is left as water resouces to be developed.

    The southern region receives the highest rainfall while the northern and central regions receive the lowest. The distribution of rainfall for each region is shown in Table 3.1. After subtracting losses, such as evaporation and infiltration, the average total surface runoff is about 171,206 million cubic meters (MCM).

    With the exception of the South, approximately 85 percent of the rain falls during the rainy season, i.e., from May to October. During this period, the northeastern, northern and central regions are under the influence of the southwest monsoon. In general, September is the month with the highest rainfall. In the southern region, the influence of the northeast monsoon is more important because it causes high intensity rainfall from October to January. Over 50 percent of the annual rainfall may occur in this period. Between May and September the southwest monsoon has only a weak influence on the southern region, particularly on the eastern side of the peninsula.

    The most important and the largest river basin in Thailand is the Chao Phraya Basin. It originates in the mountain ranges in the North and covers nearly all the areas in the northern and central regions. The major tributaries are the Ping, Wang, Yom and Nan rivers. Their confluence occurs at Nakhon Sawan some 200 kilometers north of Bangkok, forming tire Chao Phraya. The Pa Sak joins the Chao Phraya River about 55 kilometers north of Bangkok. The basin has a drainage area of 178,000 square kilometers. The average annual runoff at the river mouth is 30,300 million cubic meters, or 170 millimeters in terms of depth. (The volume of water is sometimes expressed as depth of water over the basil, area it covers.) The majority of agricultural products are produced in this basin.

    The second important river basin is the Maeklong Basin. The two main tributaries, the Khwae Yai and the Khwae Noi, originate in the mountain range in the West, near the Burmese border, and join together to form the Maeklong River some 80 kilometers from the Gulf of Thailand. The drainage area is 33,000 square kilometers. The average annual runoff is 13,400 million cubic meters, or 406 millimeters of depth. This basin has the highest potential in terms of water resources development, since it has much more water than would ever be needed by the land resources in the basin.

    In the Northeast, the major river basin is the Mum Basin. There are two major rivers in the basin, the Nam Chi and Nam Mon. Both rivers originate in the mountain range separating the Central and Northeast. The Nam Chi joins the Nam Man at Ubon Batchathani, flowing eastward into the Mekong River. The total drainage area is 119,573 square kilometers. The average annual runoff is 28,575 million cubic meters, or the equivalent of 238 millimeters of depth.

    In the other regions, the major river basins are the Bang Pakong Basin in the East, the Mekong and the Salween basins in the North, and the Tapi and Pattani basins in the South. Table 3.3 shows the typical flows of some of the major rivers in the country. Recently, there has been an attempt to standardize the classification and delineation of the river basins into major basins and sub-basins. This is being carried out by the Project Planning and Investigation Department of the Electricity Generating.

    Ground water

    Groundwater resources exist throughout the country. However, the quantity and quality of groundwater vary according to local hydrogeological conditions. Usually, large and high-yielding aquifers occur in alluvium and terrace deposits. To a lesser extent, groundwater also exists within crack formations in limestone, sandstone and some types of shale.

3.2 Irrigation and drainage

    The government has set its policy to develop 50 % of the remaining rainwater, at present, only 40,000 million m.3 or 20 % has been developed by several government agencies. Therefore, there's still 100,000 m.3 water resources to be further developed for the country's usage. The Royal Irrigation Department has been entrusted with the duty to provide the water such as to store and conserve ,to regulate, to distribute, to release or allocate water for agriculture, energy, domestic consumption, industry and also including prevention of damage causing by water, and inland navigation within irrigation area. Web link

3.1 > 3.

4.   Plant nutrient resources

4.1  Plant nutrient use and balance

4.2  Fertilizer Production and Cost

4. > top

4.1  Plant nutrient use and balance

    Naturally, not only soil parent materials produce low plant nutrients but also because of high leaching by rain erosion in tropical circumstances. Most of the soils in Thailand therefore have rather low fertility.

    Soils supporting undisturbed tropical forests are characterized by low soil bulk density and high macro-porosity, partly due to the relatively high activity of the soil fauna. Once the forest cover is removed, however, the soil characteristics begin to change Their bulk density increases in the wake of deforestation and cultivation, as do a number of their other physical and chemical properties. Norman (1984) compared the physical properties of new and old development areas and showed a gradual process of change. The total infiltration capacity of soils in the older development areas had fallen by 62 percent, when compared with the original forest values. The soil chemistry had also changed. The organic carbon content of tire soils in tire older areas had dropped by 18 percent, while their calcium, magnesium and potassium tended to be lower, too. (IFPRI, 1996).

    Kanchanakool (2000) had studied levels of soil fertility at 0-25 and 25-50 centimeters depth in Thailand and it was concluded that: low fertility soils in the north eastern part of Thailand are from sandstone origin and composed of kaolinite, the low activity clay. Most of the low fertility soils occur in the southern part of Thailand , a region of high intensity and long period precipitation that induce fast weathering process and leaching of parent materials (Clay mineral are found to be kaolinte, gibbsite and illite ). Soils in the cold hilly northern part vary as their bed rocks and clay minerals: higher level fertility soils are found in some parts of the region. Higher level fertility soils are also found in the central plain, especially near the east coast where most of the soils are alluvial (fresh water deposit, brackish water deposit and marine deposit). (Table 4.1.1 and Table 4.1.2)

    Land Development Department had mapped Soil Fertility based on General Soil Map of Thailand to overview the soil fertility status. (Map 4.1.1)

    Application of chemical fertilizer in Thailand was recorded by Office of Agricultural Economics (1998) and it shows trend 'to be increased from 1986-1995 as illustrates in (Table 4.1.3) and (Figure 4.1.1). Consumption of fertilizer for paddy in 1986-1995 is illustrated in (Table 4.1.4).

[Figure 4.1.1: Chemical Fertilizer used in Thailand (1986-1995) ]

[Table 4.1.1: Soil Fertility level of top soil (0-25 cm.) and sub- soil (25-50 cm) in Thailand.

[Table 4.1.2: Fertility Level from Soil Analysis by LDD and USDA standard]

[Table 4.1.3: Chemical fertilizer used in Thailand (1986-1995)]

[Table 4.1.4: Consumption of fertilizer for paddy 1986-1995]

[Map 4.1.1: Soil Fertility Map of Thailand]

4.1 > 4.

4.2 Fertilizer Production and Cost

    Most of chemical fertilizers used in Thailand are imported. OAE reported that in 2000 that Thailand imported 97,524 metric tons of Ammonum sulphate, 67,525 metric ton of Urea, 97,158 metric ton of Potassium chloride , 225,254 metric ton of 16-20-0 (N-P2O5-K2O), 32,870 metric ton of 16-16-8 (N-P2O5-K2O), 199,785 metric ton of 15-15-15 (N-P2O5-K2O) and 37,532 metric ton of 13-13-21 (N-P2O5-K2O) respectively (Figure 4.2.1).

[Figure 4.2.1: Chemical Fertilizer Imported in 2000 ]

4.2> 4.

5.   Hot spots

5.0 Overview: constraints to sustainable agriculture

5.1 Land-related constraints

5.2 Water-related constraints

5.3 Plant Nutrition-related constraints

5. > top

5.0 Overview

    Salinization is affecting irrigated lands in moderately populated areas while nutrient mining and erosion are degrading sandy soils in northern Thailand and remote upland areas in the regions. Water erosion is the major process, especially where lands have steep slope and rainfall is high. Acid and acid sulphate soils cover some parts of central plain and east coast while organic soils occurs mostly in southern part. Deforestation and improper agricultural practices are major causes of degradation in Thailand.

5.0 > 5.

5.1 Land -related constraints to sustainable agriculture

 Special problem soils

    The expansion of cultivated land is likely to be limited due to the fact that land suitable for agriculture is almost completely utilized. Existing cultivable and abandoned lands will need to be developed to meet the future land requirements. There are about 31,000,000 hectares classified as special problem soils (LDD, 2001) (Figure 5.1.1) (Map 5.1.1)They are organic soils,salt affected soils (saline soils), deep sandy textured soils, coarse loamy textured soils, acid sulfate soils, shallow soils, and slope complex soils. Some of these problem soils have already been used, including salt affected soils, acid sulfate soils and shallow soils, but their productivity is very low.

    With regard to research work on these special problem soils, only salt affected soils and acid sulfate soils have been intensively covered to date. In order to develop these areas for better utilization, the research program on each type of soil should be accelerated.

    Salt affected soils may be found in certain southern coastal areas,but these tend to be caused by seawater flooding rather than by irrigation.

    The problem of salt affected soils is worst in the Northeast, where agricultural land have been affected in varying degrees . Of these, some 350 square kilometers are "severely" affected, with salt crust coverage of 50 percent or more .

    About two-thirds of the salt affected soils can still produce crop yield of salt tolerant species, like rice, at a depressed level-about half the normal average.

    Apart from the linkage between irrigation, poor drainage and salinization, there are possibly other factors. Dammed up reservoirs raise the water table downstream where deeper saline layers exist, and flush up the salt into the surface soils. Salt production, a widespread economic activity of the area, could have aggravated the problem through its considerable wastewater discharge. Deforestation of the watershed is suspected of being linked to the leaching rate of salt from upland deposits.Whatever are the cause(s) of salinization for any specific area, there is real need for a very careful consideration of any irrigation proposal with regard to the land suitability and to adequate drainage investment. Otherwise the salt burden will be cumulative from thepresent generation to the next.

Land Degradation and Water Erosion

    There is evidence both of degradation and erosion of Thai soils. The degradation of soils can be caused by physical, chemical,biological, socioeconomic and institutional factors. In isolation or in combination, directly or indirectly, such factors alter the soil's potential for sustained or increased agricultural production.

- Soil Erosion

    Soil erosion in Thailand , in fact, is one of the most pressing natural resource problems and is influenced most probabbly by water . A theoretical study by Srikhajon, et al. (1980), indicated that about 171,200 square kilometers nationwide suffer from a medium or high degree of soil erosion, particularly upland areas where slopes are greater than 5 percent.

    Soil erosion has been increasing from 18 million ha in the year 1981 to 22 million ha in the year 1991 (ASOCON, 1998).

    Land Development Department had mapped soil erosion of Thailand in 1999, based on General Soil Map , Land Use/Land Cover Map, Geological Map and Univesal Soil Loss Equation (USLE). It was concluded that in the lowland and/or less than 35% slope: 66 % of the whole area are low eroded (12.5-32 ton/ha/yr of sediment) , 3 % are moderately eroded (32-95 ton/ha/yr) , 0.3 % are severe eroded ( 95-125 ton/ha/yr) and 0.8 % are very severe eroded (>125 ton/ha/yr). In high land and/or more than 35% slope: 21.3 % are low eroded, 4. 5 % are moderately eroded, 0.8 % are severe and 3.3 % are very severe eroded. (LDD,2000) (Map 5.1.2)

- Land Degradation

    Moncharoen, P. et. al.(1999) (Table 5.1.1)(Map 5.1.3)had estimated of vulnerability to desertification empirically by applying general soil map of Thailand that was combined with climatic and land use data to evaluate important land-related constraints for agriculture. The initial estimates suggest that about 75 % of the country is vulnerable. As agriculture is largely in the hands of the rural poor' these lands are subject increasingly to land degradation. The sloping land, which form about 30% of the country, are particularly vulnerable as they are increasingly being deforested and subject to shifting cultivation.

Improper use of Land Resources

    It has been found that a agricultural land has been misused i.e. cultivation of paddy and growing of upland crops on unsuitable soils, encroachment and destruction of forests on steep slopes, especially those that exceed 35 percent.

    It was also found that the total such an nationwide covers 6319 square kilometers, of which 3033 square kilometers are in the North which most of the encroachment is for cultivating upland crops without any soil and water conservation practices, thus creating severe erosion problems. The RFD (1984) reported that about 15,040 square kilometers of watershed area has been encroached.

Environmental Issues

    Agrochemical pollution has increased in periurban areas around Bangkok .

    Devegetation of mangrovehd been observed from the period of 1961 to 1996 and was concluded that more than 200,000 hectares was reduced. (Table 5.1.2)

    Devegetation of mangroves and associated problems i.e for aquaculture, mining, salt pans and others with subsidense and drainage are reducing the productivity of peat and acid sulfate soils in coastal areas.

[Figure 5.1.1: Extent of problem soils in Thailand]

[Map 5.1.1: Soil Potential for Agriculture (Thailand)]

[Map 5.1.2: Soil Erosion Map of Thailand]

[Map 5.1.3: Vulnerability to Desertification Map of Thailand ]

[Table 5.1.1: Area subject to desertification in Thailand ]

[Table 5.1.2: Reduction of mangrove forest during 1961-1996 ]

5.1> 5.

5.2 Water related constraints to sustainable agriculture

    Conflict over water resources is expected in the country in areas of high population density, with particular concerns about pollution and irregular provision. Coastal areas and deltas may deteriorate due to sedimentation loads and pollution (IFPRI, 1996). The effects of siltation from soil erosion on dams and from sedimentation along water courses result in a sediment load at the mouth of the Chao Phraya River of about 104 tons per square kilometer. This represents 11 million tons, or about 8.5 million cubic meters of sediment .

5.2> 5.

5.3 Plant Nutrition-related constraints

    see plant nutrient resources

5.3> 5.

6.   Bright spots

6.0  Overview: society's response to ameliorate the situation

6.1  Land-related response indicators

6.2  Water-related response indicators

6.3  Plant Nutrition-related response indicators

6.4  Other response indicators

6. > top

6.0  Overview: society's response to ameliorate the situation

    The royal speech of His Majesty King Bhumibol Adulyadej giving to Thai people in his birthday one year.

    "What others may say does not matter, whether they say that Thailand is old - fashioned or that we are out - dated. Anyhow, we have enough to live on and to live for, and this should be the wish and determination of all of us to see self - sufficiency in this country. It is not that we will attain supreme prosperity, but we will have a sustainable and peaceful country. If we keep this sustainability, we already can be considered the top in comparison with other countries beset as they are by crises and decline due to greed and rivalry for power, economic and industrial progress and in matters of ideology. So, for me, it will prove to be a birthday present of lasting value and benefit if each of you, with your ideas and power of persuasion, enjoin on others who also have the same intentions, the determination to preserve the community so that we are able to enjoy this reasonable way of life - and I stress the reasonable, sustainable, and peaceful conditions - defending ourselves against anyone who may want to rob us of our innate qualities" suggests Thai people to sustain their land and live by sufficiency economy.

    Most of the bright spots existing in Thailand have been originated by him through government sectors concern and let the projects under Golden Jubilee Network be the prototypes for all land and water resources development. See

6.0 > 6.

6.1  Land-related response indicators

    6.1.1 His Majesty The King and Land Resources Development
    • Chaipatana Foundation
        The activities of the Foundation are:

        - The polluted water development project
        - Kaem Ling (Monkey cheeks) water detention project to solve flood problem in Bangkok and its environment
        - Laem Pakbia environmental study and development project
        - The New Theory
        - Vetiver grass
        - Rama IX Golden Jubilee temple


    • The Royal Project
        A project in northern Thailand for natural resources conservation and high landagricultural development.


    6.1.2 Land Development Act, B.E. 2526

    A law on Land Development was enacted by His Majesty King Bhumibol Adulyadej, by and with the advice and consent of the National Assembly in 1983.
                1. The Act is called " Land Development Act, B.E. 2526 "
                2. This Act have come into forced as from March 1984.
                3. Director General of Land Development Department is one of the members and its secretary of " Board of Land Development "
                4. Land Development Department's duties are land survey, soil analysis to determine its qualities and suitability classification and development for special purposes.
                5. Whoever shall be against act without permission, will be sentenced to a certain term of imprisonment or a fine of certain amount of money.
    The reason from the enactment of this act is that it is deemed appropriate to transfer the power on the development of land under the Land Code with respect to the parts concerned with the survey, classification and preparation of land suitability classification for agriculture, land use planning and soil conservation to the " Board of Land Development " and Land Development Department. Any misused of land i.e. sea water inland shrimp farming will be justified by Land Development Department. (LDD, 1984)

    6.1.3 Natural Resources and Biodiversity Institute (NAREBI)

    Through NAREBI the Ministry of Agriculture and cooperatives (MOAC)is seeking to develop innovative approaches to addressing crucial emerging issues related to environmental protection and sustainable development in Thailand and the ASEAN region. Operating through NAREBI, the Ministry will mobilize the highest quality human resources within each of the Ministry 's line agencies to tackle difficult environmental unit, no matter how well-endowed, can hope to deal with all the serious environmental issues that many developing nations confront on the threshold of the 21st century. NAREBI seeks to be the bridge that will facilitated and public / private / non-governmental dialogue on the key environmental issues that affect the lives of the peoples of Thailand and Southeast Asia. With agriculture as the principle occupation of most peoples of the region, the need for sustainable management systems for natural resources and environmental protection is crucial. NAREBI will coordinate among its line agencies and with other Thai Government ministries , as well as with non-government , community-based organizations, and the private sector, to ensure the effective implementation of resources and environmental management policies. Through the organization of forums for public participation and exchange, NAREBI will foster mechanisms for dialogue among key stakeholders in the environment and natural resources sectors.

      A - Soil Resources and Land Use
           Policy 1 - Protect the soil resource from degradation and loss, and rehabilitate soil quality.
           Policy 2 - Increase effective land use practices that are relevant to soil capacity.
      B - Agricultural Land Use
           Policy 1 - Conserve and protect areas that are suitable for agriculture; at least 35% of the country's total area, with 25% designated for farming, and 10 % for pasture.
           Policy 2 - Promote and support suitable agricultural land use practices.
      C - Land Use in Unique Ecosystems and Geological Areas     
           Policy 1 - Conserve the natural balance of areas containing unique ecosystems and of geological areas.
           Policy 2 - Utilize areas containing unique ecosystems and geology resources, while retaining the natural balance.

    6.1.4 Sustainable Agriculture Development

    Ministry of Agriculture and Cooperatives' (MOAC) policy on Sustainable Agriculture in accordance with the objective for restructuring sustainable agriculture in the 8th National Plan (1997 - 2001), at least 20% of agricultural land should be used for sustainable agriculture. This will build opportunities for farmers to have higher income by providing alternatives: integrated agriculture, ecological agriculture. NAREBI was assigned by MOAC to research and create a strategy for sustainable agriculture development including the training of local officers to follow the 8th Plan. The Sustainable Agriculture strategy includes the adjustment away from mono cropping as leads to a problem with market pricing . MOAC approach to Sustainable Agriculture focus on the big picture to emphasize the link between market prices and production to decrease the risk of small farmers by supporting sustainable agriculture activities and conserving natural resources.


    6.1.5 Success story in land use

    Salit Mungfangklang , a rainfed rice farmer in Nakorn Ratch Sima Province, north eastern Thailand, who had suffered from long draught period in 1994 joined The New Theory Project  (Figure ) in 1996. He began his new life by dividing his own land of 19 rai (1 hectare is 6.25 rai) into 5 parts: paddy (8 rai), tree crops (3.5 rai), cash crops (2 rai), farm pond with fish (4.5 rai), home and homestead garden with poultry (1 rai).  (Figure )From 1999, he has his own irrigation system through out the year for his continuous cropping activities. At present he can get at least 45,000 baht (1 US$ = 45 baht) benefit excluding fish and tree crops in one year. He have tried to sustain his land by reducing chemical substances application by applying organic farming system.

[Figure New Theory land management demonstration farm in southern part of Thailand.]

[Figure Salit Mungfangklang, at his fish pond.]

6.1 > 6.

6.2  Water-related response indicators

    His Majesty The King has devoted himself to water resource development in order to help farmers have sufficient water for cultivation. His efforts have contributed to greater productivity were so outstanding that Food and Agriculture Organization of the United Nations presented him with the AGRICOLA Medal, being the first king in the world who promote water conservation to increase and saveguard food production. Royal Irrigation Department under Chaipattana Foundation has its responsibility to provide and conserving water for cultivation.


6.2 > 6.

6.3  Plant Nutrition-related response indicators

    6.3.1 Organic crop production

    Standards for Organic Crop Production in Thailand were established in 2000, as guidelines for organic crop production in compliance with international standards. The organic crop production standards were initiated and prepared by three organizations, namely: Thailand institute for Scientific and Technological Research, Department of Export Promotion, Ministry of Commerce, and Ministry of Agriculture and Cooperatives.

    Organic agriculture is a production system with primary concern to the environment, maintaining the balance between nature and bio-diversity, through a system on the management of agro-ecosystem in harmony with nature and avoidance on the use of synthetic chemicals that would cause adverse effect to the environment, including the exploration of traditional or local knowledge.

    The demand trend for organic agricultural products both at the local and international market has continued to increase a rate at 20 percent every year, as attributed to the recognition by the producers and consumers to sanitation, food safety, and environmental protection.

    Every stage of the land management should use organic and natural substances. These substances should be free from the contamination of prohibited materials as specified. In case there is a need to apply chemicals which nature is uncertain whether prohibited or not, a reference should therefore be made to the list of the substances that are permitted to be use and the limitations of each substances prior to each application. (DOA, 2000)

    6.3.1 Royal Theory on Reactivation of acid sulfate soils (Klang - Din)

    See http://

    6.3.2 Land Development Department Services Land Development Technique

    See Land Development Department have had its services in plant nutrient related :
            - Soil Consultant
            - Detereorated Soils Improvement services

    6.3.3 The Solution to Saline Soil In Thailand
    See 'and

6.3 > 6.

6.4  Other response indicators

6.4 > 6.

7.   Challenges and viewpoints

Agriculture policy of the Royal Thai Government delivered to the National Assembly by H.E. Prime Minister Thaksin Shinawatra on Monday, 26 February 2001

    Part 1: Revival and Strengthening of Farmers

       (1) Reform the debt structure and maturity profile of the agricultural sector to correspond with the crop production cycle. Expedite the resolution of farmers' debt. Implement a debt moratorium and suspension of interest payments for a period of 3 years for small-scale farmers.
       (2) Promote the practice of mixed agriculture, alternative agriculture and organic agriculture as well as support the learning process for farmers.
       (3) Support farmers to have adequate land for earning their livelihood by implementing a coordinated and comprehensive land utilization policy and by optimizing the use of idle land. The management of water resources at every level must also be improved efficiently in a manner that is suited to the production system of each crop and the conditions of the terrain. Emphasis must be placed on the full participation of the people in the restoration, conservation and development of land that is upriver as well as in river basins, reservoirs, irrigation canals, water quality, and piped irrigation. The use of surface water and underground water must also be efficient and systematic, especially in projects involving the development of large water sources.

    Part 2: Development of Domestic Markets and Strengthening Rural Communities

       (1) Develop production in the rural sector and strengthen community economies by linking the processing of agricultural produce with the "One Village, One Product" Project. A one-million-baht Village and Community Fund will be established in each village to serve as a revolving loan facility for the long-term local investments and income creation in rural areas at community levels.
       (2) Develop the marketing system for modern agricultural produce. Provide support for the construction of barns and crop drying grounds for farmer groups in rural areas. Promote the establishment of an information technology network for agriculture news and improve access to marketing information concerning agricultural goods so that farmers may undertake production planning in an efficient manner.
       (3) Promote and strengthen cooperatives, community businesses, agricultural institutions, and community organizations, enabling them to participate in making and proposing agricultural policy and measures as well as in agricultural research and development.
       (4) Increase production efficiency by promoting research and utilizing local knowledge as well as modern technological know-how.
       (5) Promote and support agriculture and agro-industry appropriate to the particular conditions of the terrain and climate as well as in accordance with the demands of the market and the capacity of each community.

    Part 3: Increasing the Competitiveness of the Agricultural Sector in the World Market

       (1) Support the creation of new value added by processing agricultural produce. Develop the quality, standards, forms, and packaging of agricultural and agro-industrial goods.
       (2) Develop Thailand as a centre for the production of organic agricultural products. Promote the registration of patents involving agricultural production in every area as preparation for future liberalization in trade of agricultural products.
       (3) Improve quality controls, standards and safety of agricultural products, both imports and exports. Support the development of biotechnology to improve productivity, quality and standard that are internationally recognized and market tested.
       (4) Promote coastal fishing, aqua-culture and marine farming as well as fishing beyond territorial waters based on bilateral cooperation with neighbouring countries, developing a strong national fishing fleet, supporting the cold storage industry, and promoting the processing of fishery goods. Conservation and protection of natural marine resources and the ecology of the seas is a primary policy.

    The government's urgent policies concerning land and water resources are;

       (1) Immediately grant a grace period for both interest and principle payments for 3 years for individual small farmers to relieve their debt burden as part of a comprehensive reform of the traditional farm economy to be more viable and self sustaining in the long term.
       (2) Establishment of the Village and Urban Revolving Fund, funded with one million baht each as a loan facility available for individuals and households of each community to borrow for local investment and supplementary vocations. Concurrently, the Government will promote a "One Village One Product" project to enable each community to develop and market its own local product or products based on traditional indigenous expertise and local know-how. The Government is further prepared to provide additional assistance in terms of appropriate modern technology and new management techniques to market such local products from the village to domestic and international outlets through a national or international retail network or through the internet.
       (3) Establish a People's Bank to ensure better and improved access to banking facilities and resources for low income citizens to enhance their capacity to increasing their income from self employment and thus reduce their dependence unorganized and punitive money market sources.
       (4) Establish the Bank for Small-and Medium-sized Enterprise in order to promote existing and increasing the number of entrepreneurs in a systematic manner with a view to expanding the national productivity base, increasing additional employment opportunity and creating income, promoting exports, and serving as the mainstay for future national economic growth and stability.


    The government's urgent policies will be under financial support of Bank of Agriculture and Agricultural Cooperatives (BAAC).


    Sufficiency economy

    The Ninth National Economic and Social Development Plan (2002-2006) adopts the philosophy of sufficiency economy bestowed by His Majesty the KingO to his subjects as the guiding principle of national development and management. The philosophy of sufficiency economy, based on adherence to the middle path, is advocated to (a) overcome the current economic crisis that was brought about by unexpected change under conditions of rapid globalization, and (b) achieve sustainable development (NESDB,2002). The philosophy can be summarized as follows:

    Philosophy of Sufficiency Economy

    "Sufficiency economy" is a philosophy that stresses the middle path as the overriding principle for appropriate conduct and way of life of the entire populace. It applies to conduct and way of life at individual, family, and community levels. At the national level, the philosophy is consistent with a balanced development strategy that would reduce the vulnerability of the nation to shocks and excesses that may arise as a result of globalization. "Sufficiency" means moderation and due consideration in all modes of conduct, and incorporates the need for sufficient protection from internal and external shocks. To achieve this, the prudent application of knowledge is essential. In particular, great care is needed in the application of theories and technical know-how and in planning and implementation. At the same time, it is essential to strengthen the moral fibre of the nation so that everyone, particularly public officials, academics, business people, and financiers adhere first and foremost to the principles of honesty and integrity. A balanced approach combining patience, perseverance, diligence, wisdom, and prudence is indispensable to cope appropriately with critical challenges arising from extensive and rapid socio-economic, environmental, and cultural change occurring as a result of globalization.

7. > top

8.   References and related internet links

8.1  References

8.2  Related internet link

8. > top

8.1  References

  • Aksornkoae, Mangroves: Ecology and Management, Kasetsart University, Bangkok, Thailand.277p. 1999.

    ASOCON, The Tenth ASOCON Consultative Board Meeting, Xi'an, China, September 14-18, 1998

    Changprai,C. Soil of Thailand. Proceeding of the Forth International Forum of Soil Taxonomy and Agrotaxonomy Transfer, Land Development Department, Bangkok, Thailand. P. 29-50. 1983.

    Department of Agriculture (DOA), Standard for Organic Crop Production in Thailand. Ministry of Agriculture and Cooperatives. 20p. 2000.

    Department of Agricultural Extension, Mixed Farming Follow New Theory , Ministry of Agriculture and Cooperatives.87 p. 1999 (in Thai).

    Dudal, R. and Moorman, F.R. "Major Soils of Southeast Asia: Their Characteristics, Distribution and Agricultural Potential." Journal of Tropical Geography. Vol. 18 p. 54-80. 1964.

    IFPRI, Land Degradation in the Developing World: Implications for Food, Agriculture, and the Environment to 2020, International Food Policy Research Institute, Washington, D.C. . U.S.A. 36 p. 1996.

    Kanchanakool, N. Soil Fertility Level in Thailand . Soil Analysis Division, Land Development Department, Bangkok, Thailand. 49 p. 2000 (in Thai).

    Land Development Department (LDD), Land Development Act. B.E. 2526, Ministry of Agriculture and Cooperatives. 8 p. 1984.

    Land Development Department, Soil Erosion in Thailand . Bangkok, Thailand.39p. 2000 (in Thai).

    Land Development Regional office 12, New Theory in Land Development Region 12 (in Thai), Land Development Department (leaflet), Bangkok, Thailand. 1998.

    Office of Agricultural Economics, Agricultural Statistics of Thailand, Crop Year 1996/97, Ministry of Agriculture and Cooperatives, Bangkok, Thailand, 1998 .

    Office of Agricultural Economics, Agricultural Statistics of Thailand, Crop Year 1997/98, Ministry of Agriculture and Cooperatives, Bangkok, Thailand, 1999.

    Panichapong, S. and Hemsrichart, P. Agro- climatological Zone of Thailand. Land Development Department, Bangkok, Thailand. 62 p. 1982.

    Moncharoen, P., T. Vearasilp, K. Hoontrakul and H.Eswaran., Desertification in Thailand. Paper Presented in The 10 ISCO Conference, 23-28 May 1999, Purdue University, Lafayette, Indiana, U.S.A. 1999.

    Moorman, F.R. and Rojanasoonthorn, S. Soils of Thailand. SSR. No. 72. Land Development Department, Bangkok, Thailand. 1968.

    Norman, B.W., Report on the Comparison of New and Old Development Areas. Thai - Australian - World Bank Land Development Project, Chiang Mai, Thailand. 1984.

    Srikhajon, M. and S. Somrang, Soil Erosion in Thailand. Land Development Department, Bangkok, Thailand. 1980.

    The Mekong River Commission Secretariat and LDD, Proceeding of National Wetland Classification Workshop in Thailand. October 17-18, 2000. Sofitel Hotel, Khon Kaen, Thailand. 2000.

    RFD, Forestry Statistic of Thailand 1984. Planning Division, Royal Forest Department, Bangkok, Thailand.1984.

    USDA, Soil Survey Mannual. Agricultural Handbook No. 18, Warshington D.C., U.S.A. 1951.

    8.1 > 8.

8.2 Related internet link
8.2> 8.

about acknowledgments disclaimer copyright
last updated: 3 December, 2002