2.1 Location and Physical Characteristics

Thailand, centrally located in the Indochina Peninsula, is one of the most developed and wealthiest countries in Southeast Asia. It is bordered by Cambodia and Laos on the east, Laos and Myanmar on the north, Myanmar on the west and Malaysia and Gulf of Thailand on the south. It is bounded between 5⁰ 40’ and 20⁰ 30’ North latitudes and 90⁰ 70’ and 105⁰ 45’ East longitudes (Fig. 1). The total area of Thailand is 513,115 sq. kms.

Physiographically, the country has been divided into six regions viz. Central plain, Southeast coast, Northeast plateau, Central highlands, North and West continental highlands and Peninsular Thailand. Due to these variations, Thailand possesses tremendous natural and cultural diversity. The forest vegetation for example, ranges from pine forests on the north to lowland rain forests or tropical mangrove forests on the south.

The climate of Thailand is defined as "humid tropical" which is influenced by the seasonal monsoon and the local topography. Two distinct types of climate are recognised : tropical rain forest climate and tropical savannah climate. The tropical rain forest climate is characterised by uniformly high temperature and heavy rainfall without possessing any distinct dry season. The tropical savannah climate on the other hand is characterised by less precipitation with three distinct seasons. The rainy season extends from May to October, hot dry season from March to April and cold dry season from November to February. The average annual precipitation and temperature varies from region to region. The following table provides information on the generalised climatic data for the six physiographic regions of Thailand.
 
 
 
 

Table 1. Generalised Climatic Data for the six physiographic regions of Thailand
 

Physiographic  Region	Annual rainfall (mm)	Annual mean humidity %	Annual mean temperature (0 C)	Absolute maximum temperature (0 C)	Absolute minimum temperature (0 C)
Central plain Southeast Coast Northeast Plateau Central Highlands North and West Continental Highlands West Coast East Coast	1,220-1,592 1,312-4,456 1,089-2,163 1352 1,045-1,744 2,177-5,106 1,018-2,568	64-76 74-78 68-73 70-73 71-75 77-83 78-82	27-29 27 26-27 26-28 24-28 27 27-28	39-44 38 42-43 41-43 40-43 35.5 38-39	5-12 9 2-4 2-7 2-6 19 14-18

Source: Meteorological Department, Thailand

The total population of the country is 58.34 million (Ongsomwang, 1995) with a population density of 113.7 persons/sq. km. The following table provides information on the growth of the population and population density during last 15 years.

Table 2. Total Population, Population Density and Population Growth of Thailand
 

Year	Total Population	Male	Female	Density per sq. km.	Annual Growth Rate (%)
1980	46,961,338	23,627,727	23,333,611	92	1.84
1981	47,875,002	24,067,597	23,807,405	93	1.95
1982	48,846,927	24,549,873	24,297,054	95	2.03
1983	49,515,074	24,911,684	24,603,390	96	1.37
1984	50,583,105	25,449,044	25,134,061	99	2.16
1985	51,795,651	26,059,668	25,735,983	101	2.40
1986	52,969,204	26,642,889	26,326,315	103	2.27
1987	53,873,172	27,070,155	26,803,017	105	1.71
1988	54,960,917	27,574,256	27,386,661	107	2.02
1989	55,888,393	28,001,343	27,887,050	109	1.69
1990	56,303,273	28,181,202	28,122,071	110	0.74
1991	56,961,030	28,463,102	28,497,928	111	1.17
1992	57,788,965	29,018,092	28,770,873	113	1.43
1993	58,336,072	29,205,086	29,130,986	114	0.95
1994	59,095,419	29,552,978	29,542,441	115	1.30
1995	59,460,382	29,678,600	29,781,782	116	0.62

Source: Statistical Year Book of Thailand, 1993 and 1996

2.2 Present Land Cover

Thailand is well endowed with cultivable land which represents a significant portion of the country’s total area. Agricultural land supports rice paddy, upland crops, para rubber, oil palm and perennial crops etc. Both evergreen and deciduous forests including mangrove forests can be found in Thailand. Other land cover types found in Thailand are urban areas, waterbodies, others that includes abandoned land, marsh land, swamp, rock-outcrop, beach and pasture land.

Evergreen and deciduous forests are the two principal forest types, abundant in various parts of the country. The distribution of these forests depends on climatic, edaphic, topographic and biological factors. Evergreen forests can further be sub-divided into tropical evergreen forests, tropical rain forests, dry evergreen forests, hill evergreen forests, coniferous forests and swamp forest. Both freshwater and mangrove swamp forests can be found. Deciduous forests are sub-divided into mixed deciduous , dry deciduous and savannah forests

The following table provides information on the distribution, elevation range and dominant species of various forest types found in Thailand.

Table 3. Forest types, forest distribution, elevation range and dominant species

found in Thailand
 

Forest Types	Forest Distribution	Elevation Range (m)	Dominant Species
Evergreen Forest Tropical Evergreen Forest 1.1.1 Tropical Rain Forest Dry Evergreen Forest Hill Evergreen  Forest Coniferous 1.3 Swamp 1.3.1 Freshwater 1.3.2 Mangrove         1.4 Beach     2.0 Deciduous Forest 2.1 Mixed Deciduous         2.2 Dry Deciduous     2.3 Savannah	Along the wet belt of the country with high rainfall and no dry period, scattered all over the country. South-eastern and Peninsular regions.     Scattered all over the country along the depressions and along the valleys of low hill ranges. Scattered all over the country scattered in small pockets in the North, Northeast, East and Southwest regions scattered in the wet region of the country along depressions inland     along river estuaries and muddy coastlines on the west coast, south and south-east common along the east coast occurs on coastal dunes, rocky seashores and elevated coasts scattered all over the country         scattered all over the country     north, northeast and in the eastern region	0 - 100      ~ 500      ~ 1000  200-1600                                                     50-600          100-600	Dipterocarpus spp., Hopea spp., Shorea spp.Anisoptera spp.palms, rattans, abamboos and climbers etc. Dipterocarpus spp. Hopea ferrea, Anisoptera costata, Alstonia scholaris, Tetrameles nudiflora etc. Quercus spp., Lithocarpus spp., Castanopsis spp. Etc. Pinus spp., etc. Dyera costulata, Palaqium gutta, Scaphium spp., Hopea latifolia, Heritiera littoralis spp. Etc. Rhizophora apiculata, Rhizophora macronata, Soneratia spp., Bruguiera spp., etc. Casuarina equisetifolia etc.     Tectona grandis, Xylia kerrii, Dalbergia cultrata, Dalbergia oliveri, Albizia lebbeck, Accacia spp. Etc. Shorea robtusa, Pentacme siamensis, Dipterocarpus spp., Phyllanthus emblica etc. Careya arborea, Accacia siamensis, Accacia catechu etc.

Forest encroachment and commercial logging are two leading factors responsible for forest destruction. Conversion to shrimp ponds, salt pan and paddy field is typical problem for mangrove forest destruction. The Status of forest areas in Thailand from 1961 to 1993 has been presented below.

Table 4. The Status of Forest Areas in Thailand 1961-1993
 

Year	Forest Area		Decreasing Rate (Mil Rai / Year)	Population (Mil)
	Mil Rai	% of total Country Area
1961	171.03	53.33	3.1	30
1973	138.57	43.21	2.7	40
1976	124.01	38.67	4.9	45
1978	109.52	34.15	7.2	48
1982	97.88	30.52	2.9	50
1985	94.29	29.40	1.6	52
1988	89.88	28.03	1.5	55
1989	89.64	27.95	0.2	56
1991	85.44	26.64	2.1	57
1993	83.45	26.02	1.0	58

Source: 1) A Land Policy Study, edited by Tongroj Onchan

2) Forestry Statistics 1990, Royal Forestry Department, Thailand

3) Forestry Statistics 1994, Royal Forestry Department, Thailand