Forests in Thailand are divided into two main types: evergreen forest and deciduous forest. Each type is also classified into different types of forest as follows.
1.1) Tropical rainforest
It is a forest in an area with high humidity. Influenced by the monsoon wind. The average rainfall is more than 1,500 millimeters per year. The soil is constantly moist. Can grow in both plains and high mountains. They are widely distributed from the northern region down to the southern region and can be subdivided according to moisture conditions. and low elevations of the terrain are of 3 types:
1.1.1) Tropical rainforests may generally be called “rainforests” or “rainforests”.
Characteristics of the forest and outstanding trees It is a forest that occurs in areas that receive almost a lot of rain. All year round and has relatively high soil moisture. Regularly throughout the year, the forest structure is dense and consists of many different types of plants. Most of the upper trees are in the rubber family. There are large trunks ranging from 30 - 50 meters high. Palm vines, areca nuts, and rattan appear a lot. There are shrubs, herbaceous plants, and bamboo. On the trees, there are various types of orchids, as well as mosses and ferns growing everywhere. Including more vines In other forest types, the dominant trees include trees in the Yang-Takhian family, such as Yang Na, Yang Sian, Yang Pig Fat, Yung Yang. Takhian Chan Ta Maew, Takhian Thong, Takhian Root and other trees such as Krabak, Kiam, Khai Khiao, Saya, Kalo, Lum Por, Tanghan, etc.
Factors in forest formation With more than 2,000 millimeters of rainfall per year, humidity is very high.
Areas found in the southern and eastern seaboards The Chanthaburi and Trat regions may be found in other regions where there is a lot of moisture and can be divided by differences in height above sea level.
1.1.2) Dry evergreen forest
Characteristics of the forest and outstanding trees Dry evergreen forests have a similar structure. A humid rainforest has a lush canopy throughout the year. But in this forest there will be different types of plants. Deciduous, mixed, but more or less, depending on the weather conditions and soil moisture. The structure of the forest consists of 3 layers of canopy. The prominent trees of the upper canopy are 25 meters high and up, including Yang Daeng, Yang Na, Yang Pai, Takhian Hin, and Takhian Thong. Khiam Khanong, Tiger's Eye, Krabak, wild longan, bile Mafai and Krabak. Important trees that do not shed their leaves include Makha Mong, Tabak, rosewood. Deciduous species include Sompong, Po I Keng, So, Ma Mue, Yom Hin, Yom Pa, Neem Chang, Gangkha Dueat, Ta Baek Yai, Tabak Kreab, Salo Dok Khao, Som, etc., canopy. The second floor has a height of about 10 -20 meters and consists of trees such as large-leafed plantain, Krabao Klak or Klang's head, Lamduan, and Diospyros trees. The lower trees are usually not more than 5 meters tall, consisting of thorny koi, marang mo, white needles, etc. on the ground. The forest has trees of prominent trees. It grows densely, including ginger, galangal, and rattan. And the vines found orchids on the trees.
Factors in forest formation Distributed along the plains, foothills, hillsides, and valleys with an altitude of approximately 300 - 600 meters above sea level. The average rainfall is approximately 1,000-1,500 millimeters per year.
The area found is spread everywhere. Especially the regions that have a dry season between 4 - 6 months, including the central region. some parts of the north and northeast
1.1.3) Mountain rainforest
Characteristics of the forest and outstanding trees It is a rainforest that grows on high altitude areas. From 1,000 meters above sea level, the forest has a dense canopy. There is a wooden floor below. Dense like tropical evergreen forests and dry evergreen forests on low areas, but different in the composition of the plants. Prominent trees include trees in the genus, such as the genus, such as the genus, the genus, the dam, the ridge, the casing, the thorn, and the dicotyledonous plants. (Jimnosperm) and other trees such as Miang, Mueakon, Montha, Champi Luang, Hom Chang, Makham Pom Dong, Klang Suea Krong, Kayom, Jumpi Phaya Mai, Saraphi Dong, Pink Phu Phan, White Rose, and Red Rose, etc. and palms such as Kho, Tao Rai Phu Kha, wood. Bottom floor: lotus fern, turtle coconut.
Factors in forest formation There is 1,500– 2,000 millimeters of rainfall per year.
The area found is scattered along high mountain peaks in every region of the country. The southernmost point appears at Khao Luang Hill in Nakhon Si Thammarat Province. But most of them are located along mountain peaks in the northern region, such as Doi Inthanon, Doi Chiang Dao, and Doi Pui, etc. In the central and northeastern regions, some are found, such as Khao Yai, Phu Kradueng, and other mountain peaks that are more than 1,000 meters high. go
1.2) Lower montane coniferous forest
It is a forest with a group of softwood trees such as conifer or mountain pine in general. Black forests grow along the mountain ridges. with cold weather and the soil is infertile, most are at an altitude of 200–1,800 meters above sea level, with average rainfall. 1,000–1,500 meters per year, the forest condition is characterized as a sparse forest. This type of forest is scattered in patches. They are mostly found in the northern region, such as Chiang Mai, Chiang Rai, Mae Hong Son, Lampang, Tak, and Phetchabun, and some places in the northeast. in the provinces of Loei, Sisaket, Surin and Ubon Ratchathani, etc. If there are frequent fires It will be like a field forest, such as at Phu Kradueng and Thung Salaeng Luang, etc. The composition of the tree types depends on only a few types. Two-leafed pine and three-leafed pine are the dominant trees. There are other types of trees that grow together, including Three-thousand-year-old Phaya pine, Bai Pai pine, Khun Mai Sang Jing. In some areas, the soil is laterite and is a deciduous dipterocarp forest. There are vines, antimony, trees in the Kor family mixed with pine and shrubs such as Phikun, Pa Khem Pa, Ma Ha, Red Khang, Chang San, Cycad, and white rose etc.
1.3) Mangrove forest or mangrove forest (Mangrove forest)
Mangrove forests are forests that grow in muddy land near the sea. along estuaries where seawater floods and on various islands Both the Gulf of Thailand and Andaman coast From Ranong Province to Satun Province, in the Gulf of Thailand, from Samut Songkhram to Trat, from Phetchaburi to Narathiwat. Mangrove forests have characteristics of the forest structure and the composition of the plants. In particular, the prominent trees include: large-leafed mangroves and small-leafed mangroves, both of which have buttress roots or stilt roots coming out of the base of some trees, such as samae. Lamphu Prasak has aerial roots sticking out of the muddy ground, called aerial roots. Other types of trees such as Phang Ka Hua Sum, White Prong, Red Prong, and True Rangka, etc.
1.4) Peat Swamp forest
It is a forest that grows in a wetland area (wetland) that has been a freshwater pond for many years. There is an accumulation of organic layers. Organic material or soil that is more or less thick above the actual soil layer. Accumulation of plant remains and organic matter that occurs continuously in flood conditions obtained from rainwater each year. This may be in the plains on both sides of the river, along swamps and swamps, mostly in areas with an average rainfall of more than 2,000 millimeters per year. that various plants Having to live in an environment that is waterlogged and wet like this causes adaptation. and has special characteristics such as At the base of the tree there is usually a pupon. Most root systems The roots will be wide and strong. There will be a special root system or additional root system such as breathing roots to help with breathing and buttress roots to help support the trunk. Can be classified according to the environment into 2 subtypes:
1.4.1) freshwater swamp forests or swamp forests
Characteristics of the forest and outstanding trees Freshwater swamp forests are different from swamp forests in that swamp forests occur in areas that are pan-shaped basins. Where there is a permanent accumulation of plant remains or organic matter that has not decayed, mostly submerged in fresh water received from rain. Freshwater swamp forests occur along the plains on both sides of rivers and large streams in the southern and central regions. and freshwater swamp forests in the northeast, such as the Mun Chi River, called Pa Bung-Tham. Areas that are swampy with standing water are called Bung. Upland areas with few large trees are called Bung. The freshwater pond forest receives fresh water that overflows the river banks during the flood season. There is no accumulation of waste on the forest floor. Permanently organic matter Because plant remains Water is carried away with the fluctuating tides. The structure of the forest will vary. Varies in each locality depending on the terrain. river bank The amount of water in the flood season and the condition of the soil, freshwater swamp forest on the plain side in the flood season. The water level is quite high. There will be trees covering it. Grouped areas scattered and trees There is not much height. The bottom is grass and sedge. The upland area that is flooded is Occasionally in a short period of time you will find a group of medium-large trees. densely covered area Contact in large pieces Trees that are commonly found in freshwater swamp forests such as garden cone, kang krao, large Krabao, takhop nam, sak nam, chum saeng, sakae, mamuang pan, xiang pra nang ae, inthanin nam, phikunphru, now nam, chin, wah, sab nam, san nam, samphao, tiajik or kradon nam, inthanin nam. Sok Nam, Krathum, and Rakam Pa, etc.
Factors in forest formation Waterlogged or flooded areas
The areas found are the southern region (Tapi River), the central region (Chao Phraya River, Sakae Krang River, the northeastern region (Mun Chi) and are called Pa Bung Pa Tham.
1.4.2) Peat swamp forest
Characteristics of the forest and outstanding trees It is a deciduous forest. It grows in low-lying wetlands. It is in the condition of a basin with fresh water trapped all the time. Different from freshwater swamp forests Generally there is a peat forest floor. There will be a continuous and permanent accumulation of organic matter until it becomes organic soil (peat) above the actual soil layer. It has a thickness of not less than 50 centimeters. In freshwater swamp forests, there will be no permanent accumulation of organic matter layers. But there will be an accumulation of sediment or mud. The plants that grow in these flooded forests have adapted to their surroundings. It has a short taproot system. The base of the tree has bulges. It has a special root system to help support it. And helps in breathing. Important plants include Chang Hai, Ai Bao, red sandalwood, bird durian, krai, big-leaf buffalo's blood, tamarind, pikunphru, samet, chumphu pa, echoing birds, ai bao, wild sandalwood, Tanyong pa satiao, peat peat, sugarcane sheaths and various types of wa, etc.
Area found: Southern region (area of swampy areas with standing water such as Toh Daeng peat peat forest, Narathiwat, Kuan Kreng peat peat forest Nakhon Si Thammarat) Northern Region (Ang Ka Doi Inthanon, Chiang Mai Province)
1.5) Beach forest
It is a plant society that grows along the sea coast. Normally, the sea water cannot reach it. Most are sand dunes, some are gravel mixed with sand and rocks. If the area on the seashore rises and away from the shore Or if the condition is similar to an island, there will be a lot of soil mixed in. There may be open air conditions. Undergrowth of grass, shrubs, and herbaceous plants or in a grove condition. or the condition of a forest with the canopy close together The plant species that grow in this type of forest must be those that tolerate salinity. and can adapt to strong winds Drought and salt air from the sea And there are ground cover plants clinging to the sand extending in lines such as gaur, sea po, sea hemp, staghorn, elephant ear mangrove, sand trotters, sea maojik, sea barren, sea pokring, sea yee, sea candle, sea elephant trunk, ivory tusks, shrubs such as rak talay, blood ivory, khon thiso talay. Thorn Phung Tor, sea pandanus, thorn carpet, vines such as morning glory, Dong Dung Chan Din, floating grass, and nuts, etc.
2.1 Deciduous forest or mixed deciduous forest
It is a forest that consists of many types of plants. Most will drop their leaves in the dry season until only the branches remain. This is because during the dry season plants lack water. to be used in dehydration Therefore, we must adjust by dropping leaves to reduce the transpiration of water from the trees. It looks like a more or less sparse forest consisting of A mix of large, medium and small trees. In some places there are different types of bamboo growing. This type of forest in some areas has teak, salao, tabak, rakfasaenkham, samopipek, red, and padauk mixed in. The ground is usually sandy loam. There is moderate soil moisture. This type of forest is economically important. Because it consists of many valuable types of wood that can be easily accessed and harvested, the soil and environment are suitable for agriculture. As a result, this type of forest has been encroached upon and destroyed by illegal logging and land clearing for agriculture.
2.2 Deciduous forest, red forest, hump forest or goat forest
Found mostly in the northeastern region. (About 80 percent of this type of forest) in the northern and central regions. There is no forest of this type in the southern and eastern regions besides the Hiang tree group. Some are seen in Surat Thani Province. The characteristics of this type of forest are sparse forests consisting of medium and small deciduous trees growing far apart. Scattered, not very dense The forest floor has grass and dwarf bamboo such as Pek and Chod bamboo growing everywhere. The foliage is quite dense. It grows both in the plains and on the mountains with heights of 50–1,300 meters above sea level. The soil is lacking in fertility, mostly sand and laterite. In some places there are exposed rocks. And forest fires occur every year, causing trees to adapt. Therefore, trees that can survive are trees with thick bark, fire and heat resistance, and have a high ability to sprout. Fire and deciduous forests therefore They belong together. Without fire, only fire can preserve the condition of the deciduous forest. The deciduous forest will gradually The condition has changed to a different type of forest. The 5 predominant types of trees are dipterocarp, rang, hiang, antimony, and variegated.
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