Vegetation of Southeast Asia Studies of Forest Types 1963-1965

may prevail In widely separated regions. Fur the more, the forest
types should be readily recognizable both on the ground and to a
certain degree from aerial observations, preferably at medium altitudes
(1,000 to 5,000 feet).
It is usually customary to assign names to Formations or Types,
based on their physiognomy or habitat, such as Evergreen forest,
Deciduous, Gallery or Riparian, or Swamp forest. Whatever terra is used,
it should be short, descriptive, applicable over wide areas, readily
understood and easily translated into other languages.
FOREST
TYPES
of
S 0 U THEAST
ASIA
Although the Conifers, so characteristic of temperate Evergreen
forests, are represented in Thailand and the other Mekong basin
countries by species of Pinus, Dacrydium, Podocarpus and Cunningharcia,
actually they constitute only a small fraction, less than 1 percent,
of the forests of that region. Broadleafed species, represented by
numerous genera, are dominant almost everwhere. So that the classification
of the forests of Southeast Aisa into Coniferous or Softwood
and Broadleafed or Hardwood species, is not considered applicable.
A more practicable method is to segregate the forests of those
countries into two broad categories: (a) Evergreen forests, which
include the Conifers; and (b) Deciduous forests.
The forests of Thailand may be assigned to about twelve Climax
Formations or Types, all or most of which also occur in North and
South Vietnam, Laos and Cambodia. These primary types may be furthered
divided into Sub-types or Sub-climax communities, according to
variations induced by such factors as micro-climate, and localized
edaphic or biotic conditions.
EVERGREEN FORESTS
(1) RAIN FOREST: (See Figs. 20, 21)
Synonyms:
Tropical Rain forest, Evergreen Rain forest,
Tropical Wet Evergreen forest, Wet forest,
Wet Evergreen forest, Tropical Evergreen
forest, Broad-leaved Evergreen forest;
Evergreen forest and the Foret dense humide
of French ecologists.
Of the several terms applied to this Type, the rather long 'Tropical
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