BIOGEOGRAPHICAL SETTING OF MALAYSIAN FLORA
Malaysia is an integral part of the Indo-Malayan or Malesian phytogeographical zone extending from the Kra Isthmus in peninsular Thailand in the northwest, to Papua New Guinea and its adjacent islands in the southeast. In this zone, more than 40,000 species of vascular plants have been recorded. Of these, slightly more than 36,000 are flowering plants, 3,600 are ferns and fern allies, and 87 are conifers. The total number of lower plants, such as fungi, algae, liverworts and mosses, and lichens, is not yet known. In comparison to this magnificent array, Europe, with a total land area of about 9 million square kilometres, is home to only 11,500 species of vascular plants—approximately one-quarter of those found in the much smaller Malesian zone of 3 million square kilometres.
By unit area, the flora of Malaysian lowland and hill mixed dipterocarp rainforests is also much richer in species than any other type of vegetation in the world. Many species are endemic, such as the dipterocarp tree, Dipterocarpus lamellatus; the largest pitcher plant, Nepenthes rajah; one of the smallest flowering plants, the orchid Corybas comptus; and a bamboo, Yushania tesellata. This high species diversity is attributed to the prevailing moist and warm climatic conditions, and to the availability of diverse types of microhabitats resulting from past and recent geological history. The ability of indigenous and introduced species to adapt, compete and invade newly formed habitats, and the existence of different reproductive strategies among plants of different taxa growing in the same habitat, are also reasons for the high species diversity.
The rainforests of Malaysia are very complex in structure. Many trees, such as kapur (Dryobalanops aromatica) and tualang (Koompassia excelsa), attain a height of 84 metres, while a few species of orchids and aquatic plants reach a maximum size of only a few centimetres. Between these extremes is a variety of plant groups, including many herbs, shrubs and trees, and species of climbers, stranglers, epiphytes and parasitic as well as saprophytic plants. Both the complex structure and the diversity of the rainforest have a direct bearing on its ecological role in maintaining and stabilizing nutrient cycles, food chains, energy flows and heat and water balance. The elimination of these forests may have a pronounced effect on the climate and ecological balance at local, regional and global levels.
Malaysia's forests also provide useful products, such as timbers, rattans, fruits, vegetables, medicines, spices and ornamentals, and habitats for a range of wildlife. To sustain its ecological and economic functions, the conservation and wise utilization of the Malaysian rainforest and its resources are extremely important. To this end, a sizable amount of forest has been put aside as national parks, wildlife sanctuaries, and other such areas of conservation.
