TROPICAL RAIN FORESTS GLOBAL DISTRIBUTION

14 CHAPTER I INTRODUCTION

1.1 TROPICAL RAIN FORESTS

For hundreds of years the stereotype of rainforest is lush jungle plants, colourful birds, humidity and heavy rainfall. According to the Longman and Jenik 1987, the word forest refers to three different concepts: a Timbers or plants as trees, b all plant community dominated by trees. c All community areas that are dominated by trees which functions, including biotic substrate and atmospheric environment. The world’s tropical forests circle the globe around the Equator. They are amazingly diverse and they consist of lush rain forests, dry savannas and containing complex ecosystems and millions of species of animals and plants. Tropical forests once covered some 6.2 billion ha Mastrantonio Francis 1997. In recent times, however, they have been cleared at a rapid rate to build urban areas, agriculture and to get their many valuable products. Between 1985 and 1990, 85 million ha of tropical forests were destroyed Mastrantonio Francis 1997. Forest covers 27.7 of expanse of Earth and as much as 53.4 of this forest area number is tropical forest, 21.2 is temperate forest and 25.4 is boreal forest Longman Jenik 1987. But according to Myers 1988 tropical rainforest total area in the world has been estimated as only 9 millions km 2 , and about 76-92 thousand km 2 , have been destroyed every year.

1.2 GLOBAL DISTRIBUTION

The largest remaining areas of tropical rain forests are found in Amazon Basin, Congo Basin, and Indo-Malaya Basin. Lowland rain forests are among the world’s most productive of plant communities, giant trees may tower 60m in height and support thousands of species of plants and animals. The trees in the rainforests carry profusion of parasitic or heavy climbing plants, and, in some portions, a “jungle” of dense 15 undergrowth near the ground. For lack of marked climatic seasons, growth proceeds throughout the year Mastrantonio Francis 1997. Kindly check Figure 1.1 to verify the distribution of forests around the world Figure 1.1Tropical rainforest: worldwide distribution, Source: Encyclopedia Britannica 1997.

1.3 IMPORTANCE OF TROPICAL FORESTS