about Sri lanka
Sri Lanka is a tropical island located in the Indian Ocean off the southern tip of peninsular India, between latitudes 5° 55 - 9° 51 North and longitudes 79° 41 - 81° 54 East. It is one of the “Biodiversity Hotspots” in the world and harbours numerous endemic species. The island is 65,610 Square kilometers in extent and consists of three peneplains; lowland (up to 300m above sea level), upland (300-900m above sea level), and highland (> 900m above sea level). According to the distribution of rainfall, three major climatic zones are recognized; the dry zone (with an annual rainfall <1900mm), the wet zone (annual rainfall >2500mm), and the intermediate zone (annual rainfall 1900-2500mm).
The island also contains three distinct mountain ranges; the Central hill massif, the Rakwana range towards the South-west, and the Knuckles range towards the North of the Central massif. Based on climate (temperature and rainfall), 15 floristic regions have been designated on the island. The geo-climatic diversity in the island is reflected clearly in the variety of inland natural ecosystems and habitats. Forest types range from dry monsoon forests in the dry coastal lowlands and closed-canopy rainforests in the South-western seasonal lowland wet zone quarter to tropical montane cloud forests reaching a maximum altitude of 2,524m in the central highlands.
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Archaeological evidence indicates that Sri Lanka was home to Paleolithic (Homo erectus) also known as the Old Stone Age people from around 300,000 BP and even as early as 500,000 BP. Strong evidence indicates prehistoric settlements by about 125,000 BP. Furthermore, it is known that a group of Mesolithic hunter-gatherers known as the Balangoda Man (named after the place where his remains were found) was probably the first modern inhabitants of the island who lived in caves prior to 34,000 BC. Several of these caves, namely the Fa-Hien, Batadombalena, Beli-Lena, Alawala, and Nilgala bear ample testimony to the existence of this anatomically modern man in South Asia. Later evidence shows large settlements, believed to be before 900 BC at Anuradhapura indicating the existence of an Iron Age culture. Nevertheless, the earliest known inhabitants of the island were probably the Indigenous Veddahs, hunter-gatherer people numbering around 3,000 whose descendants still live in the Uva Province of Sri Lanka.
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Sri Lanka boasts 103 river basins and, through the use of modern technologies, some of these rivers are being regulated by the use of dams and reservoirs. Most of Sri Lanka’s land mass is arid, and the rivers are important for irrigation and water supply. The Rivers of Sri Lanka originate in the central highlands. From there they descend to the plains and empty into the sea. The rivers are typically unnavigable in their higher reaches, where they flow swiftly and turbulently through highly eroded passages to the plains below. Many rivers descend over steep cliffs, forming spectacular waterfalls. In their lower courses, the rivers slowly meander through flood plains and deltas. Having the highest waterfall density in the world with a recorded 382 waterfalls spread throughout the country, Sri Lanka is the place to be to see all kinds of waterfalls. Fed by two half-yearly monsoons, rivers rush down the rocky precipices and form spectacular waterfalls. Only some of these picturesque waterfalls can be viewed with ease as the others are located inside thick forests and around tea plantations.
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Irrigation systems of ancient Sri Lanka consist of a large number of village reservoirs to gigantic reservoirs and an intricate network of water canals connecting these tanks while supplying water to farming land. There are about 30,000 reservoirs in Sri Lanka of which the majority were built from the 3rd century BC to the 12th century. This compared to the Sri Lankan dry zone land area of about 40,000 sq. kilometers (where almost all the tanks are located), is almost equivalent to one reservoir for each sq. kilometer.