Kanneliya-Dediyagala-Nakiyadeniya or KDN is a forest complex in southern Sri Lanka. The forest complex designated as a biosphere reserve in 2004 by UNESCO. The KDN complex is the last large remaining rainforest in Sri Lanka other than Sinharaja. This forest area has been identified as one of the floristically richest areas in South Asia. The forest complex is situated 35 km northwest of city ofGalle. The rain forest is a major catchment area for two of the most important rivers in southern Sri Lanka, the Gin and Nilwala Rivers. This biosphere reserve harbors many plants and animal speciesendemic to Sri Lanka.
The forest complex act as an important catchment area for many rivers and streams flow through the area. The forest is the source for Gin River, which flows west to the forest and for Nilwala river which flows east to the forest. Kanneli, Nanikiththa and Udugama are the smaller streams of Kanneliya while Homa dola and Gal bandi dola are sourced by Nakiyadeniya and Deiyagala.
Flora
The KDN forest complex shows a degree of floral endemicity, as 17 percent of lowland endemic floral species are confined to this forest area. Of 319 woody plants recorded in the area, about 52 per cent is endemic. The vegetation of KDN complex represents Sri Lanka lowland rain forests. The floral communities dominated by Shorea-Dipterocarpus-Mesua are common in emergent layer of the forest. Numerous medicinal plants are found in these forests. They include Coscinium fenestratum, Salacia reticulata, and Tinospora cordifolia. Lycopodium squarrosum, and Lycopodium phlegmaria are among the rare plants the forest complex harbors. The near-threatened Palaquium hinmolpedda is also found here.
Fauna
Some 220 faunal species recorded from the KDN forests and forests around the KDN. This includes 41 endemic species. The forest complex is home to 86 species mammals. This includes 4 species of shrews, 5 rodents, one carnivore and 2 primates. Out of 26 endemic birds of Sri Lanka, 20 of them can be seen in KDN forest complex. Sri Lanka spurfowl, Sri Lanka junglefowl, Sri Lanka grey hornbill, red-faced malkoha, orange-billed babbler, Sri Lanka blue magpie are some of them. 20 percent of Sri Lanka's endemic freshwater fishes inhabit in the waters of Gin River and Nilwala River, which sourced by the springs of Kanneliya-Dediyagala-Nakiyadeniya. Among the forests' herpetofauna are 36 species of snakes, 17 endemic species belonging to 6 families. A total of 23 species of lizards recorded in these rain forests.