SBR- Content.pmd - INBO

2 - Physical landforms of the Mekong Basinseason the flow reverses and water fromthe lake flows southeast to Phnom Penh,where it meets the Mekong mainstream andthe Bassac at Chuktomuk junction.The river branches at Phnom Penh, with theBassac forming the western arm of the delta,and the Mekong proper forming the easternarm. The delta area extends across some65,000 km². In the upper delta, the riverchannels are lined by natural levees formedthrough silt deposition. Lower down withinthe Vietnamese section of the delta, there isan elaborate network of canals.During the rainy season, the area of open water inTonle Sap Great Lake increases from approximately2500 km 2 to 13,000 km 26. Southern UplandsThe southern uplands of southeastern Cambodia constitute one of the extensions of the NorthernHighlands. They include the Cardamom and Elephant ranges, and consist of granite ridges with amaximum altitude of just over 1,800 m. Both these ranges are still densely forested, with lowpopulation densities, and are considered significant areas for conservation.11