Tonlé Sap, actually extensive waterway crisp, not salty, alludes to an occasionally immersed freshwater lake, the Tonlé Sap Lake and an appended stream, the 120 km (75 mi) long Tonlé Sap River, that interfaces the lake to the Mekong River. They shape the focal piece of a complex hydrological framework, arranged in the 12,876 km2 (4,971 sq mi) Cambodian floodplain secured with a mosaic of regular and rural living spaces that the Mekong recharges with water and dregs yearly. The focal plain development is the consequence of a huge number of years of Mekong alluvial testimony and release. From a topographical viewpoint, the Tonlé Sap Lake and Tonlé Sap River are a momentum solidify outline portrayal of the gradually, yet continually moving Lower Mekong Basin.
The Tonlé Sap Lake involves a topographical sorrow (the most minimal lying range) of the immense alluvial and lacustrine floodplain in the Lower Mekong Basin, which had been prompted by the impact of the Indian Plate with the Eurasian Plate. The lake's size, length and water volume shifts impressively through the span of a year from a zone of around 2,500 km2 (965 sq mi), a volume of 1 km3 (0.24 cu mi) and a length of 160 km (99 mi) toward the finish of the dry season in late April to a territory of up to 16,000 km2 (6,178 sq mi), a volume of 80 km3 (19 cu mi) and a length of 250 km (160 mi) as the Mekong most extreme and the pinnacle of the South-West storm's precipitation come full circle in September and early October.
As one of the world's most changed and profitable biological systems the district has dependably been of focal significance for Cambodia's nourishment arrangement. It demonstrated able to do to a great extent keeping up the Angkorean human progress, the biggest pre-mechanical settlement complex in world history. Either specifically or by implication it influences the job of expansive quantities of a dominatingly rustic populace right up 'til today. With respect to a developing and moving populace, incapable organization and across the board lack of concern towards natural issues the lake and its encompassing environment is going under expanding weight from over-abuse and territory corruption, discontinuity and misfortune. All Mekong riparian states have either declared or officially executed arrangements to progressively abuse the waterway's hydroelectric potential. A progression of global offices that dam the waterway's standard is probably going to be the gravest peril yet for the whole Tonle Sap eco-district.
The biggest freshwater lake in Southeast Asia, that contains an outstanding extensive assortment of interconnected eco-districts with a high level of biodiversity is a biodiversity hotspot and was assigned as an UNESCO biosphere hold in 1997.