Cambodia - Vietnam, Cambodia, Laos and Northern Thailand - page 568

Environment
The Land
Cambodia's two dominant geographical features are the mighty Mekong River and a vast
lake, the Tonlé Sap. The rich sediment deposited during the Mekong's annual wet-season
flooding has made central Cambodia incredibly fertile. This low-lying alluvial plain is
where the vast majority of Cambodians live - fishing and farming in harmony with the
rhythms of the monsoon.
In Cambodia's southwest quadrant, much of the land mass is covered by the Cardamom
Mountains and, near Kampot, the Elephant Mountains. Along Cambodia's northern border
with Thailand, the plains collide with the Dangkrek Mountains, a striking sandstone es-
carpment more than 300km long and up to 550m high. One of the best places to get a
sense of this area is Prasat Preah Vihear.
In the northeastern corner of the country, in the provinces of Ratanakiri and Mondulkiri,
the plains give way to the Eastern Highlands, a remote region of densely forested moun-
tains and high plateaus.
TONLÉ SAP: THE HEARTBEAT OF CAMBODIA
During the wet season (June to October), the Mekong River rises dramatically, forcing the Tonlé Sap
river to flow northwest into Tonlé Sap (Great Lake). During this period, the lake swells from around
3000 sq km to almost 13,000 sq km, and from the air Cambodia looks like one almighty puddle. An
unbelievable 20% of the Mekong's wet-season flow is absorbed by the Tonlé Sap.
As the Mekong falls during the dry season, the Tonlé Sap river reverses its flow, and the lake's
floodwaters drain back into the Mekong. This extraordinary process makes the Tonlé Sap an ideal
habitat for birds, snakes and turtles, and one of the world's richest sources of freshwater fish.
Wildlife
Cambodia's forest ecosystems were in excellent shape until the 1990s and, compared with
its neighbours, its habitats are still relatively healthy. The years of war took their toll on
some species, but others thrived in the remote jungles of the southwest and northeast.