Mackenzie River basins, mostly in Alberta. The cold northern permafrost regions beyond the Arctic Circle are very sparsely populated, mainly by indigenous peoples. Most of the Mackenzie watershed is unbroken wilderness and human activities have little influence on the overall water quality, although there are some localized impacts. Some parts of the Mackenzie basin are rich in natural resources – oil and gas in the Northwest Territories and in central Alberta, lumber in the Peace River headwaters, uranium in Saskatchewan, gold and zinc in the Great Slave Lake area and tungsten in the Yukon. As of 2003 there were two operational gold
Dongting Lake water from the Yangtze flows into the lake, enlarging it greatly. The lake's area, which normally is (data before 1998), may increase to in flood season, when vast amounts of water and sediment from the Chang Jiang flow into the lake. The lake is also fed by four major rivers: the Xiang, Zi, Yuan and Li rivers. Small rivers also flow in, the most famous one being Miluo River where a famous poet Qu Yuan committed suicide. In addition, the Xiao River flows into the Xiang near Yongzhou, before the Xiang flows into the lake. Ocean-going vessels can travel through