South Hulsan Lake

Hulsan[1][2][3] or Hollusun Nor[4] is a romanization of a Mongolian name meaning "Reed Lake", from their former abundance in the area.[5] The adjective "south" distinguishes it from nearby North Hulsan Lake.[5] Huoluxun and Huobuxun[lower-alpha 1] are the pinyin romanizations of the Mandarin pronunciation of the same name's transcriptions into Chinese characters. Nan Hulsan or Nanhuobuxun[2] is the same name, prefixed with the Chinese word for "South".

South Hulsan Lake lies in the southern Hulsan subbasin[9] at the eastern edge of the Qarhan Playa in the southeastern corner of the Qaidam Basin[10][7] at an elevation of 2,675.6 m (8,780 ft).[11] It lies east of Tuanjie Lake and south of North Hulsan Lake.[9] It is fed from the east by the Nuomuhong (t 諾木洪河, s 诺木洪河, Nuòmùhóng Hé) and Sulinggele[12] or Suolinguole River.[13]

It usually has an area of 33.41 km² (13 sq mi),[11] but it varies widely during and between years. It usually increases from the winter and spring floods and decreases during the summer and autumn. In 2014, it was as small as 11.33 km² (4 sq mi) and as wide as 91.94 km² (35 sq mi).[3] In the especially dry year of 2000, it was only 0.51 km² (0.2 sq mi).[14] An inflow from the north by mineral springs in the playa's northern karst zone contribute a smaller volume of water[2] but its much higher solute concentration greatly affects the lake and its sediments.[15][16] In the area's hyperarid climate, there is generally only 28–40 mm (1–2 in) of annual rainfall but about 3,000 mm (120 in) of annual evaporation.[2] It is never more than about 1 m (3 ft 3 in) deep.[2]

South Hulsan Lake has gained somewhat since the year 2000 as North Hulsan has shrunk in size to ephemeral status; this is thought to be related to the many salt pans constructed in recent years to harvest the lakes' sediment for potash.[14]

• Qarhan Playa and Qaidam Basin
• List of lakes and saltwater lakes of China