Donggi Cona

Donggi Cona
Lake Donggi Cona with ice cover
Donggi Cona is located in Qinghai
Donggi Cona
Donggi Cona
LocationQinghai, China
Coordinates35°17′N 98°32′E / 35.283°N 98.533°E / 35.283; 98.533
Catchment area3,174 km2 (1,225 sq mi)
Basin countriesChina
Surface area229 km2 (88 sq mi)
Max. depth90 m (300 ft)
Surface elevation4,090 m (13,420 ft)

Lake Donggi Cona (also Donggei Cuona or Dongxi Co) is a freshwater lake located 4090 m above sea level at the northeastern Tibetan Plateau.

Geology and water chemistry

The lake basin is a tectonic pull-apart structure situated at the highly active Kunlun fault. It is characterised by a 92 m deep graben structure in the deeper western part of the lake basin, and a more shallow eastern part which is filled up with fluvial sediments.

During different episodes of the last ice age, the lake level was 24 to 57 m lower than today, and the lake was a closed system without outflow. With rising lake levels during the Holocene, an outflow developed ca. 4300 years ago, turning the lake into an open system.[1][2]

Since ca. 6800 years, the lake is an oligotrophic freshwater lake, with oxygen supply down to the lake bottom and a mean pH of 8.6. A higher primary productivity than at present and brackish conditions were inferred for the late glacial to mid Holocene period.[3][4]

Ecology

The vegetation in the lake catchment consists mainly of alpine meadows dominated by Kobresia, Artemisia, and Poaceae. Dunes on the alluvial plains around the lake are characterised by the occurrence of Salix sp.[5]

Literature

  1. ^ Dietze, E.; Wünnemann, B.; Diekmann, B.; Aichner, B.; Hartmann, K.; Herzschuh, U.; IJmker, J.; Jin, H.; Kopsch, C.; Lehmkuhl, F.; Li, S.; Mischke, S.; Niessen, F.; Opitz, S.; Stauch, G. (2010). "Basin morphology and seismic stratigraphy of Lake Donggi Cona, north-eastern Tibetan Plateau, China". Quaternary International. 218 (1–2): 131–142. doi:10.1016/j.quaint.2009.11.035. Archived from the original on 2023-12-02. Retrieved 2023-02-21.{{cite journal}}: CS1 maint: bot: original URL status unknown (link)
  2. ^ Opitz, Stephan; Wünnemann, Bernd; Aichner, Bernhard; Dietze, Elisabeth; Hartmann, Kai; Herzschuh, Ulrike; IJmker, Janneke; Lehmkuhl, Frank; Li, Shijie; Mischke, Steffen; Plotzki, Anna; Stauch, Georg; Diekmann, Bernhard (June 2012). "Late Glacial and Holocene development of Lake Donggi Cona, north-eastern Tibetan Plateau, inferred from sedimentological analysis". Palaeogeography, Palaeoclimatology, Palaeoecology. 337–338: 159–176. doi:10.1016/j.palaeo.2012.04.013.
  3. ^ Aichner, Bernhard; Herzschuh, Ulrike; Wilkes, Heinz; Schulz, Hans-Martin; Wang, Yongbo; Plessen, Birgit; Mischke, Steffen; Diekmann, Bernhard; Zhang, Chengjun (2012). "Ecological development of Lake Donggi Cona, north-eastern Tibetan Plateau, since the late glacial on basis of organic geochemical proxies and non-pollen palynomorphs". Palaeogeography, Palaeoclimatology, Palaeoecology. 313–314: 140–149. doi:10.1016/j.palaeo.2011.10.015. Archived from the original on 15 November 2023. Retrieved 21 February 2023.{{cite journal}}: CS1 maint: bot: original URL status unknown (link)
  4. ^ Mischke, Steffen; Aichner, Bernhard; Diekmann, Bernhard; Herzschuh, Ulrike; Plessen, Birgit; Wünnemann, Bernd; Zhang, Chengjun (2010). "Ostracods and stable isotopes of a late glacial and Holocene lake record from the NE Tibetan Plateau". Chemical Geology. 276 (1–2): 95–103. doi:10.1016/j.chemgeo.2010.06.003.
  5. ^ Kürschner, Harald; Herzschuh, Ulrike; Wagner, Dorothea (2005-12-14). "Phytosociological studies in the north-eastern Tibetan Plateau (NW China) A first contribution to the subalpine scrub and alpine meadow vegetation". Botanische Jahrbücher für Systematik, Pflanzengeschichte und Pflanzengeographie. 126 (3): 273–315. doi:10.1127/0006-8152/2005/0126-0273. ISSN 0006-8152.