Location

 The Damxung flux observation site is one of ChinaFlux stations on the Tibetan Plateau. It is located at 30º29′50.21″N, 91º03′58.90″E with altitude of 4330 m, in south edge of Nyainqêntanglha Range. This station belongs to the Damxung Alpine Meadow Ecosystem Experimental Station, Institute of Geographic Science and Natural Resources Research, Chinese Academy of Sciences. It represents a vegetation of dominate by Kobresia-Steppe in the transition zone of alpine meadow and alpine steppe.

Climatic

 The site has a continental monsoon climate characterized by long cold winters and short cool summers. The mean annual temperature is 1.3℃, with a minimum of -10.4℃ in January and a maximum of 10.7℃ in July. Annual precipitation is 470 mm, about 85% of which falls from June to August. The plant growing reason lasts about 100 days. Annual gross solar radiation is 7527.6 MJ.m^-2 and photosynthetically active radiation is 3213.3 MJ.m^-2.

Vegetation and soil

 The vegetation of Kobresia-steppe meadow is dominated by Kobresia pygmaea C. B., Stipa capillacea Keng and Carex montis-everestii Kükenth dominate the meadows, accompanied by other tussock sedges, grasses and herbs, all of which provide about 50-80% vegetation cover depending on annual precipitation. The soil is Mat-Gryic Cambisol soil, corresponding to a Gelic Cambisol with soil layer about 30 to 50 cm. The contents of soil organic matter and soil nitrogen are 0.9-2.79% and 0.05-0.19% respectively.

Observation system

 OPEC eddy covariance observation system, consisting of CSAT3 ultrasonic wind velocity （Campbell, USA）and Li7500 CO₂/H₂O analyzer (Li-cor, USA)，were mounted at the height 2 m in the tower in the site in July 2003. The data logger collects CO₂/H₂O fluxes with frequency of 10 Hz. A system of microclimate system is also integrated to routine climatic factor monitoring. In addition, chamber measurement system is also used to measure the greenhouse gases emission in the growing season.

Principal Investigator

Peili Shi

E-mail: shipl@igsnrr.ac.cn