Location
The eddy covariance tower was established at an experimental site (42°02'48"N, 116°17'01" E, 1350 m a.s.l) fenced from 2001 at Duolun Restoration Ecology Experimentation and Demonstration Station (42°02'N, 116°17' E, 1324 m a.s.l), which is administrated by the Institute of Botany, Chinese Academy of Sciences, located in the southwest area of Duolun County, Inner Mongolia. The vegetation type belongs to typical semiarid steppes.
Climatic
The study area is semiarid continental climate. The mean annual air temperature is 2.2℃, with a range of temperature from -40℃ to 36℃, and annual precipitation is 381mm. The mean annual relative humidity is 61%, annual sunshine hour is 3400 hours and the average frost-free period is 100 days.
Vegetation and soil
Stipa spp. and Artemisia frigida are the dominant species at this typical steppe ecosystem. The eddy covariance tower site was fenced from 2001 for grazing exclusion and was dominated by Stipa krylovii, Artemisia frigida, Leymus chinensis, Agropyron cristatum and Cleistogenes squarrosa. The height of vegetation is about 30-50cm.
The soil is chestnut soil (FAO classification) with 30cm depth, containing 76.8% sand, 16.7% silt and 6.5% clay. Topsoil organic carbon and total nitrogen ( 0–10 c m) are 15.8g kg-1 and 1.7g kg-1, respectively.
Observation system
The eddy covariance tower was built in May 2005 at a height of 5 m. The open-path eddy covariance system consists of an infrared gas analyzer (LI-7500, LICOR) and a three-dimensional sonic anemometer (CSAT3, CSI) (4 m above ground). The data of wind speed and gas concentration were sampled at 10 Hz. Continuous high frequency data was recorded and the covariance was calculated at 30 min intervals. Net radiation and photosynthetically active radiation were measured at 3.5 m above ground using a four-component net radiometer (CNR-1, Kipp&Zonen) and a quantum sensor (LI190SB, LICOR). Air temperature and relative humidity were measured at three levels (1.5 m, 2 m and 4m) with HMP45C (CSI). Rainfall was recorded continuously by a tipping bucket rain gauge (TE-525, CSI) 4 m above the ground. The top of 10 cm volumetric soil water content was measured by a TDR sensor (CS616, CSI). Soil temperatures were measured with temperature probes (107, CSI) at three soil layers (5, 10 and 20 cm). Soil heat flux was determined with soil heat transducers (HFT-3, CSI) at 2 cm below the soil surface with three replicates. All micrometeorological data was recored every 30 min.
Principal Investigator
Shiping Chen
E-mail: spchen@ibcas.ac.cn
Zhang P, Chen SP, Zhang WL, Miao HX, Chen JQ, Han XG, Lin GH. 2012. Biophysical regulations of NEE light response in a steppe and a cropland in Inner Mongolia. Journal of Plant Ecology-UK, 5: 238-248.
Chen SP*, Chen JQ, Lin GH, Zhang WL, Miao HX, Wei L, Huang JH, Han XG. 2009. Energy balance and partition in Inner Mongolia steppe ecosystems with different land use types. Agricultural and Forest Meteorology. 149:1800-1809.
Miao HX, Chen SP, Chen J, Zhang WL, Zhang P, Wei L, H XG, Lin GH *. 2009. Cultivation and grazing alter evapotranspiration magnitude and dynamics in Inner Mongolia steppes. Agricultural and Forest Meteorology, 149:1810-1819.
Zhang WL, Chen SP, Chen JQ, Wei L, Lin GH*. 2007. Biophysical regulations of carbon fluxes of a steppe and a cultivated cropland in semiarid Inner Mongolia. Agricultural and Forest Meteorology, 146:216-229.