The data set contains the flux observation data of large aperture scintillator from daman station in the middle reaches of heihe hydrometeorological observation network.Large aperture scintillators of BLS450 and BLS900 models were installed at daman station in the middle reaches of China. The north tower was the receiving end of BLS900 and the transmitting end of BLS450, and the south tower was the transmitting end and the receiving end of BLS900.The initial observation time of BLS450 is from January 1, 2015 to April 14, 2015, and the observation time of another BLS450 is from June 12, 2015 to December 31, 2015.BLS900 was observed from May 1, 2015 to December 31, 2015.The station is located in dazman irrigation district, zhangye city, gansu province.The latitude and longitude of the north tower is 100.379 E, 38.861 N, and the latitude and longitude of the south tower is 100.369 E, 38.847 N, with an altitude of about 1556m.The effective height of the large aperture scintillator is 22.45m, the optical diameter length is 1854m, and the sampling frequency is 1min. Large aperture flicker meter raw observation data for 1 min, data released for after processing and quality control of data, including sensible heat flux is mainly combined with the automatic meteorological station observation data, based on similarity theory alonzo mourning - Mr. Hoff is obtained by iterative calculation, the quality control of the main steps include: (1) excluding Cn2 reach saturation data (Cn2 e-13 > 1.43);(2) data with weak demodulation signal strength (BLS450: Mininum X Intensity< 50 (2015.1.1-2015.4.14) and Average X Intensity<1000 (2015.6.12-2015.12.31) were excluded.BLS900: Average X Intensity<1000);(3) data at the time of precipitation were excluded;(4) data of weak turbulence under stable conditions were excluded (u* < 0.1m/s).In the iterative calculation process, the stability universal function of Thiermann and Grassl(1992) was selected. Please refer to Liu et al(2011, 2013) for detailed introduction. Some notes on the released data :(1) the middle LAS data is mainly BLS900, the missing time is supplemented by BLS450 observation, and the missing time of both is marked with -6999.4.14-5.1 due to instrument deployment, data is missing.(2) data table head: Date/Time: Date/Time (format: yyyy/m/d h:mm), Cn2: structural parameters of air refraction index (unit: m-2/3), H_LAS: sensible heat flux (unit: W/m2).The meaning of data time, such as 0:30 represents the average between 0:00 and 0:30;The data is stored in *.xls format. Please refer to Li et al. (2013) for hydrometeorological network or site information, and Liu et al. (2011) for observation data processing.
0 2020-03-05
The dataset of ground truth measurements synchronizing with the airborne WiDAS mission was obtained in the Linze station foci experimental area on Jun. 29, 2008. WiDAS, composed of four CCD cameras, one mid-infrared thermal imager (AGEMA 550), and one infrared thermal imager (S60), can acquire CCD, MIR and TIR band data. The simultaneous ground data included: (1) soil moisture (0-5cm) nine times by the cutting ring (50cm^3) along LY06 and LY07 strips, and once by the cutting ring method and once by ML2X Soil Moisture Tachometer in the six points of Wulidun farmland quadrates. The preprocessed soil volumetric moisture data were archived as Excel files. (2) surface radiative temperature measured three times by three handheld infrared thermometer (5# and 6# from Cold and Arid Regions Environmental and Engineering Research Institute, and one from Institute of Geographic Sciences and Natural Resources, which were all calibrated) in LY06 and LY07 strips (98 sample points and repeated three times) and the Wulidun farmland quadrates (various points and repeated three times). Data were archived as Excel files. (3) maize canopy component temperature measured by the 5# handheld infrared thermometer (from Cold and Arid Regions Environmental and Engineering Research Institute) in Wulidun farmland quadrates. Six directions were measured, canopy backlighting and frontlighting, half height backlighting and frontlighting, the light and the shaded bareland, with each direction 20 measurements. (4) spectrum of maize, soil and soil with known moisture measured by ASD Spectroradiometer (350~2 500 nm) from BNU, and the reference board (40% before Jun. 15 and 20% hereafter) in Wulidun farmland quadrates. Raw spectral data were binary files , which were recorded daily in detail, and pre-processed data on reflectance (by ViewSpecPro) were archived as Excel.files (5) mltiangle maize spectrum measured by ASD Spectroradiometer (350~2 500 nm) from BNU, the reference board (40% before Jun. 15 and 20% hereafter), two observation platforms of BNU make and one of Institute of Remote Sensing Applications make in Wulidun farmland. Raw spectral data were archived as binary files, which were recorded daily in detail, and pre-processed data on reflectance and transmittivity were archived as text files (.txt). (6) LAI of maize measured by the fisheye camera (CANON EOS40D with a lens of EF15/28), shooting straight downwards, with exceptions of higher plants, which were shot upwards. Data included original photos (.JPG) and those processed by can_eye5.0 (in excel). (7) LAI of maize measured by LAI2000 in Wulidun farmland quadrates. Data educed from LAI2000 periodically were archived as text files (.txt) and marked with one ID. Raw data (table of word and txt) and processed data (Excel) were included. Besides, observation time, the observation method and the repetition were all archived. See the metadata record “WATER: Dataset of setting of the sampling plots and stripes in the Linze station foci experimental area” for more information of the quadrate locations.
0 2019-05-23
The data set of prokaryotic microorganism distribution in the snow and ice of the Arctic Antarctic and the Tibetan Plateau provides the bacterial 16S ribosomal RNA gene sequence collected by the experimental group led by Yongqin Liu from the NCBI database during 2010 to 2018. The keywords for NCBI database search are Antarctic, Arctic Tibetan, and Glacier. The collected sequences were calculated using the DOTOUR software to obtain the similarities between sequences, the sequences with similarities above 97% were clustered into one OTU, and the OTU representative sequence was defined. The OTU representative sequence was compared with the RDP database by the "Classifier" software and was identified as level one when the reliability exceeded 80%. After acquiring the sequence, the GPS coordinates of the sample were obtained by reading the sample information in the sequence file. These data contain the sequence of 16S ribosomal RNA gene fragments for each sequence, evolutionary classification, and sample GPS coordinates. Compared with sequences based on high-throughput sequencing, these data have a longer sequence and more accurate classification. It is significant for comparing the evolutionary information of three-pole microorganisms and understanding the evolution of psychrophilic microorganisms.
0 2020-06-03
The hydrological monitoring of Picea crassifolia and main shrub vegetation types, including canopy interception, soil moisture content and stemflow, was carried out at different altitude gradients in Pailugou catchment of Qilian Mountain. The monitoring time was the dynamic monitoring of growth season in 2012 and 2013.
0 2020-03-12
On the basis of physiological and biochemical analysis of photosynthetic organs (leaves or assimilating branches) of typical desert plants in heihe river basin collected in mid-july 2011, some photosynthetic organs of desert plants were collected in mid-july 2012 and put into a liquid nitrogen tank and brought back to the laboratory for determination. Physiological analysis indexes mainly include: soluble protein unit: mg/g;Free amino acid unit: g/g;Chlorophyll content unit: mg/g;Superoxide dismutase (SOD) unit: U/g FW;Catalase (CAT) unit: U/(g•min);POD unit: U/(g•min);Proline (Pro) unit: g/g; Soluble sugar unit: g/g;Malondialdehyde (MDA) is given in moles per liter.
0 2020-03-10
The data set of atmospheric water vapor absorption and utilization of desert plants, all of which are original data, including the liquid flow and environmental data of wild desert plants (Sitan village and Ejina Banner, Jingtai County), such as Tamarix, Bawang, Baici, Hongsha, etc., including the data of meteorology, photosynthesis, fluorescence and leaf surface humidity, as well as the data of gene transcriptome and expression regulation.
0 2020-07-31
The third pole 1:100,000 range data set includes:Mountains(Tibet_Mountains)vector space data set and its attribute name:Name(Name)、Countries Name(CNTRY_NAME)、Countries Referred to as(CNTRY_CODE)、Latitude(LATITUDE)、Longitude(LONGITUDE). The data comes from the 1:100,000 ADC_WorldMap global data set,The data through topology, warehousing and other data quality inspection,Data through the topology, into the library,It's comprehensive, up-to-date and seamless geodigital data. The world map coordinate system is latitude and longitude, D_WGS_1984 datum surface
0 2020-05-28
The medium-resolution MODIS river and lake ice phenology data set in the high latitudes of the northern hemisphere from 2002 to 2019 is based on the Normalized Difference Snow Index (NDSI) data of the Moderate Resolution Imaging Spectroradiometer(MODIS). Daily lake iceextent and coverage under clear-sky conditions was examined byemploying the conventional SNOWMAP algorithm, and thoseunder cloud cover conditions were re-determined using the temporal and spatial continuity of lake surface conditions througha series of steps.The lake ice phenology information obtained in this dataset was highly consistent with that from passive microwave data at an average correlation coefficient of 0.91 and an RMSE value varying from 0.07 to 0.13.
0 2020-08-05
The dataset of vegetation cover fraction observations was obtained by the self-made instrument and the camera at a height of 2.5m-3.5m above the ground in the Yingke oasis, Huazhaizi desert steppe and Biandukou foci experimental areas on May 20, 24, 25, 28 and 30, Jun. 11, 14, 15, 21, 23, 24, 27 and 30, and Jul. 2, 2008. Observations were carried out in Yingke oasis maize field, Yingke oasis wheat field, Huazhaizi desert No. 1 and 2 plots, the rape field, the barley field and grassland in Biandukou. A pole with known length was put in each photo to determine the size of the photo. GPS data was used for the location and the technology LAB was used to retieve the coverage of the green vegetation. Besides, surrounding environment was also recorded. The dataset included the primary collected vegetation images and retrieved fraction of vegetation coverage.
0 2019-09-13
This dataset contains the flux measurements from the Huazhaizi desert station eddy covariance system (EC) in the middle reaches of the Heihe hydrometeorological observation network from 24 September, 2012, to 31 December, 2013. The site (100.319° E, 38.765° N) was located in the desert steppe surface, near Zhangye city in Gansu Province. The elevation is 1731 m. The EC was installed at a height of 2.85 m, and the sampling rate was 10 Hz. The sonic anemometer faced north, and the separation distance between the sonic anemometer and the CO2/H2O gas analyzer (CSAT3&Li7500) was 0.15 m. The raw data acquired at 10 Hz were processed using the Edire post-processing software (University of Edinburgh, http://www.geos.ed.ac.uk/abs/research/micromet/EdiRe/), including the spike detection, lag correction of H2O/CO2 relative to the vertical wind component, sonic virtual temperature correction, coordinate rotation (2-D rotation), corrections for density fluctuation (Webb-Pearman-Leuning correction), and frequency response correction. The EC data were subsequently averaged over 30 min periods. The observation data quality was divided into three classes according to the quality assessment method of stationarity (Δst) and the integral turbulent characteristics test (ITC), as proposed by Foken and Wichura [1996]: class 1 (level 0: Δst<30 and ITC<30), class 2 (level 1: Δst<100 and ITC<100), and class 3 (level 2: Δst>100 and ITC>100), which represent high-, medium-, and low-quality data, respectively. In addition to the above processing steps, the half-hourly flux data were screened using a four-step procedure: (1) data from periods of sensor malfunction were rejected; (2) data collected before or after 1 h of precipitation were rejected; (3) incomplete 30 min data were rejected when the missing data constituted more than 3% of the 30 min raw record; and (4) data were rejected at night when the friction velocity (u*) was less than 0.1 m/s. There were 48 records per day, and the missing data were replaced with -6999. Suspicious data were marked in red. The 10 Hz data were missing during 8 December to 22 December, 2012, and data in this period were replaced with 30 min flux output by data logger. Due to the malfunction of data logger in July, the 10 Hz data were missing, and data during this period were replaced by the 30 min data logger output data. The released data contained the following variables: data/time, wind direction (Wdir, °), wind speed (Wnd, m/s), the standard deviation of the lateral wind (Std_Uy, m/s), virtual temperature (Tv, ℃), H2O mass density (H2O, g/m^3), CO2 mass density (CO2, mg/m^3), friction velocity (ustar, m/s), stability (z/L), sensible heat flux (Hs, W/m^2), latent heat flux (LE, W/m^2), carbon dioxide flux (Fc, mg/ (m^2s), quality assessment of the sensible heat flux (QA_Hs), quality assessment of the latent heat flux (QA_LE), and quality assessment of the carbon flux (QA_Fc). In this dataset, the time of 0:30 corresponds to the average data for the period between 0:00 and 0:30; the data were stored in *.xls format. For more information, please refer to Li et al. (2013) (for hydrometeorological observation network or sites information), Liu et al. (2011) (for data processing) in the Citation section.
0 2019-09-14
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