Current Browsing: Heihe River Basin


Downscaling simulations of future temperature based on CMIP5 outputs in Heihe river basin (2011-2100)

Based on the downscaling temperature result data in the historical period of CMIP5 (Coupled Model Intercomparison Project Phase 5), the future multi-year average temperature in the three periods of 2011-2040, 2041-2070, and 2071-2100 was predicted. Under the scenarios of rcp2.6, rcp4.5, and rcp8.5, the method of combining ordinary least squares regression with HASM (High Accuracy Surface Modeling Method) was used to downscaling simulate and predict, and the 1km downscaling results of the multi-year average temperature in the three scenarios of 2011-2040, 2041-2070 and 2071-2100 were obtained.

2020-03-02

Validation dataset of ecological model in the Heihe River Basin (2018)

This data set is collected according to the output results of tesim ecological process model, including biomass, plant N and P content, evapotranspiration, NPP and other model output results. Some of the results are obtained by field measurement, some by laboratory analysis of field samples, some by literature.

2020-03-02

Landscape structure changes dataset of the terminal lakes and wetlands of the China's Heihe River Basin in the recent 50 years

Taking Landsat series data as the main data source, including KH in 1965 (only including Gurinai and Guaizi Lake), MSS in 1975, TM in 1990, 1995, 2006 and 2010, and ETM in 2000. Before information extraction, remote sensing images are preprocessed by image synthesis, mosaic, fusion, geometric correction and image enhancement. In the process of correction, ETM + image in 2000 is corrected by 1:100000 topographic map and used as reference image. The 4, 3 and 2 band standard pseudocolor synthesis scheme is selected for image synthesis; during correction, 7 × 8 control points are evenly selected on each image, and the average positioning error is less than 1 pixel, that is, the ground distance is less than 30m. In other years, the datum image of 2000 is used as the reference image for image registration, so that the pixels with the same name on different images have the same geographical coordinates. After correction and registration, the whole image maintains the 30 m spatial resolution of TM. Through field correction, the accuracy of qualitative analysis can be ensured to be over 95%.

2020-02-21

The response of grassland productivity to soil moisture under grazing disturbance in Heihe Basin

The data include different observation data of Sunan, Gansu Province: 1) The soil properties of grassland under different management measures, soil compactness, water permeability and soil moisture content of 4-5 grazing intensity grassland; 2) The observation data of soil compactness, permeability and water content of different grazing management measures; 3) Correlation analysis data of grassland community characteristic productivity and soil moisture; 4) Correlation analysis data of height, coverage, biomass, flower shape, tiller and leaf characters of main plants with soil water content;

2020-02-20

The observational data of photosynthetic physiological and moisture physiology of desert dominant species from Jun to Jul, 2014

In the late June and early July of 2014, the dominant species of desert plants in the lower reaches of Heihe River, Lycium barbarum and Sophora alopecuroides, were selected. Using the LI-6400 portable photosynthesis system (LI-COR, USA), the photosynthetic and water physiological characteristics of desert plants were measured and analyzed.

2020-01-10

Observation dataset of maize photosynthesis in the irrigating areas of the midstream of the Heihe River Basin (2012)

This data is based on the observation of corn in the middle reaches of heihe river irrigated area. The observation instrument is licor-6400 XTR and the site is selected near the HiWATER combined test superstation.The photosynthesis parameters of maize were observed through uncontrolled experiments and controlled experiments (controlling carbon dioxide and light intensity) from June 22, 2012 to August 24, 2012.

2019-12-27

HiWATER: Dataset of flux observation matrix (NO.1 large aperture scintillometer) of the MUlti-Scale Observation EXperiment on Evapotranspiration over heterogeneous land surfaces 2012 (MUSOEXE-12)

This dataset contains the flux measurements from the large aperture scintillometer (LAS) at site No.1 in the flux observation matrix. There were two types of LASs at site No.1: German BLS900 and China zzlas. The observation periods were from 7 June to 19 September, 2012, and 16 June to 19 September, 2012, for the BLS900 and the zzlas, respectively. The north tower is placed with the receiver of BLS900 and the transmitter of zzlas, and the south tower is placed with the transmitter of BLS900 and the receiver of zzlas. The site (north: 100.352° E, 38.884° N; south: 100.351° E, 38.855° N) was located in the Yingke irrigation district, which is near Zhangye, Gansu Province. The elevation is 1552.75 m. The underlying surface between the two towers contains corn, greenhouse, and village. The effective height of the LASs was 33.45 m; the path length was 3256 m. Data were sampled at 1 min intervals. Raw data acquired at 1 min intervals were processed and quality-controlled. The data were subsequently averaged over 30 min periods. The main quality control steps were as follows. (1) The data were rejected when Cn2 was beyond the saturated criterion (Cn2>3.05E-14). (2) Data were rejected when the demodulation signal was small (BLS900: Average X Intensity<1000; zzlas: Demod<-40 mv). (3) Data were rejected within 1 h of precipitation. (4) Data were rejected at night when weak turbulence occurred (u* was less than 0.1 m/s). The sensible heat flux was iteratively calculated by combining with meteorological data and based on Monin-Obukhov similarity theory. There were several instructions for the released data. (1) The data were primarily obtained from BLS900 measurements; missing flux measurements from the BLS900 were filled with measurements from the zzlas. Missing data were denoted by -6999. (2) The dataset contained the following variables: data/time (yyyy-mm-dd hh:mm:ss), the structural parameter of the air refractive index (Cn2, m-2/3), and the sensible heat flux (H_LAS, W/m^2). (3) 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 *.xlsx format. Moreover, suspicious data were marked in red. For more information, please refer to Liu et al. (2016) (for multi-scale observation experiment or sites information), Xu et al. (2013) (for data processing) in the Citation section.

2019-09-15

HiWATER: Dataset of hydro-meteorological observation network (eddy covariance system of Barren-land Station, 2015)

The data set contains eddy covariance System observation data of Barren-land Station which is located in the lower reaches of the Heihe Hydro-meteorological Observation Network from January 1, 2015 to December 31, 2015. The site is located in Sidaoqiao, Ejina Banner, Inner Mongolia, and the underlying surface is barren land. The latitude and longitude of the observation point is 101.1326E, 41.9993N, and the altitude is 878m. The mount height of the Eddy Covariance System is 3.5 m, the sampling frequency is 10 Hz, the ultrasonic orientation is north, and the distance between the ultrasonic wind speed temperature meter (CSAT3) and the CO2/H2O analyzer (Li7500) is 15 cm. The original observation data of the Eddy Covariance System is 10 Hz, and the released data is a 30-minute data processed by Eddypro software. The main steps of the processing include: outlier eliminating, delay time correction, coordinates rotation (secondary coordinates rotation), frequency response correction, ultrasonic virtual temperature correction and density (WPL) correction, etc. Meanwhile, the quality evaluation of each flux value was performed,mainly includes atmospheric stability (Δst) test and turbulence similarity (ITC) test. The 30-min flux value output of Eddypro software was also screened: (1) Data from the instrument error was eliminated; (2) Data obtained with one hour before and after precipitation was removed; (3) Data with a deletion rate greater than 10% of the 10 Hz raw data every 30 minutes was eliminated; (4) Observation data of weak turbulence at night (u* less than 0.1 m/s) was excluded. The average period of observation data is 30 minutes, 48 data per day, and the missing data is marked as -6999. The data was missing due to Li7500 calibration of the eddy system on April 7 and 8; the suspicious data caused by instrument drift and other reasons was marked by red fonts. Published observation data include: date/time Date/Time, wind direction(°), horizontal wind speed(m/s), lateral wind speed standard deviation(m/s), ultrasonic virtual temperature (°C), water vapor density (g/m3), carbon dioxide concentration(mg/m3), friction velocity (m/s), length (m), sensible heat flux(W/m2), latent heat flux (W/m2), carbon dioxide flux (mg/(m2s)), sensible heat flux quality identification QA_Hs, latent heat flux quality identification QA_LE, carbon dioxide flux quality identification QA_Fc. The quality identification of sensible heat, latent heat, and carbon dioxide flux is divided into three levels (quality mark 0: (Δst <30, ITC<30); 1: (Δst <100, ITC<100); the rest is 2). The meaning of the data time, such as 0:30 represents an average data of 0:00-0:30; the data is stored in *.xls format. For hydro-meteorological network or station information, please refer to Li et al. (2013). For observation data processing, please refer to Liu et al. (2011).

2019-09-15

HiWATER: Dataset of ground truth measurements synchronizing with airborne PLMR mission in the Yingke oasis and Huazhaizi desert steppe on June 28-29, 2012

The first dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in the Yingke oasis and Huazhaizi desert steppe on 28-29 June, 7, 10, 26 July, 2 August, 2012 (UTC+8). The dataset of ground truth measurements synchronizing with airborne Polarimetric L-band Multibeam Radiometer (PLMR) mission was obtained in the Linze Inland River Basin Comprehensive Research Station on 3 July, 2012. PLMR is a dual-polarization (H/V) airborne microwave radiometer with a frequency of 1.413 GHz, which can provide multi-angular observations with 6 beams at ±7º, ±21.5º and ±38.5º. The PLMR spatial resolution (beam spot size) is approximately 0.3 times the altitude, and the swath width is about twice the altitude. The measurements were conducted in the southwest part of the Zhangye Oasis, which included two sampling plots. One was located in Gobi desert with an area of 1 km × 1 km. Due to its homogeneous landscape, around 10 points were sampled to acquire the situation of soil water content. The other sampling plot was designed in farmlands with a dominant plant type of maize. Ground measurements took place along 16 transects, which were arranged parallelly with an interval of 160 m between each other in the east-west direction. In each 2.4 km long transect, soil moisture was sampled at every 80 m in the north-south direction. Steven Hydro probes were used to collect soil moisture and other measurements. For each sampling point in farmland, two measurements were acquired within an area of 1 m2, with one for the soil covered by plastic film (point name was tagged as LXPXXA) and the other for exposed soil (point name was tagged as LXPXXB). The field campaign started from 11:00 AM, but stopped at 4:00 PM on 28 June because of rain. The rest of measurements were completed from 10:30 AM to 5:30 PM on 29 June. Concurrently with soil moisture sampling, vegetation properties were measured at around 10 locations within the farmland sampling plot. Observation items included: Soil parameters: volumetric soil moisture (inherently converted from measured soil dielectric constant), soil temperature, soil dielectric constant, soil electric conductivity. Vegetation parameters: biomass, vegetation water content, canopy height. Data and data format: This dataset includes two parts of measurements, i.e. soil and vegetation parameters. The former is as shapefile, with measured items stored in its attribute table. The measured vegetation parameters are recorded in an Excel file.

2019-09-15

HiWATER: Dataset of hydrometeorological observation network (No.6 runoff observation system of Gaoya hydrological station, 2013)

The No. 6 hydrological section is located at Gaoya Hydrological Station (100.433° E, 39.135° N, 1420 m a.s.l.) in the midstream of the Heihe River Basin, Zhangye city, Gansu Province. This hydrological section is for intercomparison of flow measurement between ADCP and manual method. The dataset contains recorded by the No. 6 hydrological section from 10 August, 2012 to 31 December, 2013. The width of this section is 58 meters. The water level was measured using an HOBO pressure range and the discharge was measured using cross-section reconnaissance by the StreamPro ADCP. The dataset includes the following parameters: water level (recorded every 30 minutes) and discharge. The missing and incorrect (outside the normal range) data were replaced with -6999. For more information, please refer to Li et al. (2013) (for hydrometeorological observation network or sites information), He et al. (2016) (for data processing) in the Citation section.

2019-09-15