Groundwater is the main water source of desert riparian plants, and also the most important environmental factor affecting the normal physiological status of plants. In this project, an observation field was set up in Populus euphratica forest near the Alxa Desert eco hydrological experimental research station from 2011 to 2013 By manually measuring the groundwater depth every month in the year, it can provide basic data support for the study on the transpiration water consumption mechanism of Populus euphratica, and also can be used for the estimation of ecological water demand in the study area.
2020-03-06
SPAC system is a comprehensive platform for observation of plant transpiration water consumption and environmental factors. In this project, a set of SPAC system is set up in the Alxa Desert eco hydrological experimental study. The main observation data include temperature, relative humidity, precipitation, photosynthetic effective radiation, etc. the sampling frequency is one hour. This data provides basic data support for the study of plant transpiration water environmental response mechanism.
2020-03-06
The dataset investigated the growth status of plants and leaf morphological indexes of single and conjoined red sand and pearl in the middle and lower reaches of heihe river basin in 2013. The growth indexes were crown width, plant height, and biomass of fine roots and thick roots.Leaf shape indicators are: length, width, thickness, and leaf area, volume, etc.The experimental observation indexes are: leaf nitrogen content, water potential, gas exchange data, chlorophyll fluorescence data. Data include: field observation data and explanatory documents.
2020-03-05
The data set contains the data of thermal diffusion fluid flow meter in the hydrometeorological observation network from January 1 to December 31, 2015. The study area is located in huyang forest, ejin banner, alxa league, lower reaches of heihe, Inner Mongolia autonomous region.According to the different height and diameter at breast height of iminqak, choose install Thermal diffusion flow meter sample tree (Thermal Dissipation SAP flow velocity Probe, TDP), domestic TDP pin type Thermal diffusion plant flow meter, model for TDP30.The TDP1 point and TDP2 point of sample plots were set in the vicinity of mixed forest station and populus populus station, respectively.Sample tree height from high to low in turn for TDP2 (16.4 meters, 18.3 meters, 16.9 meters), TDP1 (12.5 meters, 13 meters, 14 meters), diameter at breast height order from large to small is TDP1 (48 cm, 41.6 cm, 46.6 cm), TDP2 (33.8 cm, 38.5 cm, 42.3 cm), density of TDP1 respectively (0.0158 per square meter) tree, TDP2 (0.0116 per square meter), to represent the whole area of populus euphratica transpiration measurement.Two sets of probes are installed in each sample tree, with a height of 1.3 meters and a direction of east and west of the sample tree. The original observation data of TDP is the temperature difference between the probes, and the collection frequency is 10s, with an average output of 10 minutes.The published data are calculated and processed trunk flow data, including flow rate V (cm/h), flux Fs (cm3/h) and daily transpiration Q (mm/d) per 10 minutes.Firstly, the liquid flow rate and liquid flux were calculated according to the temperature difference between the probes, and then the transpiration Q per unit area of the forest zone was calculated according to the area of Euphrates poplar forest and the distance between trees at the observation points.At the same time, post-processing was carried out on the calculated rate and flux value :(1) data that obviously exceeded the physical significance or the instrument range were removed;(2) the missing data is marked with -6999;(3) suspicious data caused by probe fault or other reasons shall be identified in red, and the data confirmed to have problems shall be removed. Please refer to Li et al. (2013) for hydrometeorological network or site information, and Qiao et al. (2015) for observation data processing.
2020-03-05
From May 25, 2012 to September 8, 2012, observation was made at 3100m grassland weather station in Tianlaochi watershed of Qilian mountain. The instrument was a 20cm evaporating dish, a round metal basin with a diameter of 20 cm and a height of 10 cm. The mouth of the basin was blade-shaped. In order to prevent birds and animals from drinking water, a trumpet-shaped wire mesh ring was sleeved on the upper part of the mouth. During measurement, the instrument shall be placed on the shelf with the mouth 70cm from the ground, and quantitative clear water shall be put in every day. After 24 hours, the remaining water quantity shall be measured by the dosage cup, and the reduced water quantity shall be the evaporation capacity. Data are daily evaporation from May 25, 2012 to September 8, 2012.
2020-03-04
From June 10, 2011 to September 2, 2011, the observation instrument of 3100m grassland weather station in Tianlaochi watershed of Qilian mountain was a 20cm evaporating pan, a round metal basin with a diameter of 20 cm and a height of 10 cm, and the mouth of the basin was blade-shaped. In order to prevent birds and animals from drinking water, a trumpet-shaped wire mesh ring was set on the upper part of the mouth of the vessel. During measurement, the instrument shall be placed on the shelf with the mouth 70cm from the ground, and quantitative clear water shall be put in every day. After 24 hours, the remaining water quantity shall be measured by the dosage cup, and the reduced water quantity shall be the evaporation capacity. Data are daily evaporation from June 10, 2011 to September 2, 2011.
2020-03-04
In the middle of July and August 2012, mass photosynthesis was determined and the plant species was caragana korshinskii. The mass photosynthesis measurement system is composed of li-8100 closed-circuit automatic soil carbon flux measurement system (li-cor, USA) and an assimilation box designed and manufactured by Beijing liaotai technology co., LTD. Li-8100 is an instrument for soil carbon flux measurement produced by li-cor, USA, which USES an infrared gas analyzer to measure CO2 and H2O concentrations.The length, width and height of the assimilation box are all 50cm.The assimilation box is controlled by li-8100, and the instrument can operate automatically after the measurement parameters are set. The photosynthetic rate of population was calculated according to the following formula: CAP (Canopy growth Rate) is the Photosynthetic Rate of the population (mol CO2•m -- 2•s -- 1).A is the total leaf area (m2) of the plant canopy;VA is the total volume (m3) of the population photosynthesis measurement system, which is the product of the height of the assimilation box from the ground (the distance between the upper edge and the inner ground after the special base is placed), the soil area (0.25 m2) and the sum of the volume of the assimilation box (0.125 m3).Is the change rate of CO2 measured by assimilation chamber (mol CO2•mol -- 1•s -- 1) in the process of population photosynthesis measurement;Is the CO2 change rate (mol CO2•mol -- 1•s -- 1) measured in a 20 cm measuring chamber during the soil respiration measurement process;P is atmospheric pressure (Pa), T is the air temperature in the assimilation chamber (℃), and R is the gas constant (8.314 Pa•m3•mol-1• k-1).N is the conversion coefficient, which means the change rate of CO2 caused by soil respiration in the soil area (SA) covered by the assimilation box and in the total volume (VA) of the population photosynthesis measurement system is converted from the measurement in the 20cm measurement chamber, and calculated according to the following formula: SA is assimilation box cover soil area, 0.25 m2, SC is 20 cm soil area of the measuring chamber cover (0.03 m2), VC is plant roots and soil respiration measurement system of the total volume (m3), to 20 cm measurement chamber high from the ground (after ring on measuring the soil in place along with the internal distance) on the ground and soil area is the product of the (SC) and 20 cm measurement chamber volume (4.82 x 10-3 m3) combined.
2020-03-04
The data set includes the observation data of river water level and velocity at No.7 point in the dense observation of runoff in the middle reaches of Heihe River from January 1, 2015 to March 11, 2016. The sensor was abnormal at the end of 2014, and the commissioning was normal on March 25 after maintenance. The observation point is located in Heihe bridge, Pingchuan Township, Linze County, Zhangye City, Gansu Province. The riverbed is sandy gravel with unstable section. The longitude and latitude of the observation point are n39.331667 °, e100.099722 °, altitude 1375 meters, and channel width 130 meters. In 2015, sr50 ultrasonic distance meter was used for water level observation, with acquisition frequency of 30 minutes. Data description includes: Water level observation, observation frequency 30 minutes, unit (cm); The missing data are uniformly represented by the string -6999. For information of hydrometeorological network or station, please refer to Li et al.(2013), and for observation data processing, please refer to He et al.(2016).
2020-03-03
The data set includes the observation data of river water level and velocity at No.7 point in the dense observation of runoff in the middle reaches of Heihe River from January 1, 2014 to December 28, 2014. The observation point is located in Heihe bridge, Pingchuan Township, Linze County, Zhangye City, Gansu Province. The riverbed is sandy gravel with unstable section. The longitude and latitude of the observation point are n39 ° 20'2.03 ", E100 ° 5'49.63", with an altitude of 1375m and a channel width of 130m. In 2014, sr50 ultrasonic distance meter was used for water level observation, with acquisition frequency of 30 minutes. Data description includes the following two parts: Water level observation, observation frequency 30 minutes, unit (cm); The data covers the period from January 1, 2014 to December 28, 2014. Flow observation, unit (m3); According to the monitoring flow of different water levels, the flow curve of water levels was obtained, and the change process of runoff was obtained by observing the process of water levels.The missing data are uniformly represented by the string -6999. For information of hydrometeorological network or station, please refer to Li et al.(2013), and for observation data processing, please refer to He et al.(2016).
2020-03-03
The data set includes the river level observation data of No. 4 point in the dense runoff observation of the middle reaches of Heihe River from May 20, 2015 to March 11, 2016. The instrument maintenance was completed again on May 20, 2015. The observation point is located in Heihe bridge, Shangbao village, Jing'an Township, Zhangye City, Gansu Province. The riverbed is sandy gravel with unstable section. The longitude and latitude of the observation point are n39.065 °, e100.433056 °, 1431m above sea level, and 58m wide river channel. In 2012, hobo pressure type water level gauge was used for water level observation with acquisition frequency of 30 minutes; since 2013, sr50 ultrasonic distance meter was used with acquisition frequency of 30 minutes. On June 25, 2014, the instrument was damaged and re purchased. The record was restarted on May 20, 2015. The data includes the following parts: Water level observation, observation frequency 30 minutes, unit (cm); For information of hydrometeorological network or station, please refer to Li et al.(2013), and for observation data processing, please refer to He et al.(2016).
2020-03-03
Contact Support
Northwest Institute of Eco-Environment and Resources, CAS
0931-4967287
poles@itpcas.ac.cn
Links
National Tibetan Plateau Data CenterFollow Us
A Big Earth Data Platform for Three Poles © 2018-2020 No.05000491 | All Rights Reserved
｜ 
No.11010502040845
Tech Support: westdc.cn
