Current Browsing: Photosynthetically active radiation


HiWATER: Dataset of vegetation FPAR in the middle of Heihe River Basin form May to July, 2015

This dataset is the FPAR observation in the artificial oasis experimental region of the middle stream of the Heihe River Basin. The observation period is from 24 May to 19 July, 2012 (UTC+8). Measurement instruments: AccuPAR (Beijing Normal University) Measurement positions: Core Experimental Area of Flux Observation Matrix 18 corn samples, 1 orchard sample, 1 artificial white poplar sample Measurement methods: For corn, to measure the incoming PAR on the canopy, transmission PAR under the canopy, reflected PAR on the canopy, reflected PAR under the canopy. For orchard and white poplar forest, to measure the incoming PAR outside of the canopy, transmission PAR under the canopy. Corresponding data: Land cover, plant height, crop rows identification

2021-07-26

Heihe 30m FAPAR production (2012)

Image format: tif Image size: about 925M per scene Time range: may-october 2012 Time resolution: month Spatial resolution: 30m The algorithm firstly adopts the canopy BRDF model and presents the canopy reflectivity as a function of a series of parameters such as FAPAR, wavelength, reflectance of soil and leaves, aggregation index, incidence and observation Angle.The parameter table is established for several key parameters as the input of inversion.Then input the pre-processed surface reflectance data and land cover data, and invert LAI/FAPAR products by look-up table (LUT) method. See references for detailed algorithm.

2020-03-15

Hulugou basin base camp integrated environmental observation system data set (2012)

1. Data overview The data set of the base camp integrated environmental observation system is a set of ENVIS (IMKO, Germany) which was installed at the base camp observation point by qilian station.It is stored automatically by ENVIS data mining system. 2. Data content This data set is the scale data from January 1, 2012 to December 31, 2012.Including air temperature 1.5m, humidity 1.5m, air temperature 2.5m, humidity 2.5m, soil moisture 0cm, precipitation, wind speed 1.5m, wind speed 2.5m, wind direction 1.5m, geothermal flux 5cm, total radiation, surface temperature, ground temperature 20cm, ground temperature 40cm, ground temperature 60cm, ground temperature 80cm, ground temperature 120cm, ground temperature 160cm, CO2, air pressure. 3. Space and time scope Geographical coordinates: longitude: 99° 53’e;Latitude: 38°16 'N;Height: 2980.2 m

2020-03-10

Heihe 1km FAPAR production (2000-2012)

The algorithm firstly adopts the canopy BRDF model and represents the canopy reflectivity as a function of a series of parameters such as LAI/FAPAR, wavelength, reflectivity of soil and leaves, aggregation index, incidence and observation Angle.The parameter table is established for several key parameters as the input of inversion.Then input the pre-processed surface reflectance data and land cover data, and use look-up table (LUT) inversion to obtain FAPAR products.See references for detailed algorithms. Image format: tif Image size: about 1M per scene Time range: 2000-2012 Temporal resolution: 8 days Spatial resolution: 1km

2020-03-08

LAI and FAPAR field measured datasets in Heihe Basin ( 2012 )

This data includes FAPAR and LAI data of ground sample points collected in 2012.The acquisition equipment were SunScane and lai-2000.Among them, the spread value was obtained by FAPAR measurement for 4 times.The sampling sites were located around zhangye on July 15, 2012 at solstice on July 4, 2012, including arol, linze, jiulongjiang forest farm, danoguchi and wuxing village.A total of 637 sets of data were measured.

2020-03-07

FAPAR field measured datasets in Heihe basin (2011)

This data includes the fAPAR and Lai data collected in 2011. The acquisition equipment is SunScan and LAI-2000. Among them, fAPAR measures 4 times of spread value. The sampling points are located in Zhangye agricultural demonstration base on July 30, 2011, next to national highway 312 in Ejina banner on August 4, sandaoqiao in Ejina banner on August 5 and Jiuquan Satellite Launch Center on August 6, 2011. Around Zhangye from July 4 to July 15, 2012.

2020-03-07

Data of SPAC system in the lower reaches of Heihe River (2012-2013)

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

HiWATER: Dataset of photosynthesis observed by LI-6400 in the lower of Heihe River Basin on Jul, 2012

The dataset of photosynthesis was observed by LI-6400XT Portable Photosynthesis System in the natural oasis eco-hydrology experimental area of the Heihe River Basin. Observation items included the main vegetation type in the lower reaches of Heihe river: Populus forest, which located in the Populus forest station and the mixed forest station of Ejinaqi. Observation periods lasted from 2014-07-24 to 2014-07-31. This dataset included the raw observation data of the Populus forest observed by LI-6400 during the observation periods. 1) Objectives of observation The photosynthetic datasets can be used in the study of plant physiological ecology characteristic and the simulation and validation for the eco-hydrological models. 2) Instrument and theory of the observation Measuring instrument: LI-6400XT Portable Photosynthesis System. Measuring theory: Using the infrared gas analyzer to measure the change of CO2 concentration, and then measuring the differences of CO2 concentration between the sample chamber and the referenced chamber so as to acquire the net productivity of the leaf. 3) Time and site of observation Observation site in the Populus forest station. Observation time: 2014-07-24 Observation site in the mixed forest station. Observation time: From 2014-07-25 to 2014-07-31. 4) Data processing The raw data of LI-6400 were archived in text format and can be opened by text editor or excel, the preprocessed data were in Excel format. Every time period of observation was archived in a single document, named as “date + type”.

2019-09-15

HiWATER: Dataset of photosynthesis observed by LI-6400 in the middle reaches of the Heihe River Basin

The dataset of photosynthesis was observed by LI-6400XT Portable Photosynthesis System in the artificial oasis eco-hydrology experimental area of the Heihe River Basin. Observation items included two main crops in the middle reaches of Heihe river: wheat and maize, which located in the town of Pingchuan in Linze and the Super Station of Wuxing, respectively. Observation periods lasted from mid-May to September. This dataset included the raw observation data and the pretreatment data of wheat and maize observed by LI-6400 during the observation periods. Objectives of observation: The photosynthetic datasets can be used in the study of plant physiological ecology characteristic and the simulation and validation for the eco-hydrological models. Instrument and theory of the observation: (1) Measuring instrument: LI-6400XT Portable Photosynthesis System; (2) Measuring theory: Using the infrared gas analyzer to measure the change of CO2 concentration, and then measuring the differences of CO2 concentration between the sample chamber and the referenced chamber so as to acquire the net productivity of the leaf. Time and site of observation: (1) Observation site of the wheat: in the town of Pingchuan in Linze; Observation time: 2012-05-17,2012-06-08 to 2012-6-13; (2) Observation site of the maize: in the Super Station of Wuxing; Observation time: from 2012-05-19 to 2012-08-15. The time used in this dataset is in UTC+8 Time. Data processing: The raw data of LI-6400 were archived in text format and can be opened by text editor or excel, the preprocessed data were in Excel format. Every time period of observation was archived in a single document, named as “date + type + time”, every leaf was recorded 3 times, and then added a remark.

2019-09-12