This data includes spectral reflectance and BRDF data sets measured in Yingke oasis and huazhaizi desert intensive observation area. Data measurement began on May 20, 2008.

  Measuring instrument and principle: ASD (analytical Sepctral devices) spectrometer was used to measure the reflectivity of Yingke oasis and huazhaizi desert intensive observation area and typical features in the observation area. 1. Basic principle of measurement: r = (DN1 / dn0) × R0。 Where R0 and dn0 are the calibrated spectral reflectance of the reference reflective gray plate and the measured DN value respectively; DN1 is the DN value obtained from the measurement target.

  Survey content: survey sample plots and data types: Yingke oasis corn plot, Yingke wheat plot, huazhaizi desert corn plot, huazhaizi desert sample plot 1, huazhaizi desert sample plot 2, Linze grassland intensive observation area, biandukou intensive observation area, etc. Among them, the main measuring points of corn field in Yingke oasis are corn canopy spectrum, wheat canopy spectrum, strip spectrum and several times of corn leaf component spectrum. BRDF of corn field was measured many times in this sample plot. Huazhaizi desert sample 1 and huazhaizi desert sample 2 mostly adopt strip measurement, and there is no real component spectrum. Yingke wheat field and huazhaizi desert corn field and other experimental areas are also mostly canopy and band spectra.

 & emsp; Measuring instruments: there are four ASD spectrometers before and after Yingke oasis and huazhaizi desert, i.e. one for Peking University, Institute of remote sensing application, Chinese Academy of Sciences, Beijing Academy of agricultural and Forestry Sciences and Beijing Normal University. The ASD spectrometer of Peking University and Institute of remote sensing applications, Chinese Academy of Sciences, with a wavelength of 350-2500 nm, is the main measuring instrument; The ASD wavelength of Beijing Academy of agricultural and Forestry Sciences is 350-1065nm. In the early stage of the experiment, it is used for satellite or flight synchronous spectrum measurement in desert samples. The ASD spectrometer of Beijing Normal University only measured the spectral data of huazhaizi desert sample 2 on May 20, 2008. The reference reflectance plates are 40%, 50% and 99%. The first two are the actual measurement reference objects, and the latter is mainly used for mutual comparison between instruments.

  Measurement date: 2008-05-202008-05-242008-05-252008-05-282008-05-302008-06-012008-06-042008-06-092008-06-142008-06-162008-06-182008-06-202008-06-222008-06-232008-06-242008-06-262008-06-292008-06-302008-07-012008-07-042008-07-052008-07-062008-07-072008-07-09, 2008-07-11。 July 11, 2008 is the comparison test between spectrometers, in which the following dates are measured by two instruments of Peking University and Institute of remote sensing application, Chinese Academy of Sciences: May 28, 2008, June 16, 2008, June 23, 2008; The measured data are matched with airborne infrared wide-angle dual-mode imager widas (wide angle infrared dual-mode line / area array scanner) aviation flight, imaging spectrometer omis-ii aviation flight and a variety of spaceborne sensors.

  Data processing: including original data, recorded data and processed reflectance data. The original data is in the standard format of ASD spectrometer, which can be opened by its own software viewspec. This sub data set has been exported to excel format. The processed reflectance data is saved in Excel format.