The basic data set of remote sensing for ecological assets assessment of the Qinghai-Tibet Plateau includes the annual Fraction Vegetation Coverage (FVC), Net Primary Productivity (NPP) and Leaf Area Index (LAI) of the Qinghai-Tibet Plateau since 2000, and other ecological parameters based on remote sensing inversion. The improved LAI estimation method based on TSF filter and scale down method are used to improve the LAI data.
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.
The dataset is Lai data of ground sample points in Heihe River Basin, collected by LAI-2000 canopy analyzer. The collection area is located in Zhangye rural demonstration base, Ejina Banner, Jiuquan Satellite Center (2011) and other areas. The main measured vegetation is corn. The Lai value of maize was obtained by using lai2000, and the observation was repeated twice in the mode of one up four down. Cd202 was used to obtain the leaf area of each leaf of maize plant, and three maize plants were collected.
Leaf area index, also known as leaf area coefficient, refers to the multiple of the total area of plant leaves in the land area per unit land area. Leaf area index is an important structural parameter of ecosystem, which is used to reflect the number of plant leaves, the change of canopy structure, the life activity of plant community and its environmental effect, to provide structured quantitative information for the description of material and energy exchange on the canopy surface, and to balance the energy of carbon accumulation, vegetation productivity and the interaction between soil, plant and atmosphere, Vegetation remote sensing plays an important role. Plant canopy imager CI - 110 was used to measure the alpine shrub and spruce leaf area index in hulugou watershed. The measurement period is July 22, 2014. It includes the main shrub types and Picea crassifolia forest in hulugou watershed. The data set mainly includes the original data of CI-110 measurement, including image and leaf area analysis image.
The forest hydrology experimental area of Heihe River integrated remote sensing experiment includes the dense observation area of Dayekou basin and the dense observation area of Pailugou basin. Due to the concentrated distribution of the fixed sample plots in the drainage ditch basin, these sample plots lack of representativeness to the forest of the whole dayokou basin, so in June 2008, 43 temporary forest sample plots were set up in the whole dayokou basin. The data set is the ground observation data of the 43 temporary plots. In addition to the measurement and recording of stand status and site factors, Lai was also observed. The instruments used to measure each wood in the sample plot are mainly tape, DBH, flower pole, tree measuring instrument and compass. The DBH, tree height, height under branch, crown width in cross slope direction, crown width along slope direction and single tree growth were measured for each tree. WGS84 latitude and longitude coordinates of the center point of the sample plot were measured with different hand-held GPS, and the positioning error was about 5-30m. Other observation factors include: Forest Farm, slope direction, slope position, slope, soil thickness, canopy density, etc. The implementation time of these temporary sample plots is from 2 to 30 June 2008. The supplementary measurement time of Lai is from August 24 to September 2, 2008. The instruments used in the measurement are hemiveiw fisheye camera and LAI-2000 canopy analyzer. The two instruments measure at the same time. It should be noted that only one LAI-2000 canopy analyzer is used for this measurement. During the survey, 5 points are measured for each sample plot, which are respectively the center points, namely, due north, East, South and West. The Lai of the plot is the mean of 5 points. The data set can provide ground data for the development of remote sensing inversion algorithm of forest structure parameters.
On August 6, 2004, the institute of cold and drought, Chinese academy of sciences, organized a remote sensing experiment in the upper reaches of the heihe river basin, which obtained soil survey data of 14 sections, DEM of 1:500 scale in the drainage ditch basin, spectral data of typical features and synchronous ground observation data of dapingding TM and QuickBird satellite.It mainly includes: 1) spectral measurement data of typical ground objects The data mainly includes in continental river basin in linze county comprehensive research station near the station (hereinafter referred to as linze) of elaeagnus angustifolia, two poplars, tamarisk, bark, ephedra, sand, alfalfa, corn, cotton and salinization land spectra and dew ditch valley concept-people mei, grass, moss, alpine meadow grass, sword leaf thorns son, the spectra of soil and rock. 2) soil profile survey data Valley in line according to the altitude and vegetation types were set up 12 soil profile, and also in front of the row of dew ditch forest weather stations and linze weather station set up a soil profile 1, 14 were measured profile of soil moisture content, bulk density, adhering sand content and soil spectrum, dew ditch forest top weather stations and linze profile is measuring the thermal conductivity of soil and water parameters. 3) field measurement data of biophysical parameters of typical ground objects Standing near the corn, cotton, including linze small pine, alfalfa, and leaf area index measurement data of ephedra row dew in different heights with leaf photosynthesis, leaf area index data and vegetation features data (photosynthetic rate, stomatal conductance, intercellular CO2 concentration, leaf transpiration rate, leaf temperature) and the corresponding environmental factor data (air temperature, air relative humidity and atmospheric CO2 concentration, air, water content, atmospheric pressure, solar total radiation, photosynthetic active radiation). 4) ground synchronization test of remote sensing by large flat-topped satellite The simultaneous observation experiment of TM and QuickBird satellite was carried out in a relatively flat grass area (big flat roof) beside the drainage ditch watershed.On July 27, 2004, spectra, above-ground biomass and leaf area were measured at intervals of 15 meters in a 150m×150m quadrangular at a large flat roof.
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 invert LAI products by look-up table (LUT) method.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
From May to October 2012, the monthly Lai vegetation index product data of 30 meters in Heihe River Basin was retrieved by using the environmental satellite CCD image, and the inversion method was based on the look-up table method and go + Hapke model. In the inversion process, Nelson parameters are determined according to vegetation types.
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.