The file includes both field measured and satellite derived high resolution LAI data obtained over the Honghe farm and Hailun site in northeastern China.
The Honghe farm (centered at 47°39′N, 133°31′E) is located in the east of the Heilongjiang province, northeast China. Five plots in 400 m × 600 m were selected in the Honghe farm in 2012 and 2013. Within each plot, about 50 - 60 elementary sampling units (ESUs) about 20 m ×20 m in size were selected in different weeks with a moving sampling strategy to avoid the sampling disturbance. Field LAI measurements were performed weekly from June 11 to September 17, 2012, and from June 22 to August 27, 2013. All ESU measurements made with LAI-2200 within a plot were averaged to represent the plot LAI.
The Hailun site (47°24′- 47°26′N, 126°47′- 126°51′E) is located in the western part of the Heilongjiang province. The main crop types are maize, soybean, and sorghum. Five crop plots in 100 m × 500 m were chosen for continuous LAI measurements. The plots cover an areas of about 30 km2 and an elevation of approximately 200-240 m above sea level with quite homogeneous surroundings. Three representative ESUs of approximately 20 m × 20 m were selected in each plot. Field LAI measurements were continuously carried out with LAI-2200 weekly at each plot from June 20 to September 22, 2016.
The high-resolution LAI data were estimated with a look-up table (LUT) method from the HJ-1, Landsat 7 ETM+, and Sentinel-2A MSI reflectance data. The high resolution LAI data are consistent with the field measured LAI characterized by a slope close to the 1:1 line. The statistical results show R2 of 0.81 and 0.86, and RMSE of 0.62 and 0.70 for paddy rice and broadleaf crops, respectively. The scale factor is 0.01.
