Abstract:

Hainan conserves one of the last tropical rainforests in China. The space-air-ground comprehensive data in tropical forest is not only the basis of the management of National Park of Hainan Tropical Rainforest,but also an important component to set up methodology of Terrestrial Ecosystem Carbon Inventory Satellite (TECISat) in China. From March 20,2020 to July 10,2021,we used National Forest and Grassland Inventory (NFGI) airborne platform to produce 20TB raw data and products that covered an area more than 6000 km²,including airborne large-footprint LiDAR,small-footprint LiDAR,visible and near-infrared image,and ultra-spectrum image. We also collected data from 170 forest plots,183 ground control points and 17 checking polygons. Combined with GF-7 and GEDI data,these data constituted the space-air-ground data covering National Park of Hainan Tropical Rainforest and surrounding area. The products showed that the horizontal and elevation accuracy of large-footprint LiDAR were better than 1m and 0.15m respectively. The horizontal and elevation accuracy of small-footprint LiDAR were better than 0.5m and 0.08m respectively. The elevation accuracy of DEM and height precision of CHM were 0.15m and 91.8% respectively. The horizontal accuracy of 0.2m DOM was better than 0.5m. The spectral and spatial resolution of ultra-spectrum image were 0.24nm and 1~2m respectively. This experiment provided high quality products and space-air-ground data for TECISat and national park management.

Key words: National Forest and Grassland Inventory (NFGI) airborne platform, NFGI airborne Large-footprint LiDAR (NFGI-LIDAR-L), NFGI Small-footprint LiDAR (NFGI-LIDAR-S), NFGI airborne Ultra-spectrum camera (NFGI-SPECTRUM-U), Digital Elevation Model (DEM), Canopy Height Model (CHM), Digital Orthophoto Map (DOM), Terrestrial Ecosystem Carbon Inventory Satellite