Authors: Yilun Zhao*, Department of Geography and Geographic Information Science, University of Illinois at Urbana-Champain, Chunyuan Diao, Department of Geography and Geographic Information Science, University of Illinois at Urbana-Champaign
Topics: Remote Sensing, Environment
Keywords: Leaf phenology, multi-scale remote sensing, PlanetScope
Session Type: Virtual Paper
Start / End Time: 8:00 AM / 10:20 AM
Room: Virtual 29
Presentation File: No File Uploaded
Leaf phenology is an important climate change indicator of terrestrial ecosystems. The phenology of individuals affects the spatial variation of the community phenology. In temperate forests, many studies have observed a high variation in fall phenology than in spring. Therefore, it is important to monitor temperate forest phenology at both community and individual scales. However, lacking high spatial and temporal resolution information and the difference between information from different data sources challenge study phenology at the community and individual scales. The high spatial and near-daily PlanetScope constellation provides a great opportunity to monitor leaf phenology. In this study, we observed the community and individual phenology of a temperate forest in Champaign Illinois with data from multiple satellites. The community time series NDVI and EVI2 from 2016 to 2019 were extracted from MODIS satellites, Landsat 8, Harmonized Landsat Sentinel-2, and PlanetScope surface reflectance products. The spring and fall phenophases were extracted from the time series VIs and compared to field community leafiness, greenness, and tree spring and fall stages. The individual time series VIs were extracted from PlanetScope products. The phenophases extracted from individual time series were compared with field information of the corresponding crowns. The phenophases of different species were compared to understand their effect on forest community phenology. The results show that the fall community phenology is affected mostly by species differences. This study demonstrates the potential of HLS data on monitoring community leaf phenology and the potential of PlanetScope data on monitoring individual leaf phenology.