title: Assessing plant senescence reflectance index-retrieved vegetation phenology and its spatiotemporal response to climate change in the Inner Mongolian Grassland.
abstract: Plant phenology is a key link for controlling interactions between climate change and biogeochemical cycles. Satellite-derived normalized difference vegetation index (NDVI) has been extensively used to detect plant phenology at regional scales. Here, we introduced a new vegetation index, plant senescence reflectance index (PSRI), and determined PSRI-derived start (SOS) and end (EOS) dates of the growing season using Moderate Resolution Imaging Spectroradiometer data from 2000 to 2011 in the Inner Mongolian Grassland. Then, we validated the reliability of PSRI-derived SOS and EOS dates using NDVI-derived SOS and EOS dates. Moreover, we conducted temporal and spatial correlation analyses between PSRI-derived SOS/EOS date and climatic factors and revealed spatiotemporal patterns of PSRI-derived SOS and EOS dates across the entire research region at pixel scales. Results show that PSRI has similar performance with NDVI in extracting SOS and EOS dates in the Inner Mongolian Grassland. Precipitation regime is the key climate driver of interannual variation of grassland phenology, while temperature and precipitation regimes are the crucial controlling factors of spatial differentiation of grassland phenology. Thus, PSRI-derived vegetation phenology can effectively reflect land surface vegetation dynamics and its response to climate change. Moreover, a significant linear trend of PSRI-derived SOS and EOS dates was detected only at small portions of pixels, which is consistent with that of greenup and brownoff dates of herbaceous plant species in the Inner Mongolian Grassland. Overall, PSRI is a useful and robust metric in addition to NDVI for monitoring land surface grassland phenology.
authors: College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, 5 Yiheyuan Road, Yifuerlou Room 3352, Beijing, 100871, People's Republic of China.
authors: Shilong
authors: S
authors: Ren
authors: College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, 5 Yiheyuan Road, Yifuerlou Room 3352, Beijing, 100871, People's Republic of China. cxq@pku.edu.cn.
authors: Xiaoqiu
authors: X
authors: Chen
authors: College of Urban and Environmental Sciences, Laboratory for Earth Surface Processes of the Ministry of Education, Peking University, 5 Yiheyuan Road, Yifuerlou Room 3352, Beijing, 100871, People's Republic of China.
authors: Shuai
authors: S
authors: An
mesh_terms: D002681:China; D057231:Climate Change; D065948:Grassland; D063245:Plant Development; D063809:Satellite Imagery; D012621:Seasons; D013696:Temperature
keywords: Grassland phenology; Plant senescence reflectance index; Remote sensing; Spatiotemporal pattern; Spatiotemporal response; Temperature and precipitation