Disentangling remotely-sensed plant phenology and snow seasonality at northern Europe using MODIS and the plant phenology index

REMOTE SENSING OF ENVIRONMENT

卷:198

Article

Jin, Hongxiao¹  Jonsson, Anna Maria¹  Bolmgren, Kjell²  Langvall, Ola³  Eklundh, Lars¹ 

[1] Lund Univ, Dept Phys Geog & Ecosyst Sci, SE-22362 Lund, Sweden

[2] Swedish Univ Agr Sci, Swedish Natl Phenol Network, SE-36030 Lammhult, Sweden

[3] Swedish Univ Agr Sci, Unit Field Based Forest Res, S-92291 Vindeln, Sweden

关键词: MODIS;    NDVI;    Plant phenology index (PPI);    Land surface phenology;    Snow seasonality;   

DOI  :  10.1016/j.rse.2017.06.015

来源: Elsevier

【 摘 要 】

Land surface phenology is frequently derived from remotely sensed data. However, over regions with seasonal snow cover, remotely-sensed land surface phenology may be dominated by snow seasonality, rather than showing true plant phenology. Overlooking snow influences may lead to inaccurate plant phenology estimation, and consequently to misinterpretation of climate-vegetation interactions. To address the problem we apply the recently developed plant phenology index (PPI) to Moderate Resolution Imaging Spectroradiometer (MODIS) data for estimating plant phenology metrics over northern Europe. We compare PPI-derived start and end of the growing season with ground observations by professionals (6 sites) and nonprofessional citizens (378 sites), with phenology metrics derived from gross primary productivity (GPP, 18 sites), and with data on the timing of snow cover. These data are also compared with land surface phenology metrics derived from the normalized difference vegetation index (NDVI) using the same MODIS data. We find that the PPI-retrieved plant phenology agrees with ground observations and GPP-derived phenology, and that the NDVI-derived phenology to a large extent agrees with the end-of-snowmelt for the start-of-season and the start-of-snowing for the end of-season. PPI is thereby useful for more accurate estimation of plant phenology from remotely sensed data over northern Europe and other regions with seasonal snow cover. (C) 2017 Elsevier Inc All rights reserved.

【 授权许可】

Free