Is satellite Sun-Induced Chlorophyll Fluorescence more indicative than vegetation indices under drought condition?

Junjun Cao; Qi An; Xiang Zhang; Shan Xu; Tong Si; Dev Niyogi

doi:10.1016/j.scitotenv.2021.148396

Is satellite Sun-Induced Chlorophyll Fluorescence more indicative than vegetation indices under drought condition?

Sci Total Environ. 2021 Oct 20:792:148396. doi: 10.1016/j.scitotenv.2021.148396. Epub 2021 Jun 9.

Authors

Junjun Cao¹, Qi An², Xiang Zhang³, Shan Xu⁴, Tong Si⁵, Dev Niyogi⁶

Affiliations

¹ College of Urban and Environmental Sciences, Central China Normal University, Wuhan 430079, China; Institute of Agricultural Resources and Regional Planning, Chinese Academy of Agricultural Sciences, Beijing 100081, China; Department of Agronomy, Purdue University, West Lafayette, IN 47907, USA; Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Wuhan 430079, China.
² College of Urban and Environmental Sciences, Central China Normal University, Wuhan 430079, China; Key Laboratory for Geographical Process Analysis & Simulation of Hubei Province, Wuhan 430079, China.
³ National Engineering Research Center of Geographic Information System, China University of Geosciences (Wuhan), Wuhan 430074, China; School of Geography and Information Engineering, China University of Geosciences (Wuhan), Wuhan 430074, China. Electronic address: zhangxiang76@cug.edu.cn.
⁴ Beijing Engineering Research Center for Global Land Remote Sensing Products, Institute of Remote Sensing Science and Engineering, Faculty of Geographical Science, Beijing Normal University, Beijing 100875, China.
⁵ Shandong Provincial Key laboratory of Dryland Farming Technology, College of Agronomy, Qingdao Agricultural University, Qingdao 266109, China.
⁶ Department of Geological Sciences, Jackson School of Geosciences, University of Texas at Austin, Austin, TX 78712, USA; Department of Agronomy, Purdue University, West Lafayette, IN 47907, USA; Department of Civil, Architecture, and Environmental Engineering, University of Texas at Austin, Austin, TX 78712, USA.

PMID: 34465046
DOI: 10.1016/j.scitotenv.2021.148396

Abstract

Droughts represent one of the most severe abiotic stress factors that could result in great crop yield loss. Numerous vegetation indices have been proposed for monitoring the vegetation condition under stress and assessing drought impacts on yield loss. However, the understanding and comparison between traditional vegetation indices (VIs) and the newly emerging satellite Sun-Induced Chlorophyll Fluorescence (SIF) for monitoring vegetation condition is still limited especially under drought stress and at multiple spatial scales. In this study, the potential of satellite observation SIF for monitoring corn response to drought was investigated based on the 2012 drought in the US Corn Belt. The standardized precipitation evapotranspiration index (SPEI) was used here to quantify drought. We found that all SPEI were above -1, except for July (-1.27), August (-1.39) and September (-1.14) in 2012, indicating the severity of this drought. We examined the relationship between satellite measurements of SIF, SIF_yield, VIs (e.g., NDVI and EVI) and SPEI. Results indicated that SIF_yield was sensitive to drought and SIF captured the stress more accurately both at the regional and state scales for the US Corn Belt. Quantitatively, SIF_yield had a high correlation with SPEI (r = 0.987, p < 0.05) over the entire Corn Belt, and it indicated losses in response to drought approximately one month earlier than SIF/NDVI/EVI. Furthermore, our results demonstrated that SIF could be trusted as an effective indicator to study the relationship between GPP (R² ≥ 0.8664, p < 0.01) under drought conditions across the Corn Belt. This study highlighted the advantage of using satellite SIF observations to monitor the drought stress on crop growth especially GPP at regional scale.

Keywords: Drought; Gross primary production; Solar-induced chlorophyll fluorescence; US Corn Belt; Vegetation indices.

MeSH terms

Chlorophyll*
Droughts*
Fluorescence
Seasons
Zea mays

Substances

Chlorophyll