Using spectral indices as early warning signals of forest dieback: The case of drought-prone Pinus pinaster forests

• DOI: 10.1016/j.scitotenv.2021.148578
• Publication Date: 2021-06-19T04:37:04Z
• Authors: Daniel Moreno-Fer...; Alba Viana-Soto; Julio Jesús Camarero; Miguel A. Zavala; Julián Tijerín; Mariano García
• Keywords: Pinus pinaster

Forest dieback processes linked to drought are expected increase due climate warming. Remotely sensed data offer several advantages over common field monitoring methods such as the ability observe large areas on a systematic basis and their changes, making them increasingly used assess changes in forest health. Here we aim use combined approximation of fieldwork remote sensing explore possible links between land surface phenological trend variables derived from long Landsat time series. was evaluated 31 plots Mediterranean, xeric Pinus pinaster forest. 31-year series three greenness (EVI, NDVI, SAVI) two wetness spectral indices (NMDI TCW) were covering period 1990–2020. Spectral decomposed into seasonality using Bayesian estimator while relationships among levels damage assessed linear additive mixed models. We have not found any statistical pieces evidence extension or shortening patterns for length season examined period. Our results indicate that process mainly related component whereas metrics dieback. also with more dying damaged trees displayed lower trends after severe event middle 1990s, which confirms Landsat-derived indicators early-warning signals. Drops occurred earlier rather than suggests former could be appropriate detection, i.e. they early warning signals impending loss tree vigor.