Fig. 2
From: Developing drought stress index for monitoring Pinus densiflora diebacks in Korea
Spatial distributions. a DSI during 2001–2016. b SPI6, HI6, and DSI in 2009. c SPI6, HI6, and DSI in 2014. A diagonal stripe in (a) indicates the area where the Pinus densiflora group dieback occurred. The DSI map in (b) and (c) have different scales. DSI Drought Stress Index, HI6 heat index based on six months’ periodicity, SPI6 Standardized Precipitation Index based on six months