Shifts in Growing Season of Tropical Deciduous Forests as Driven by El Nino and La Nina during 2001-2016

This study investigated the spatiotemporal dynamics of tropical deciduous forest including dry dipterocarp forest (DDF) and mixed deciduous forest (MDF) and its phenological changes in responses to El Nino and La Nina during 2001-2016. Based on time series of Normalized Difference Vegetation Index (NDVI) extracted from Moderate Resolution Imaging Spectroradiometer (MODIS), the start of growing season (SOS), the end of growing season (EOS), and length of growing season (LOS) were derived. In absence of climatic fluctuation, the SOS of DDF commonly started on 106 +/- 7 DOY, delayed to 132 DOY in El Nino year (2010) and advanced to 87 DOY in La Nina year (2011). Thus, there was a delay of about 19 to 33 days in El Nino and an earlier onset of about 13 to 27 days in La Nina year. The SOS of MDF started almost same time as of DDF on the 107 +/- 7 DOY during the neutral years and delayed to 127 DOY during El Nino, advanced to 92 DOY in La Nina year. The SOS of MDF was delayed by about 12 to 28 days in El Nino and was earlier about 8 to 22 days in La Nina. Corresponding to these shifts in SOS and LOS of both DDF and MDF were also induced by the El Nino-Southern Oscillation (ENSO).