Department
Biology
Document Type
Article
Publication Date
2023
Abstract
Climate change has significantly impacted vegetation phenology across the globe. The general consensus is that the Earth’s vegetation has experienced an advance in the spring phases and a delay in senescence. However, some studies from high latitudes and high elevations have instead shown delayed spring phenology, owing to a lack of chilling fulfillment and altered snow cover and photoperiods. We have used the MODIS satellite-derived view-angle corrected surface reflectance data (MCD43A4) to document the four phenological phases in the high elevations of the Sikkim Himalaya, and compared the phenological trends between below-treeline zones and above-treeline zones. This analysis of remotely sensed data for the study period (2001-2017) reveals considerable shifts in the phenology in the Sikkim Himalaya. Advances in spring phases (SOS) were more pronounced than delays in the dates for maturity (MAT), senescence (EOS), and advanced dormancy (DOR). The SOS significantly advanced by 21.3 days while the MAT and EOS were delayed by 15.7 days and 6.5 days respectively over the 17-year study period. The DOR showed an advance of 8.2 days over the study period. The region below the treeline showed more pronounced effects in phenology with respect to an advanced SOS and a delayed EOS and DOR. The MAT, however, showed a greater delay in the zone above the treeline than below. Lastly, there is no indication that winter chilling requirements are driving the spring phenology in this region, unlike other studies from high elevations. We discuss four possible explanations why vegetation phenology in the high elevations of the Eastern Himalaya may exhibit trends independent of chilling requirements and soil moisture due to mediation by snow cover.
Recommended Citation
Ingty, T., Erb, A., Zhang, X., Schaaf, C., & Bawa, K. S. (2023). Climate change is leading to rapid shifts in seasonality in the Himalaya. International Journal of Biometeorology, 67(5), 913-925. https://doi.org/10.1007/s00484-023-02465-9
Publication/Presentation Information
International Journal of Biometeorology, 67(5), 2023, 913-925.