Research Projects

The 2022 Bali G20 JECMM has re-emphasized the critical role of coastal ecosystems and pointed out that coastal wetlands are increasingly witnessing climate change driven sea level rise, unprecedented warming, hyper-salinity, ocean acidification and inundation. Mangroves are the dominant wetland vegetations along tropical and subtropical coasts that grow year-round contributing to a significant percentage of the primary productivity on tropical coasts. There is little or no information on mangroves’ ecophysiological processes including thermoregulation, thermotolerance and photoprotection performance. These functional traits interact with coastal climate, affect species photosynthetic carbon gain, and contribute to net primary and ecosystem productions. We don’t know to what extent co-existing mangrove species differ in these functional traits, how dynamic are these traits, and whether they could help to acclimate and adapt under climate change. Through our proposed project, we aim to investigate species-level differences in mangroves’ functional traits, the acclimation or adaptation likelihood of different species to environmental perturbations and identify which ecophysiological traits or processes could act as key predictive tools for resiliency under extreme events. We propose to calibrate and validate a model for scaling-up mangrove dynamic physiological responses using hyperspectral sensing. For field surveys and experiments, we have proposed three strategic locations including two in the southwest (Azheekal and Puthuvype mangrove forests in Kerala) and one in the southeast coast (Pichavaram forest in Tamil Nadu) of India. Different traits associated with thermoregulation, thermotolerance, photosynthetic efficiency and photoprotection will be measured using thermal camera and pulse modulated chlorophyll fluorometers. Survey-based point measurements, and diurnal and seasonal measurements will be conducted paired with hyperspectral sensing. To identify species-level thresholds for mechanistic damage to key physiological processes during climatic extremes (like heat waves and hyper-salinity), short-term mesocosm experiments have been proposed on potted mangrove plants. We will develop a multistep analytical and predictive framework combining the hyperspectral data, considering the variations in leaf water and pigment contents, and different chlorophyll fluorescence parameters. This integrative approach with contextual information (meteorological variables and species identity) could be useful as an early pre-visual stress indicator. Overall, our proposed research will lead to an improved understanding of the relationships between short-term ecophysiological responses and long-term stand dynamics in mangroves. Our proposed project will identify and provide a reliable and effective ecophysiological framework for quantifying the resilience of Indian mangrove forests to environmental perturbations.