Mangroves under threat; Indian coastline could see certain species shifting landward
A study predicts that certain species of mangroves could reduce and shift towards the land by year 2070.
Decline in suitable habitats in response to precipitation and sea level changes is seen as pushing back certain mangrove species landward in the eastern and western coat of India. A study, that bases itself on a prediction model, has stated that there are chances of certain species of mangroves in Chilika and Sundarbans along the east coast of the country to reduce and shift towards the land by year 2070.
Meanwhile, along the west coast, the Dwarka and Porbandar coasts could encounter a similar phenomenon buy the year that has been predicted. The significance of this study is that it could pave the way towards identifying highly suitable areas for conservation and management and develop conservation strategies for the future.
Mangroves help reduce coastal ecological risks
It is an accepted fact that mangroves are essential in the conservation of the ecosystem. They also help reduce coastal ecological risks. However, the sad truth is that they are also among the most severely endangered ecosystems. Mangroves have been rapidly declining due to climate change, sea level fluctuations, and human activities.
According to a statement from the Science and Technology ministry, limited understanding of mangrove spatial distribution and species habitat requirement have reduced the success of conservation initiatives in many areas along the Indian coastline. This underlines an urgent need to develop model-based studies to identify conservation target areas at Spatio-temporal scales, specifically in rich mangrove biodiversity regions along the Indian coastline, it said.
Scientists at the BSIP, an autonomous institution of the Department of Science and Technology (DST), used ensemble species distribution model to study the past and current state of two mangrove species and predict their future. They found significant reduction and landward shift of mangroves in the future (2070) due to decline in suitable habitats, specifically along the east and west coast of India in response to precipitation and sea level changes in the future. In contrast, the maximum range expansion of the mangroves was mapped in the past, which was validated by fossil pollen data.
The findings are projected as useful in the implementation of mitigation and adaptation strategies in the identified hotspots for conserving the coastal wetlands and reducing the impact of climate change on the coastal vegetation along the Indian coastline.
Coast vulnerable to the impact of climate, sea-level changes
The coastal regions of the country are vulnerable to the impact of climate and sea level changes, and there is not much attempt for the coastal wetland species prediction and management, with limited research carried out for their future habitat mapping. To fill this gap, this study tried to project the potential impact of climate change on mangroves as coastal wetland species.
A team of scientists including Pujarini Samal, Jyoti Srivastava, Pooja Nitin Saraf, Bipin Charles, and Singarasubramanian SR collected species location points and extracted environmental data from Worldclim database. They combined the climate variables and species present occurrence points in the model to predict the potential distribution and habitat suitability of the species both over time and over the area under novel climatic conditions.
Calculating the trend of suitable area change along the Indian coastline in the past, present, and future climate change scenarios, they estimated the total area of the suitable habitat for current, past, and future scenarios in km2 for the mangrove species.
The study has been published in the Ecological Informatics journal. The estimations could prove to be a valuable resource for the conservation of coastal wetlands across India by mapping the suitable habitats of the key mangrove species in India. The study also suggests that establishing effective buffer zones in these conserved areas can narrow down the effect of non-conservative areas on the core conservative zone, and adopting preventive measures can turn some areas into highly suitable regions for facilitating the growth of these mangrove species.