About 40 percent of the nearly 10,000 square kilometers (km²) of the Sundarbans forest lies within West Bengal; the rest is in Bangladesh.

Mangrove litter decomposition in Sundarban ecosystems: study by ICAR-CIFRI

Looking into the importance of mangrove leaf litter in regulation of sediment carbon sequestration and nutrient flux in Sundarbans ecosystem, a project was undertaken by ICAR-CIFRI at Jharkhali island of Sundarbans for determining the decomposition of different mangrove leaf litter. Seasonal litter fall was highest in Geon (Excoecaria agallocha). Litter from Avicennia group contained more nitrogen and carbon. Decomposition rates of various mangrove litters were estimated through in-situ litter-bag experiments using mangrove leaf litter and during decomposition process, observation said that most susceptible and resistant litter with respect to mass loss were Geon (Excoecariaagallocha) and Taura (Aegialitis rotundifolia), respectively. The study gives important insight into contribution of different mangrove species in carbon sequestration and nutrient dynamics in mangrove ecosystem of Indian Sundarbans.

Assessment of environmental variability, nutrient dynamics, biodiversity, fish stock in mangrove ecosystems of Sundarban: Research by ICAR-CIFRI

Fish distribution and assemblage pattern in relation to environmental variables were studied in the selected stretches (Jharkhali, Sandeshkhali, Pathar Pratima, Frazerganj and Nischintapur) of Indian Sundarbans  Estimation of fish landings from winter bag net fisheries  along the lower Sundarbans revealed a major shift in the fish catch composition with  dominance of trash fishes and sardines. Harpadon nehereus, a dominant species in winter bag net fishery, showed a reduction from 18.34 % (1362.92 tonnes) in 2009- 10 to 12.33 % in 2015-16 (1475.29 tonnes). Sartoriana spinigera was the only  freshwater crab found from selected stretches of Sundarbans.  A total of 84 finfish and shellfish species belonging to 38. The phytoplankton profile and their spatio-temporal dynamics at various geographical locations of the Sundarban eco-region stands unique in providing a comprehensive information on the status of the ecological interaction with certain phytoplankton groups impacted due to gradual increase of anthropogenic load. Water quality parameters, such as temperature, TA, salinity, PO4−P, SiO4−Si and SO42- were found to have deterministic influence on the distribution, abundance and diversity of phytoplankton in Indian Sundarbans.

Activities/ technological interventions of ICAR-Central Inland Fisheries Research Institute, Barrackpore on the ‘Exploration of canal resources as a potential source for fish production in the Indian Sundarbans’

Indian Sundarbans are rich in canal systems, and natural forms of these resources were excavated for freshwater resources. Large number of canals in Indian Sundarbans are tide fed through the connecting channels. These canals are the source of livelihood and household nutrition for the local populace. Yet, these resources are underutilized in terms of sustainable fish production. Hence, ICAR-Central Inland Fisheries Research Institute has taken initiative for the canal fisheries development by a degree of management and technological interventions in different canals of Sundarbans. The ecological status of the selected canals (Bhetkimari, Bishalakhi, Bharua) has been studied to assess the fish production potential and productivity. Keeping view of the scientific utilization of these resources in fisheries perspectives, ICAR-CIFRI initiated the ‘net partition systems’ for carp polyculture’ in selected canals (Bishalakhi and Bharua canal), where the stocked Indian Major Carps were resulting good growth. It was practiced with a participatory mode with the local fish farmers living around the canal, where a group were formed for their support to carry out the culture activities during the experiment.  The technology built the capacity and motivated fishers to take up underutilized canal fish culture and enhanced their employment and income.