Event-consequence chain of climate change-induced salinity intrusion in Sundarbans mangrove socioecological system, Bangladesh

The Sundarbans is an active biogenic coast entitled to world heritage site. The most notable feature of this Sundarbans is that it is located in a sea-influenced region but depends on nutrient-enriched freshwater flow from the upstream rivers. With its intrinsic transboundary ecological functions, the Sundarbans also provides buffer for lives and livelihood opportunity for millions of people living in its immediate vicinity. Woodcutter, honey collector, fisher, fuel wood collector, and snail and oyster collector are the major livelihood groups directly depending on Sundarbans. Society-ecosystem interrelationship and dependence on hydromorphologic system make this deltaic mangrove a unique socioecological system and also very vulnerable to climate change-induced salinity intrusion. Mangrove ecosystem health with its productivity is deteriorating due to climate change-induced rising salinity in major rivers of the Sundarbans. This change in ecological productivity ultimately affects the forest-dependent livelihoods. This chapter presents an analysis of evolving nature of salinity intrusion hazard developing in the mangrove socioecological system. The evolving nature of salinity intrusion was analyzed through developing Event-Consequence Chain for each of the five livelihood capitals (Natural, Financial, Physical, Human, and Social) of a Sundarbans-dependent livelihood group. Besides, the control options were identified with the aim of unplugging the pathways between two successive events (or sequential consequences) or of lingering the evolving nature. The overall study was carried out through participatory approach using Shared Learning Dialogue method to ensure engagement of the local community. This research discusses the sequential events evolving with salinity intrusion from hydrologic system to its reach-the livelihood system. At the end, it presents an indicative adaptive strategy developed based on identified control stages of the hazard chains for climate change resilient governance of the mangrove socioecological system that clearly calls for delta-based approach of management.