Rivers form the backbone of aquatic ecosystems, functioning as dynamic and life-supporting systems that influence biodiversity, ecological balance, and human societies. A river ecosystem is not only a flowing body of water but also the surrounding habitats, vegetation, organisms, and communities that directly or indirectly depend on its resources. At the local level, especially in rural and semi-urban settings, rivers have historically been crucial in ensuring livelihood security by providing water, food, energy, transportation, cultural value, and ecological services. The interrelationship between rivers and human livelihoods represents a deep bond where survival, traditions, and sustainable development are interwoven with aquatic systems. The primary significance of the river ecosystem for livelihood security emerges from its role in water supply. Freshwater from rivers is indispensable for drinking, sanitation, irrigation, and small-scale domestic uses. Local communities depend on rivers for consistent and accessible water, which forms the foundation of health, agricultural productivity, and daily sustenance. Unlike groundwater reserves that require drilling or expensive infrastructure, rivers offer surface water that is more readily accessible to marginalized groups. In many parts of the world, local economies would collapse without the perennial flow of river water, particularly in regions where rainfall is seasonal and erratic. A second dimension of livelihood security supported by river ecosystems is agriculture. Rivers sustain fertile floodplains, recharge soil nutrients, and enable irrigation for crops. Traditional farming systems such as flood recession agriculture and riverbank cultivation have flourished along river valleys for centuries. These practices not only provide food security but also generate income for smallholder farmers. Seasonal floods deposit nutrient-rich silt that replenishes soil fertility, reducing the need for chemical fertilizers and sustaining sustainable agriculture. Villages situated near rivers often diversify crops such as rice, wheat, pulses, and vegetables due to the assurance of water availability. Thus, river ecosystems create a resilient agricultural base at the local level. Beyond agriculture, fisheries form one of the most direct livelihood sources linked to river ecosystems. Freshwater fish populations, ranging from small indigenous species to commercially valuable varieties, provide protein and income to millions of people worldwide. Fishing communities rely on rivers not only for sustenance but also for trade in local markets. The breeding grounds, wetlands, and aquatic vegetation associated with rivers create habitats that sustain fish diversity. Moreover, fish culture practices such as cage culture and pond fisheries are often supported by river systems, enhancing local economies and providing employment. For landless households, fishing serves as an accessible livelihood option that requires relatively little capital input compared to farming or industry. Livelihood security derived from river ecosystems also extends to non-timber resources such as reeds, medicinal plants, and aquatic vegetation. Communities utilize these resources for making mats, ropes, medicines, and handicrafts. Wetland plants along riversides are harvested for fodder to sustain livestock, which further