Developed river deltas: are they sustainable?

Abstract

Background . Coastal river deltas provide multiple ecosystem services. Many deltas serve as major centers of agriculture, industry and commerce. The annual economic benefits derived from major deltas are often a substantial fraction of a country’s GDP. Yet, many deltas are losing land due to erosion, subsidence and subsequent flooding. Such vulnerabilities are often increased due to local land and water management decisions, relative sea-level rise, and increases in climate extremes. Aim of this review . Considerable literature exists addressing the formation of deltas and the effects of increasing urbanization, industrialization and crop and fish production, increases in relative sea level rise, and decreasing sediment deposition. This leads to the question: are the economic, environmental, ecological and social benefits derived from developed river deltas sustainable? This review focuses on this question. Methods/Design. Over 180 published documents were identified and reviewed using various search engines and key words. These key words included river deltas; delta sustainability, vulnerability, resilience, coasts, ecology, hazards, erosion, water management, urbanization, reclamation, agriculture, governance, pollution, geomorphology, economic development, socio-economic changes, and delta wetlands; relative sea level change; sediment trapping; sand mining; salinity intrusion; coastal restoration; estuarine engineering; shoreline evolution; estuarine processes; and the names of specific river basin deltas. Review Results/Synthesis and Discussion . Deltas provide humans important resources and ecosystem services leading to their intensive development. The impacts of this development, together with sea-level rise, threatens the sustainability of many river deltas. Various management and governance measures are available to help sustain deltas. Controls on land use, improved farming and transport technology, wetland habitat protection, and d improved governance are some that might help sustain the economic and ecological services provided by deltas. However, increased population growth and the impacts of climate change will put increased pressure on deltas and the benefits derived from them.

Keywords

• river deltas
• delta sustainability
• delta vulnerability
• delta resilience
• delta ecology
• delta urbanization