Deltas around the world occupy approximately 1% of the Earth’s land area but are home to more than 500 million people living within 5 meters of present day sea level. They are environmental and economic hot spots with high productivity and rich biodiversity (e.g. Hoanh et al., 2010). Yet deltaic systems are one of the world’s most vulnerable natural systems, residing at the boundary of land and ocean, and subject to upstream human control that depletes them of water and sediment, local resource exploration that contributes to subsidence, and climatic impacts such as sea level rise that contribute to loss of land, saltwater intrusion, and ecosystem degradation. Deltas are vulnerable to hurricanes and tropical storms as hurricane Katrina in August 2005 amply demonstrated in the Mississippi River delta and cyclone Nagris in April 2008 in the coast of Myanmar (UNEP, 2009). Deltas are both resilient – naturally able to build themselves up in response to sea-level rise – and vulnerable in that small changes in topography, sediment or nutrient supply, and/or salinity can provoke dramatic physical and biological changes, as evidenced for example by loss of protective coastal mangrove forests worldwide. There is perhaps no surface environment where there is such a well-balanced interplay of physical processes of sedimentation and erosion that shape the delta and its network of channels and islands; biotic processes by which plants colonize areas based on elevation, salinity, and inundation; and microbial communities interact with fresh and salt-water domains to mediate pore water geochemistry and peat oxidation. The vulnerability of deltas around the world has been articulated in many recent high level publications including the IPCC Fourth Assessment report.
Complementary research programs on Deltas
The DELTAS project, funded by the Belmont Forum, an international collaboration of scientific research funding agencies, aims to develop a science-based integrative modeling framework that can be used to assess delta vulnerability and guide sustainable management and policy decisions at the regional and local scales. The main premise of the project is that although each delta is unique, integrative frameworks that capture the socio-ecological workings of these systems can be developed and encapsulated in decision support tools that can be adopted locally in collaboration with regional experts and stakeholders, for sustainable delta management.
Research Framework and Objectives
The project's research framework comprises five different components, referred to as “Work Packages”:
- Delta-SRES: Develop a theoretical framework for assessing delta vulnerability and the possibility for transitions to undesired biophysical or socio-economic states under various scenarios of change.
- Delta-RADS: Develop an open-access, science-based, integrative modeling framework called the Delta Risk Assessment and Decision Support (RADS) Tool. This tool will be a GIS modeling system that will support quantitative mapping and definition of functional relationships of the bio-physical environment of deltas as well as their social and economic dynamics.
- Delta-DAT: Consolidate data on bio-physical, social, and economic parameters into an international repository of integrated data sets and make these readily available to the community.
- Delta-GDVI: Develop Global Delta Vulnerability Indices that capture the current and projected physical-social-economic status of deltas around the world (“delta vulnerability profiles”). The GDVI is envisioned to be useful in identifying and supporting critical needs and priorities for research, funding, and action.
- Delta-ACT: Work with regional teams and stakeholders to demonstrating the implementation of the developed framework to three major deltas: Ganges-Brahmaputra-Meghna (GBM), Mekong, and Amazon, leveraging numerous ongoing research projects and regional contacts of the DELTAS partners.
Key components of the DELTAS project, whereby deltas are treated as fully coupled socio-ecological systems and scientist-stakeholder feedback is emphasized at all levels.
The fundamental science questions driving the DELTAS project include: (1) How do climate change, pressure on resources, and engineering/ infrastructure development make delta people, biodiversity, and ecosystems vulnerable? (2) How is this vulnerability to be measured? (3) How do delta areas absorb extreme events? What are the hydrological and ecological thresholds underlying the integrity of a delta region? (4) What are the relevant local and regional biophysical and social stressors for a particular delta system, how do these interact, and how do they vary spatially and over time? (5) How can regional delta sustainability be balanced with economic growth? and (6) How can one reduce future risk while attaining sustainable development?
Partner Institutions: University of Minnesota (lead institution, USA), University of Dhaka (Bangladesh), Aix-Marseille Univ. (France), Indiana University (USA), Deltares (Netherlands), German Aerospace Center (Germany), World Wide Fund for Nature – Greater Mekong Program (Vietnam), Vanderbilt University (USA), International Union for the Conservation of Nature (USA), United Nations Environment Programme (France), Univ. of Southampton (UK), Vietnam Academy of Science and Technology (Vietnam), University of Colorado, Boulder (USA), Anna University (India), United Nations University (France), Geological Survey of Japan (Japan), Bangladesh Univ. of Engineering and Technology (Bangladesh), Norwegian Institute for Air Research (Norway), Natural Resources Canada (Canada), University of Waterloo (Canada), and Nanjing University (China).
Belmont Forum and G8 Research Councils Initiative on Multilateral Research Funding – International Opportunities Fund G8MUREFU3-2201-037.