System functioning as a basis for sustainable management of deltaic ecosystems

Deltas are very important ecologically and economically, and much of the world's coastal wetlands are located in deltas. These areas are in crisis because various human impacts have led to deterioration of deltas. In this article, we address the functioning of deltas, human impacts in deltas, and the concept of sustainable management of deltas. It is implicit in this discussion that only management that is based on the functioning of deltas is sustainable. In spite of sea‐level rise and subsidence, deltas have greatly increased in area because of riverine sediment delivery over the past several thousand years. Recently, human impacts have altered natural pulsing energies and sediment distribution. It is clear that deltas are not being managed in a sustainable manner and there is a need to move toward more sustainable management. Such management must be based on a carefully controlled return to the natural functioning of deltas by utilizing, rather than diminishing, beneficial natural pulsing energies. We propose ways to determine if deltas are geomorphically, ecologically, and economically sustainable. The article is concluded with an EMergy analysis to holistically test for deltaic sustainability.