Sedimentary Crisis at the Global Scale 2: Deltas, A Major Environmental Crisis [Hardcover]

The great deltas of the globe have been threatened for several decades but their decline now appears to be inevitable; they are receding and losing the fertility that supports their tens of millions of inhabitants. Our deltas are victims of the dramatic deterioration in the volume of continental sediment brought by rivers to the oceans.

By nature, deltas are fragile eco- and geological organisms. For centuries, they have been subject to human actions in the Mediterranean and European world, and today a deep crisis is affecting the great tropical deltas. A chapter is also devoted to concerns facing the Mississippi, an aging delta of the new world.

Sedimentary Crisis at the Global Scale 2 discusses possible strategies to protect the deltas of the world  or at least adapt them and their dependencies to the changes they face. Several models are possible, including comprehensive protection (such as in the Netherlands) and cautious and respectful opening to the forces of the oceans in an environment-first perspective.

Introduction ix

Chapter 1 Deltas: Young, Fragile and Threatened Environments 1

1.1 Long-term construction of deltas: general mechanisms 2

1.1.1 Processes and basic forms 2

1.1.2 Dynamics of construction and redistribution in progress 2

1.1.3 Young and unstable areas 5

1.2 Some of the Earths last great natural deltas: two deltas in the Arctic 8

1.2.1 The Lena Delta 8

1.2.2 The Mackenzie Delta 9

1.3 The Earths deltas: what is their current situation in the face of terrestrial and marine constraints? 11

1.3.1 The rise in sea levels 11

1.3.2 Sedimentary exhaustion of continents 13

1.3.3 Extraction of resources and accelerated subsidence of dell³c