Coral reefs have shaped the surface of our planet far more than has any other ecosystem. They are dynamic systems, producing limestone at the rate of 400-2,000 tons per hectare per year, and influencing the chemical balance of the world's oceans. Coral reefs have been around since before the prairies or other ecosystems of flowering plants existed, yet they vanish about a million years before other groups of organisms each time there is a global mass extinction. They return after each catastrophe, however, following a long period of absence. Although coral reefs are the most productive communities in the sea, the fisheries of coral reefs are among the most vulnerable to overexploitation. Despite having the power to create the most massive structures in the world made by living creatures (including man), the thin veneer of living tissue of coral reef is particularly sensitive to natural disturbances and effects of human activities. Coral reefs are the first to go during periods of climate change, but they have always come back. This combination of attributes, creative power and fragility, resilience and sensitivity, makes management of coral-reef systems a challenge to science. Over 70% of the coral reefs in the Caribbean and Asian waters have been degraded, and perhaps a third of the 400 species of corals in Japanese waters are in danger of local extinction unless effective coastal management practices are established. This book presents what is known about factors that shift the balance between accretion and erosion, recruitment and mortality, stony corals and filamentous algae, recovery and degradation--the life and death of coral reefs. Insight into the factors controlling thedirection of these processes is essential for appropriate management decisions.

This volume investigates the effects of human activities on coral reefs, which provide important life-supporting systems to surrounding natural and human communities. It examines the self-reinforcing ecological, economic and technological mechanisms that degrade coral reef ecosystems around the world. Topics include reefs and limestones in Earth history; the interactions between corals and their symbiotic algae; diseases of coral reef organisms; the complex triangle between reef fishes, seaweeds and corals; coral disturbance and recovery in a changing world. In addition, the authors take key recent advances in DNA studies into account which provides new insights into the population biology, patterns of species distributions, recent evolution and vulnerabilities to environmental stresses. These DNA analyses also provide new understandings of the limitations of coral responses and scales of management necessary to sustain coral reefs in their present states. Coral reefs have been essential sources of food, income and resources to humans for millennia. This book details the delicate balance that exists within these ecosystems at all scales, from geologic time to cellular interactions and explores how recent global and local changes influence this relationship. It will serve as an indispensable resource for all those interested in learning how human activities have affected this vital ecosystem around the world.

Charles Birkeland Living coral is a thin veneer, measured in millimeters. Yet this thin film of living tissue has shaped the face of the Earth by creating limestone structures sometimes over 1,300 m thick from the surface down to its base on volcanic rock (Enewetak Atoll), or over 2,000 km long (Great Barrier Reef). About half the world's coastlines are in the tropics and about a third of the tropical coastlines are made of coral reef. Archipelagoes of hundreds of atolls such as the Marshalls, the Maldives, the Tuamotus, and most of the Carolines and Kiribati have been fonned by coral. In addition to enlarging high islands (such as the entire northern end of Guam) and extending and protecting coastlines, ancient biogenic reefs have fonned even larger areas on the present continents. Shallow living coral 2 reefs are estimated to presently cover over 600,000 km (Smith, 1978). Coral reefs are dynamic systems, producing limestone at the rate of 400-2,000 tons per hectare per year (Chave et aI. , 1972). The Great Barrier Reef dominates 2 230,000 km and has grown to this size in a geologically brief period of a few million years. Coral reefs influence the chemical balance of the world's oceans. Roughly half the calcium that enters the sea each year around the world, from the north to south poles, is taken up and temporarily bound into coral reefs (Smith, 1978).