Scientists who have had the opportunity of being associated with Professor Egon T. Degens, to whom this Festschrift is devoted, have been influenced by his ideas on subjects as varied as: extraterrestrial organic matter, origin of life, evolution of organisms, isotope biogeochemistry down to more imminent ones such as the carbon cycle and its implications on climate. This variety is also reflected in the papers in the present volume contributed by colleagues who have known Egon or have worked with him. Egon Theodor Degens was born on April 16, 1928 at Inden, Germany and had his education in Bonn and Wiirzburg. After a stint at the Pennsylvania State University he returned to Wiirzburg to help set up one of the first organic geochemistry laboratories in the world. This laboratory was the breeding ground for some of the eminent organic geochemists at work today. Later, he joined the California Institute of Technology and began his work on stable carbon isotopes, and later on biogeochemical compounds in natural waters. From California he moved on to the east coast, which led to yet another productive phase at the Woods Hole Oceanographic Institution. He was instrumental in the pioneering work carried out by the Woods Hole scientists in the Black Sea which is the largest anoxic basin in the world, and in the Red Sea where the first hydrothermal ore deposits on the seafloor were discovered.

Scientists who have had the opportunity of being associated with Professor Egon T. Degens, to whom this Festschrift is devoted, have been influenced by his ideas on subjects as varied as: extraterrestrial organic matter, origin of life, evolution of organisms, isotope biogeochemistry down to more imminent ones such as the carbon cycle and its implications on climate. This variety is also reflected in the papers in the present volume contributed by colleagues who have known Egon or have worked with him. Egon Theodor Degens was born on April 16, 1928 at Inden, Germany and had his education in Bonn and Wiirzburg. After a stint at the Pennsylvania State University he returned to Wiirzburg to help set up one of the first organic geochemistry laboratories in the world. This laboratory was the breeding ground for some of the eminent organic geochemists at work today. Later, he joined the California Institute of Technology and began his work on stable carbon isotopes, and later on biogeochemical compounds in natural waters. From California he moved on to the east coast, which led to yet another productive phase at the Woods Hole Oceanographic Institution. He was instrumental in the pioneering work carried out by the Woods Hole scientists in the Black Sea which is the largest anoxic basin in the world, and in the Red Sea where the first hydrothermal ore deposits on the seafloor were discovered.

Modern Biogeochemistry is aimed to generalize modern ideas of biogeochemical developments during the last decades. It is designed to support a general course in biogeochemistry, and as such, is likely to have a broad market among the many universities and colleges that are adding such courses to their curricula. This book aims to supplement the existing textbooks by providing modern understanding of biogeochemistry, from evolutionary biogeochemistry to practical applications of biogeochemical ideas such as human biogeochemistry, biogeochemical standards and biogeochemical technologies. To a certain extent this textbook is a summary of both scientific results of various authors and classes in biogeochemistry, that have been given to students by authors during the last 5 to 10 years at different universities throughout the world such as Cornell, Moscow, Seoul and Bangkok. Biogeochemistry is becoming an increasingly popular subject for graduate and postgraduate education. Courses in ecology, geography, biology, chemistry, environmental science, public health and environmental engineering all tend to have a biogeochemical component in their syllabuses to a greater or lesser extent.

This book is aimed at generalizing the modern ideas of both biogeochemical and environmental risk assessment that have been developed in recent years. Only a few books are available in this interdisciplinary area, since most deal mainly with various technical aspects of ERA description and calculations. This text aims at supplementing the existing books by providing a modern understanding of mechanisms responsible for ecological risks for human beings and ecosystems.

Floodplains are ecosystems which are driven by periodic inundation and oscillation between terrestrial and aquatic phases. An understanding of such pulsing systems is only possible by studying both phases and linking the results into an integrated overview. This book presents the results of a 15-year study of the structure and function of one of the largest tropical floodplains, the Amazon River floodplain. It covers qualitative aspects, e.g., adaptations of aquatic and terrestrial organisms to the flood pulse as well as quantitative aspects, e.g., studies of biomass, primary production, decomposition, and nutrient cycles. The authors interpret their findings and the most important data from other studies under an integrating scientific concept, the Flood Pulse Concept.

Geobiology is an exciting and rapidly developing research discipline that opens new perspectives in understanding Earth as a system. To determine and to exploit its possibilities, this promising scientific field will benefit from a discussion of its definition as a research discipline, its objectives, and its methodological approaches. Such a spirited discussion is the goal of the book "Geobiology: Objectives, Concepts, Perspectives". Geobiology touches various subdisciplines of geology and biology in many ways. The book will serve biogeochemists, paleontologists, biomineralogists, microbiologists and many others as a forum to determine future directions of geobiological research. The book includes a section on the concept of geobiological studies, which combines the parent disciplines biology and geology. Several case studies describe geobiological investigations that serve to understand Earth in the present and past. The case studies give an overview of the general understanding of geobiology and lead the reader towards the current hot topics in this rising scientific discipline.* New definition of the rising scientific discipline "geobiology"* Overview into the broad spectrum of geobiological topics* Insight into hot topics of current geobiological research

This volume contains a selection of papers presented to the Fourth Internation~l Symposium on Environmental Biogeochemistry (ISEB), and a conference on Biogeochemistry in Relation to Mining Industry and Environmental Pollution (Leaching Conference), held in Canberra, Aust ralia on August 26-31 and September 3-4, 1979, respectively. The ISEB were established to provide "a forum for uninhibited exchange of information and ideas among the biological, chemical, atmospheric and geolorical scientists working in the common area of biogeochemistry, encompassing soil and other earth sciences as well as the hydrosphere and atmosphere", By linking the fourth ISEB with the Leachin~ Conference the scope of discussions was extended to encompass the application of biogeochemical processes to the mining industry. This wide-ranging philosophy is reflected in the breadth and diversity of the subjects covered in this book. The published papers are expanded versions of those presented at the meetings. They have all been scrutinized by at least one referee in addition to the editors. About 20% of the contributions to the meetings are not included, either because authors did not wish to publish or because the papers were not accepted by the editors.

A sound understanding of the global carbon cycle requires an appreciation of the various physico-chemical and biological processes that determine the production, distribution, deposition and diagenesis of organic matter in the natural environment. This book is a comprehensive interdisciplinary synthesis of this information, coupled with an organic facies approach based on data from both microscopy and bulk organic geochemistry.

This book offers extensive coverage of the most important aspects of UVR effects on all aquatic (not just freshwater and marine) ecosystems, encompassing UV physics, chemistry, biology and ecology. Comprehensive and up-to-date, UV Effects in Aquatic Organisms and Ecosystems aims to bridge the gap between environmental studies of UVR effects and the broader, traditional fields of ecology, oceanography and limnology. Adopting a synthetic approach, the different sections cover: the physical factors controlling UVR intensity in the atmosphere; the penetration and distribution of solar radiation in natural waters; the main photochemical process affecting natural and anthropogenic substances; and direct and indirect effects on organisms (from viruses, bacteria and algae to invertebrate and vertebrate consumers). Researchers and professionals in environmental chemistry, photochemistry, photobiology and cell and molecular biology will value this book, as will those looking at ozone depletion and global change.

This handbook summarizes the main advances in our understanding of marine minerals and concentrates on the deposits of proven economic potential. In cases where our knowledge may be too limited to allow defining of their economic potential, those minerals are covered regionally or by deposit type. Handbook of Marine Mineral Deposits is divided into three sections; Marine placers, manganese nodules and crusts, and deep-sea hydrothermal mineralization. All of these mineral deposits have great potential importance to economic geologists and marine mines. Edited by an acknowledged expert in the field, this handbook includes work by internationally renowned contributors. The new United Nations Law of the Sea, ratified by over 100 countries within the past two years, provides a framework and guidelines for deep-sea mineral exploration that increases international interest in this book. The Handbook serves as a platform from which to launch the more detailed evaluation studies that will need to take place in the 21st century before recovery can continue or commence. Handbook of Marine Mineral Deposits is useful to mineralogists, economic geologists, marine geologists, marine miners, and conservationists. Features