"Bacterial Biogeochemistry, Third Edition" focuses on bacterial metabolism and its relevance to the environment, including the decomposition of soil, food chains, nitrogen fixation, assimilation and reduction of carbon nitrogen and sulfur, and microbial symbiosis. The scope of the new edition has broadened to provide a historical perspective, and covers in greater depth topics such as bioenergetic processes, characteristics of microbial communities, spatial heterogeneity, transport mechanisms, microbial biofilms, extreme environments and evolution of biogeochemical cycles.
Provides up-to-date coverage with an enlarged scope, a new historical perspective, and coverage in greater depth of topics of special interestCovers interactions between microbial processes, atmospheric composition and the earth's greenhouse propertiesCompletely rewritten to incorporate all the advances and discoveries of the last 20 years such as applications in the exploration for ore deposits and oil and in remediation of environmental pollution

Origin and Early Evolution of Life draws on evidence from molecular genetics, the structure and function of extant organisms, and geology. It covers the period from about 4 billion years ago, when life is thought to have originated, to about 600 million years ago when multicellular organisms first arose. There are significant gaps in our understanding of the earliest evolution of life forms, but an insight into the topic leads to a more profound understanding of life itself. Particular emphasis is placed on the fact that although life arose very soon after the origin of the Earth, it was represented only by simple microbial life forms for approximately 85% of this time. Increase in complexity beyond the microbial level took place only very late in the history of life.

This book is written for ecologists and protozoologists. Ecologists who study environments and biotic communities in which protozoa are im- ponant should find this book especially useful. During the last decade it has become clear that protozoa play important roles in natural eco- systems, but few ecologists have a feeling for the functional properties and the diversity of these organisms. Protozoa pose or exemplify many general problems of population and community ecology, and of evo- lutionary biology. In most respects the general ecological propenies of protozoa are not fundamentally different from those of larger organisms; yet, due to their small size, short generation times, and ubiquitous oc- currence they often present ecological phenomena in a new and dif- ferent light. To this should be added that protozoa are well-suited for experimental work. Despite these advantages, the study of protozoa has played a relatively modest role in the development of ecology and ev- olutionary biology, primarily, I believe, because most ecologists are unfamiliar with these organisms. I hope this book will attract more attention to these favorable characteristics of protozoa. I also hope that this book may make protozoologists aware of new aspects of their pet organisms. For a long time (that is, until the fun- damental distinction between prokaryotic and eukaryotic cells was rec- ognized) protozoa were believed to represent the simplest form of life. They were therefore extensively used for the experimental study of basic questions of cell biology.