The world population in 1930 was 2 billion. It reached 3 billion in 1960, stands at 4. 6 billion today, and is expected to reach 6 billion by the end of the century. The food and fiber needs of such a rapidly increasing population are enormous. One of the most basic resources, perhaps the most basic of all, for meeting these needs is the soil. There is an urgent need to improve and protect this resource on which the future of mankind directly depends. We must not only learn how to use the soil to furnish our immediate needs, but also ensure that the ability of the soil to sustain food production in the future is unimpaired. This is indeed a mammoth task; a 1977 United Nations survey reported that almost one-fifth of the world's cropland is now being steadily degraded. This volume is the first of a new series entitled Advances in Soil Science. The diversity of soil makes it necessary for research to be conducted in many locations. There are basic principles, however, that are universal. This new series will present clear and concise reviews in all areas of soil science for everyone interested in this basic resource and man's influence on it. The purpose of the series is to provide a forum for leading scientists to analyze and summarize the available scientific information on a subject, assessing its importance and identifYing additional research needs.

The steadily increasing cost of nitrogen fertilizer has resulted in more emphasis on basic and applied studies to improve nitrogen use efficiency in lowland rice. The efficiency of fertilizer nitrogen in farmers' fields is shockingly low ~ a luxury resource-scarce farmers in tropical Asia can ill afford. We believe it is critical to quantify the basic transformation processes and develop management practices for higher N use efficiency for two reasons. They are: 1. Nitrogen fertilizer together with water management is a key factor for achieving the yield potentials of modern rices. 2. Fertilizer nitrogen prices are high and most Asian rice farmers are poor. The International Rice Research Institute (IRRI), Philippines; Internation al Fertilizer Development Center (IFDC), USA; Commonwealth Scientific and Industrial Research Organization (CSIRO), Australia; U.S. Universities (Louisiana, Cornell, California, Arkansas and others); and Dr Justus Leibig University in West Germany are actively engaged in individual or collaborative research that addresses basic transformation processes on N gains and losses and management practices to maximize N use efficiency in rice. It is appropriate to update and summarize, in a double issue of Fertilizer Research, the 10 papers presented at the special symposium organized by the American Society of Agronomy (ASA) at the 75th Annual Meeting in Washington, D.C. in 1983. S.K. De Datta, Head of Agronomy Department, IRRI, was chairman of the International Agronomy Division of ASA (A-6) in 1982 and 1983.

Although this book is about a specific area of the world (i.e., Gotland, Sweden), the interdisciplinary nature of the study, with regard to resources, environment, and society, makes it of interest to a number of fields. We have tried to make this book readable for a wide variety of interested parties including systems ecologists, environmental scientists, resource economists, geographers, regional planners, and regional scientists, as well as those interested in Nordic conditions. Since this project was part of UNESCO's Man and the Biosphere (MAB) pro gram, this book should be of general interest to the international community. This book is certainly not a textbook, but we see it as being useful for courses in regional analysis with plenty of examples for illustrating analysis and models related to energy, environment, and economics, or to the general field of systems ecology. An instructor could, of course, supplement the material on systems and models with other sources. We hope this small book will serve as a helpful example of the analysis of the complex interdisciplinary problems associated with resources and society. In Chapter 1, we present a brief introduction to the Gotland study as well as to some of the concepts and theories that have guided our investigations."

Forty years ago, when PLANT AND SOIL first appeared, Europe was still recovering from the devastating effects of World War II. During the war years, work in many centres of agricultural research had come to a virtual standstill. Buildings and equipment were destroyed, scientists were often forced to terminate their research and teaching activities and funds allocated to such work were diverted to other, at that time, more pressing needs. During the first post-war years reconstruction was undertaken with great zeal and in that light the founding of the new journal PLANT AND SOIL must be viewed. In the pre-war period most agricultural science journals were still primarily national ones and consequently many articles were published in languages mastered by only a limited number of potential readers. In small countries whose languages are not widely understood, the desire arose to publish research findings in one of the major languages. It is therefore understandable that in the early years of the journal's existence, large portions of PLANT AND SOIL were filled with articles from the Scandinavian countries and The Nether lands. Originally, rather frequent use was made of the opportunity to publish also in German and French, but with the advance of English as a major language of communication, a decline was noticeable in the number of German and French manuscripts submitted. As a consequence the Edi torial Board has recently decided to terminate the publishing of articles in these languages."

This book contains the proceedings of the first workshop held at Monte Verita near Ascona, Switzerland on September 24-29, 1989. The workshop was designed to survey the current understanding of water and solute transport through unsaturated soils under field conditions, and to foster research by discussing some unresolved key issues relative to transport modeling and experimentation in four "Think Tank" groups. The first part of this book consists of the reports prepared by the Think Tank groups, who discussed the following topics: modeling approaches, effective large scale properties, evaluation of filed properties, and the role preferential flow. The second part contains a selection of reviewed original contributions presented at the workshop, with topics ranging from the presentation of results from large scale experiments, to improved or new modeling approaches, and to legal or policy aspects. This book is intended for researchers in soil science, hydrology, and environmental engineering who have an interest in transport and reaction processes in the unsaturated zone. It will provide them with a representative sample of current research activities, and with a group discussion of future research directions in four important areas of water and solute transport.

Pesticides in ground, surface and drinking water are a hot topic under continuing discussion. This complete and authoritative volume draws together information on all key issues on the fate and behaviour of pesticides in water systems. The scope of the practice-oriented contributions and the eminence of contributing authors make it an important source for researchers and practitioners in the plant protection and crop science field.

Coated grains have always attracted attention, at first of naturalists, and later of geologists, and the interest in these peculiar bodies was re lated both to their intriguing form and their significance in facies inter pretation and sedimentology and to their relevance to accumulations of hydrocarbons and other mineral deposits. This resulted in numerous publications on this subject, and the intention of this volume is to sum marize the present state of knowledge on coated grains. The idea of the book was to unite some general papers with papers reporting case studies of both recent and ancient coated grains. The organization of the book follows this intention. The papers presented in this volume have been invited by the editor; the theme of the book merits a few words of personal history. The development of studies of coated grains during the last two decades has not only resulted in a great increase in knowledge of recent and ancient environments of coated grain formation, but also numerous important and controversial questions of classification, environmental significance, mineralogical composition etc. of ancient coated grains have arisen. To answer these questions, in 1978 I started the study of many ancient and recent occurrences of coated grains at the Institut fUr Geologie, Ruhr-UniversiUH Bochum, following the invitation of Hans Fiichtbauer and sponsored by the Alexander von Humboldt-Stiftung."

Integration of ichnological information into sedimentological models, and vice versa, is one of the main means by which we can improve our understanding of ancient depositional environments. Mainly intended for sedimentologists, this book aims to make ichnological methods as part of facies interpretation more popular, providing an analytical review of the ichnology of all major depositional environments and the use of ichnology in biostratigraphic and sequence stratigraphic analysis.

It starts with an introduction to the historical aspect of ichnology, introducing common concepts and methods, and then continues with parts treating the main depositional systems from continental, shallow-marine and deep-marine siliciclastics, and marine carbonates. The last part is dedicated to the ichnology in hydrocarbon reservoir and aquifer characterization.
First overview in 25 years of the status of ichnological studies in facies reconstructions of all major depositional environmentsWritten by a selected, well-experienced and specialized international authorshipProvides easy access to the comprehensive and widespread literature

Knowledge in the field of acidic deposition is expanding rapidly, and both ex perts and non-experts are challenged to keep up with the latest information. We designed our assessment to include both the basic foundation needed by non experts and the detailed information needed by experts. Our assessment in cludes background information on acidic deposition (Chapter 1), an in-depth discussion of the nature of soil acidity and ecosystem H+ budgets (Chapter 2), and a summary of rates of deposition in the Southeastern U.S. (Chapter 3). A discussion of the nature of forest soils in the region (Chapter 4) is followed by an overview of previous assessments of soil sensitivity to acidification (Chapter 5). The potential impacts of acidic deposition on forest nutrition are described in the context of the degree of current nutrient limitation on forest productivity (Chap ter 6). The results of simulations with the MAGIC model provided evaluations of the likely sensitivity of a variety of soils representative of forest soils in the South (Chapter 7), as well as a test of soil sensitivity criteria. Our synthesis and recommendations for research (Chapter 8) also serve as an executive summary. A complementary volume in the Springer-Verlag Ecological Studies series should be consulted for information on European forests. This volume, Acidic Deposition and Forest Decline in the Fictelgebirge, edited by E.-D. Schultze and O.L. Lange, also provides greater detail on the physiologic responses of trees than we present in our regional assessment."

The purpose of Advances in Soil Science is to provide a forum for leading scientists to analyze and summarize the available scientific information on a subject, assessing its importance and identifying additional research needs. A wide array of subjects has been addressed by authors from many countries in the initial ten volumes of the series. The quick acceptance of the series by both authors and readers has been very gratifying and confirms our perception that a need did exist for a medium to fill the gap between the scientific journals and the comprehensive reference books. This volume is the first of the series devoted entirely to a single topic soil degradation. Future volumes will include both single-topic volumes as well as volumes containing reviews of different topics of soil science, as in the case of the first ten volumes. There are increasing concern and attention about managing natural re sources, particularly soil and water. Soil degradation is clearly one of the most pressing problems facing mankind. Although the spotlight regarding soil degradation in recent years has focused on Africa, concern about the degradation of soil and water resources is worldwide. The widespread con cern about global environmental change is also being linked to severe problems of soil degradation. Therefore, we are indeed pleased that the first volume of the series devoted to a single topic addresses such an impor tant issue. The current volume is also the first of the series involving a guest editor."

In the early 1980s there were several published reports of recent, unexplained increases in mortality of red spruce in the Adirondack Mountains and the northern Appalachian Mountains of the eastern United States. These reports coincided with documentation of reductions in radial growth of several species of pine in the southeastern United States, and with the severe, rapid, and widespread decline of Norway spruce, silver fir, and some hardwoods in central Europe. In all of these instances, atmospheric deposition was hypothesized as the cause of the decline. (Throughout this volume, we use the term "decline" to refer to a loosely synchronized regional-scale deterioration of tree health which is brought about by a combination of stress factors. These may be biotic or abiotic in nature, and the combinations may differ from site to site. ) Heated public debate about the causes and possible cures for these forest declines ensued. Through the course of this debate, it became clear that information about forest health and air pollution effects on forests was inadequate to meet policymakers' needs. Ecology and Decline of Red Spruce in the Eastern United States addresses that gap for eastern spruce fir forests and represents the culmination of a great deal of research conducted in recent years. The focus is on red spruce because the decline of red spruce was both dramatic and inexplicable and because of the great amount of information gathered on red spruce.

"Dredged Material and Mine Tailings" are two of the same thing once they are deposited on land: they must be safe-guarded, wash-out must be prevented, and they must be protected by a plantcover. This comprehensive two-volume treatise covers both important aspects of their management: "Environmental " "Management of Solid Waste" turns to the practical applications, such as prediction, restoration and management, while in "Chemistry and Biology of Solid Waste" the principles and assessment are scientifically studied and discussed. Previously, dredged material was a commodity, it could be sold as soil, e. g. to gardeners. In the meantime, dredged material from the North Sea (e.g. the Rotterdam or Amsterdam harbor) must be treated as hazardous waste. Many environmentalists, managers and companies do not know how to solve the inherent problems. This new work deals with the chemical, physical and biological principles; the biological and geochemical assessment; the prediction of effects and treatment; and finally, with restoration and revegetation. It is written by many leading scientists in the various fields, and will prove invaluable for managers and politicians who are concerned with the present environmental situation.

The Australasia-Pacific Region supports approximately 50% of the world's population. The last half-century has witnessed a rapid increase in the regional population, agricultural productivity, industrial activities and trade within the region. Both the demand for increased food production and the desire to improve the economic conditions have affected regional environmental quality. This volume presents an overview of the fate of contaminants in the soil environment; current soil management factors used to control contaminant impacts, issues related to sludge and effluent disposals in the soil environment; legal, health and social impacts of contaminated land, remediation approaches and strategies to manage contaminated land, some of the problems associated with environmental degradation in the Australasia-Pacific Region and steps that we need to take to safeguard our environment.

The soil is the medium through which pollutants originating from human activities, both in agriculture and industry, move from the land surfaces to groundwater. Polluting substances are subject to complex physical, chemical and biological transformations during their movement through the soil. Their displacement depends on the transport properties of the water-air-soil system and on the molecular properties of the pollutants. Prediction of soil pollution and restoration of polluted soils requires an under standing of the processes controlling the fate of pollutants in the soil medium and of the dynamics of the contaminants in the un saturated zone. Our book was conceived. as a basic overview of the processes governing the behavior of pollutants as affected by soil constituents and environmental factors. It was written for the use of specialists working on soil and unsaturated zone pollution and restoration, as well as for graduate students starting research in this field. Since many specialists working on soil restoration lack a back ground in soil science or a knowledge of the properties of soil pollutants, we have included this information which forms the first part of the book. In the second part, we discuss the partitioning of pollutants between the aqueous, solid and gaseous phase of the soil medium. The retention, transformation and transport of pollutants in the soils form the third section."

Tarquin Teale, a sedimentology/stratigraphy postgraduate student at the Royal School of Mines, was killed in a road accident south of Rome on 17 October 1985. Premature death is a form of tragedy which can make havoc of the ordered progress which we try to impose on our lives. As parents, relatives and friends, we all know this, and yet somehow when it touches our own world there is no consolation to be found anywhere. In Tarquin's case the enormity of the loss felt by those of us who knew him can barely be expressed in words. Tarquin had everything which we aspire to. His fellow graduate students envied his dramatic progress in research. We his advisors, in appreciating this progress, marvelled at how refreshingly rare it was to see such precocious talent combined with such a caring, modest and well-balanced personality. He was des tined for the highest honours in geoscience and there is no doubt that he would have lived a life, had he been granted the chance, which would have spread colour, intellectual insight and goodness."

This series is dedicated to serving the growing community of scholars and practitioners concerned with the principles and applications of environmental management. Each volume is a thorough treatment of a specific topic of importance for proper management practices. A fundamental objective of these books is to help the reader discern and implement man's stewardship of our environment and the world's renewable resources. For we must strive to understand the relationship between man and nature, act to bring harmony to it, and nurture an environment that is both stable and productive. These objectives have often eluded us because the pursuit of other individual and societal goals has diverted us from a course of living in balance with the environment. At times, therefore, the environmental manager may have to exert restrictive control, which is usually best applied to man, not nature. Attempts to alter or harness nature have often failed or backfired, as exemplified by the results of imprudent use of herbicides, fertilizers, water, and other agents. Each book in this series will shed light on the fundamental and applied aspects of environmental management. It is hoped that each will help solve a practical and serious environmental problem.

In March, 1983 a workshop on Pollutants in Porous Media was hosted by the Institute of Soils and Water of the Agricultural Research Organi zation in Bet Dagan, Israel. At this workshop, the unsaturated zone be tween the soil surface and groundwater was the focal point of discus sions for scientists from various disciplines such as soil chemists, physicists, biologists and environmental engineers. Since then, the prob lem of soil and water pollution has only worsened as more and more cases of pollution caused by human activities including agriculture and industry have been revealed. A great deal of work has been carried out by environmental scientists since 1983 in elucidating the behavior of the many classes of pollutants and the complex physical, chemical, and bio logical transformations which they undergo as they move through the soil to the vadose zone and, in many cases, the groundwater. In light of this, it was felt that another meeting of specialists from the many disciplines which deal with this subject was necessary and so a Second International Workshop on the Behavior of Pollutants in Porous Media, sponsored by IUPAC (the International Union of Pure and Applied Chemistry) and IAHS (the International Association of Hydrological Sciences), was organized and held in the Institute of Soils and Water of the Agricultural Research Organization in Bet Dagan, Israel during 1987. June, The present volume is a selection of the talks presented at this second workshop and deals only with toxic organic chemicals in porous media."

This series is dedicated to serving the growing community of scholars and practitioners concerned with the principles and applications of environ mental management. Each volume is a thorough treatment of a specific topic of importance for proper management practices. A fundamental ob jective of these books is to help the reader discern and implement man's stewardship of our environment and the world's renewable resources. For we must strive to understand the relationship between man and nature, act to bring harmony to it, and nurture an environment that is both stable and productive. These objectives have often eluded us because the pursuit of other in dividual and societal goals has diverted us from a course of living in balance with the environment. At times, therefore, the environmental manager may have to exert restrictive control, which is usually best applied to man, not nature. Attempts to alter or harness nature have often failed or backfired, as exemplified by the results of imprudent use of herbicides, fertilizers, water, and other agents. Each book in this series will shed light on the fundamental and applied aspects of environmental management. It is hoped that each will help solve a practical and serious environmental problem."

The importance of mycorrhiza for the improvement of plant growth is increasingly being realised in Agriculture and Forestry and several mycorrhizal fungi have been commercially recognised for the purpose. The aim of this book is to describe the various techniques used to study the mycorrhizal biology. Problems with preparing such a book are many. Mainly mailing of manuscripts to and from authors resulted in irregular and final editing. Every effort was made not to change the peer review original manuscript to ensure accuracy. Our sole aims is to communicate to the greatest extent possible a current world need in mycorrhizal research. Plant productivity is regulated by microbial associations established in the plant root systems. The interactions of microorganisms and plant roots are especially important in providing nutritional requirements of the plant and the associated microorganisms. Plant growth and development are controlled largely by the soil environment in the root region -rhizosphere. This is a very complex environment in which the effects of the plant on soil microorganisms and the effects of microorganisms on the plant are interacting, interdependent and highly complex. Plant root exudates and breakdown products feed the microbes and the microbe in tum often benefit the plant. Mycorrhizal fungi are important tools for increasing growth, development and yield of economically important plants, they play important role of biofertilizer which can help establish plants in nutrient deficient soils, particularly phosphorus deficient soils, arid, semi-arid and waste lands.

Sequence stratigraphy has advanced considerably since the early applications of the concepts on seismic data. It attempts to discern the migration of facies re sulting from changes in a combination of factors such as, sea level, tectonics, climate and sediment flux, and integrates it with a meaningful chronostratigraphy. The stratigraphic record is envisioned as a framework of repetitive packages of genetically-related strata, formed in response to the shifting base level, in which the locus of deposition of various sediment types may be anticipated. This attribute is rapidly promoting sequence stratigraphy as an indispensable tool for prediction of facies in exploration and production geology. In hydrocarbon exploration the application of sequence stratigraphy has ranged from anticipating reservoir- and source-rock distribution to predicting carbonate diagenesis, porosity and permeability. The capability to anticipate vertical and lateral distribution of facies and reservoir sands in the basinal, shoreface, incised valley-fill and regressive settings alone has been a great asset for exploration. In frontier areas, where data are often limited to seismic lines, sequence-stratigraphic methodology has helped determine the timing and of types of unconformities and anticipate transgressive- and regressive-prone intervals. In production it is aiding in field development by providing improved source and seal predictions for secondary oil recovery. A recognition of stratigraphic causes of poor recovery through improved understanding of internal stratal architecture can lead to new well recompletions and enhanced exploitation in existing fields. The sequence-stratigraphic discipline is in a state of rapid expansion."

Three symposia on environmental geochemistry in tropical countries, held in Niter6i, Brazil (1993), in Cartagena, Colombia (1996) and in Nova Friburgo, Brazil (1999), made it very clear that tropical geochemistry is of world standard and fast increasing in multi disciplinarily and impact on important geochemical paradigms. It has additionally strong links with the economy of tropical countries, such as mining and industrialisa tion and is in full development for treating environmental problems caused by human activities of urban or industrial origin. We must compliment Prof. Jorge Abriio and his colleagues in Brazil and Dr. Gloria Prieto and her colleagues in Colombia for these ini tiatives. The participation of respectively 180 and 150 scientists, coming from 15 different countries for the first and second symposia, has shown that a large interest exists for tropical environmental geochemistry. It also demonstrates the necessity to understand tropical environmental problems. The organisation of a large international symposium is not possible without the assistance of state and federal authorities, for which those of Brazil and Colombia have to be complimented. The 3rd Symposium on Environmental Geochemistry in Tropical Countries was the last of the series and was attended by 22 countries and 170 participants and treated a number of related environmental and economic problems."

Landscapes of the past have always held an inherent fascination for ge ologists because, like terrestrial sediments, they formed in our environment, not offshore on the sea floor and not deep in the subsurface. So, a walk across an ancient karst surface is truly a step back in time on a surface formed open to the air, long before humans populated the globe. Ancient karst, with its associated subterranean features, is also of great scientific interest because it not only records past exposure of parts of the earth's crust, but preserves information about ancient climate and the movement of waters in paleoaquifers. Because some paleokarst terranes are locally hosts for hydrocarbons and base metals in amounts large enough to be economic, buried and exhumed paleokarst is also of inordinate practical importance. This volume had its origins in a symposium entitled "Paleokarst Systems and Unconformities-Characteristics and Significance," which was orga nized and convened by us at the 1985 midyear meeting of the Society of Economic Paleontologists and Mineralogists on the campus of the Colorado School of Mines in Golden, Colorado. The symposium had its roots in our studies over the last decade, both separately and jointly, of a number of major and minor unconformities and of the diverse, and often spectacular paleokarst features associated with these unconformities."

The NATO Advanced Research Workshop from which this book derives was conceived during Biotec-88, the Second Spanish Conference on Biotechnology, held at Barcelona in June 1988. The President of the Conference, Dr. Ricardo Guerrero, had arranged sessions on bacterial polymers which included lectures by five invited participants who, together with Dr. Guerrero, became the Organizing Committee for a projected meeting that would focus attention upon the increasing international importance of novel biodegradable polymers. The proposal found favour with the NATO Science Committee and, with Dr. R. Clinton Fuller and Dr. Robert W. Lenz as the co-Directors, Dr. Edwin A. Dawes as the Proceedings Editor, and Dr. Hans G. Schlegel, Dr. Alexander J.B. Zehnder and Dr. Ricardo Guerrero as members of the Organizing Committee, the meeting quickly took shape. To Dr. Guerrero we owe the happy choice of Sitges for the venue, a pleasant coastal resort 36 kilometres from Barcelona, which proved ideal. The sessions were held at the Palau de Maricel in appropriately impressive surroundings, and invaluable local support was provided by Mr. Jordi Mas-Castella and by Ms. Merce Piqueras. Much of the preparatory work fell upon the broad shoulders of Mr. Edward Knee, whose efforts are deeply appreciated. The Organizing Committee hopes that this Workshop will prove to be the first of a series which will aim to keep abreast of a rapidly expanding and exciting area of research that is highly relevant to environmental and industrial interests.

Probably more than any other element, iron markedly influences the chemical and physical properties of soils and sediments in the earth. Considering its transition metal status, with potential variation in electronic configuration, ionic radius, and magnetic moment, combined with its abundance and relatively large mass, little wonder that one sees its unique influence on every hand. Pre sentations at the NATO Advanced Study Institute (NATO AS ) on Iron in Soils and Clay Minerals reviewed and discussed the occurrence, behavior, and properties of Fe-bearing minerals found in soils and in the clay mineral groups kaolinite, smectite, and mica. Also discussed at the NATO AS were the basic chemical properties of Fe, methods for separating and identifying Fe in minerals, and the role of Fe minerals in weathering and other soil-forming processes. The present publication is the reviewed and edited proceedings of that Advanced Study Institute. The sequence of chapters follows the general pattern beginning with introductory chapters which overview the general occurrence of Fe in the earth and its chemistry, both generally and in mineral environments, followed by identification and characterization methods for Fe and Fe phases in minerals. The properties and behavior of Fe oxides, Fe-bearing clay minerals, and other Fe minerals in soils are then described, and the text ends with a summary of the role of Fe in soil-forming processes. A Table of Contents and subject index are provided to assist the reader in finding specific topics within the text."

The Gulf of Mexico Basin is one of the most prolific hydrocarbon-producing basins in the world, with an estimated endowment of 200 billion barrels of oil equivalent. This book provides a comprehensive overview of the basin, spanning the US, Mexico and Cuba. Topics covered include conventional and unconventional reservoirs, source rocks and associated tectonics, basin evolution from the Mesozoic to Cenozoic Era, and different regions of the basin from mature onshore fields to deep-water subsalt plays. Cores, well logs and seismic lines are all discussed providing local, regional and basin-scale insights. The scientific implications of seminal events in the basin's history are also covered, including sedimentary effects of the Chicxulub Impact. Containing over 200 color illustrations and 50 stratigraphic cross-sections and paleogeographic maps, this is an invaluable resource for petroleum industry professionals, as well as graduate students and researchers interested in basin analysis, sedimentology, stratigraphy, tectonics and petroleum geology.