Saline land is a resource capable of significant production. Recent advances in research in breeding for salt tolerance in wheat, biotechnology in rice, and selection and rehabilitation of salt-tolerant plants are of economic importance in arid/saline conditions.

This book gives some practical approaches for saline agriculture and afforestation, and describes examples of cultivating salt-tolerant/halophytic plants for commercial interest on salt-affected land or with highly salinized water in Australia, China, Central Asia, Egypt, Pakistan, and Russia. It also explores the possibilities of arid/saline agriculture and afforestation in UAE.

After UNCED (United Conference on Environment and Development, Rio de Janeiro, July 1992), a second edition of Desertification was necessary. About 150 corrections, amendments and additions take scientific progress into account. The author also presents an updated chapter in which the results of UNCED are analyzed.
This book aims at an understanding of what is commonly called "desertification" - a term which is proposed to be replaced by "land degradation." Each level of technology, excessive or insufficient, creates its own mismanagement. This is reflected in an increase in land degradation and eventually a decrease in soil productivity. The benefit to the reader is an awareness of the ecozones and a global overview of the phenomena, mechanisms and existing solutions.

Soil degradation is clearly one of the most pressing problems facing man kind. A continuation of soil degradation will eventually lead to a loss in crop productivity even though fertilizers and other inputs often result in increased yields in the short term. Soil degradation also leads to environ mental pollution. A decrease in soil quality invariably leads to a decrease in water quality, and often in air quality. While there is a clear consensus that soil degradation is a major problem, the literature on this subject leaves numerous baffling questions. If statis tics on land degradation are correct, there is a definite cause for concern, and present a mammoth challenge for agricultural scientists. There are those that say the scientific community has over dramatized this issue, and created a credibility problem. Consequently; Volume 11 of Advances in Soil Science was organized by Dr. Rattan Lal who is recognized as a lead ing authority on the subject. The objective of Volume 11 was to assess the types and processes of soil degradation and establish some of the major cause-effect relationships. Volume II documented the seriousness of soil degradation in many parts of the world. Therefore, it seemed immediately important to devote a volume to the principles and technologies for restor ing degraded soils to a productive status. While the land resources are limited, world population is rapidly increasing, particularly in developing countries. Dr."

There are some good reasons to start a global study of beech forests. One reason may be the importance of beech for man. In many places and in many ages, beech has played an important role in people's lives (Table 1). Already in old ages beech was useful for nuts, fuelwood and bokiz, beechwood tablets carved with runes, from which probably our word 'book' is derived. Beech still plays an important role in people's lives. Another reason for a global study of beech forests is that it lifts us above the detailed but fragmented image of a local study. My study of beech forests started out of love for these often beautiful forests, and, gradually, a small project grew into a world wide study. Table 1. Beech names. Scientific name Name Language Meaning - origin beech English bhagos (Indo-European) Fagus sylvatica do Buche, Rotbuche Gennan beuk do Dutch do bok Swedish do bog Danish do Mtre, fayard French hetre = hester (Gennanic), indicating young beeches do haya Spanish do faig Cathalan do faggio Italian do fagus Latin phagos = glutton (Greek), referring to edible nuts do fagul Romanian do buk Czech F. sylvatica subsp. orientalis kayin Turkish Fagus crenata buna Japanese unknown do sobaguri Japanese noodle chestnut (old), indicating hairy cupule penduncles F agus japonica inubuna Japanese inferior beech Fagus spp."

It is our conviction that professional skill in forestry will develop more readily and more efficiently if forestry students are presented with a clear understanding of the im pact of the physical factors that both enhance and inhibit forestry activities. Part I is analytic, written as a basic text for undergradu ates in courses such as logging, transport, forest engineer ing and even forest management. It deals with the fundamen tals of technology in forestry as determined by the physical environment. The analytic approach serves two purposes, to bring about a clear understanding of the real world of the forest and to develop tools through which efficiency and productivity can be explored, understood and improved. The principal author of this volume was Prof. Ulf sundberg. Part II discusses in some detail a wide variety of practical problems encountered by foresters. It describes harvesting systems and the principles of management and control of forest operations. The influence of the forest on operations is described at length, the terrain, topography, forest soils as well as the engineering characteristics of trees and forest stands. It also considers the impact of oper ations on the forest. The principal author of this volume was Dr. Ross Silversides. Chapters 11, 12 and 13 were written by-Prof. Sundberg."

The quality of human life has been maintained and enhanced for generations by the use of trees and their products. In recent years, ever rising human population growth has put a tremendous pressure on trees and tree products; growing awareness of the potential of previously unexploited tree resources; and environ mental pollution have both accelerated the development of new technologies for tree propagation, breeding and improvement. Biotechnology of trees may be the answer to solve the problems which can not be solved by conventional breeding methods. The combination of biotechnology and conventional methods such as plant propagation and breeding may be a novel approach to improving and multiplying a large number of the trees and woody plants. So far, plant tissue culture technology has largely been exploited by commercial companies in propagation of ornamentals, especially foliage house plants. Gene rally, tissue culture of woody plants has been recalcitrant. However, limited success has been achieved in tissue culture of angiosperm and gymnosperm woody plants. A number of recent reports on somatic embryogenesis in woody plants such as Norway spruce (Picea abies), Loblolly pine (Pinus taedb), Sandalwood (Santalum album), Citrus, mango (Mangifera indica), etc., offer a ray of hope of: a) inexpensive clonal propagation for large-scale production of plants or "emblings" or somatic seedlings; b) protoplast work; c) cryopreservation; d) genetic transformation; and e) synthetic or artificial or manufactured seed production."

In the course of almost 40 years various researchers, at what used to be TNO's Forest Products Research Institute, currently the TNO Centre for Timber Research, conducted studies into the physical properties of wood. The first studies and calculations were carried out by Mr E. Prochaska, after which Mrs G.M.C. Koning-Vrolijk continued the work. Indeed Mrs Koning-Vrolijk wrote the Institute's first publication (1962), an Eng lish version of which was published in 1963 (3) on the occasion of FAO and IUFRO Conferences held in the United States. Thereafter, the Institute's work was carried on by Mr A. Govers, Mr J.F. Rijsdijk and Mr P.B. Laming. Their research resulted in a second publication (Laming 1978) in which not only the mechanical properties but also the physical properties of 48 wood species were described. During the bulk of this period technical support was provided by Mr J.C. Verwijs and more recently by Mr L. van Brussel. After extensive studies, the Belgian Timber Information Institute also adopted the same research methods as TNO in order to obtain physical data on a number of wood species which were of commercial interest to the Belgian market but which had not been covered in TNO's studies. The Belgian Timber Information Institute's suggestion to include their research results, on a total of 17 wood species in this publication, .was therefore gratefully accepted."

Conifer Cold Hardiness provides an up-to-date synthesis by leading scientists in the study of the major physiological and environmental factors regulating cold hardiness of conifer tree species. This state-of-the-art reference comprehensively explains current understanding of conifer cold hardiness ranging from the gene to the globe and from the highly applied to the very basic. Topics addressed encompass cold hardiness from the perspectives of ecology, ecophysiology, acclimation and deacclimation, seedling production and reforestation, the impacts of biotic and abiotic factors, and methods for studying and analyzing cold hardiness. The content is relevant to geneticists, ecologists, stress physiologists, environmental and global change scientists, pathologists, advanced nursery and silvicultural practitioners, and graduate students involved in plant biology, plant physiology, horticulture and forestry with an interest in cold hardiness.

The increasing con'.;ern for the serious problems of forest decline that occurred in the Northern Hemisphere in the late 1970's and early 1980 's led to an emphasis on the necessity of promoting and setting up investigations into the basic physiological mechanisms of forest trees. Since then, the concern about rapid changes has decreased along with the increase of monitored data on European forests health status. But tree physiology has faced new questions about changing climate and increasing atmospheric carbon dioxide concentrations. Advances in plant molecular biology and forest genetics have opened up new avenues in the research on forest tree physiology. At the same, time it has become evident that molecular and genetic tools give only a basis for further research on tree structure and function, which needs basic tree physiology again. On the other hand, the problems of forest decline in Europe are not over. They are no longer discussed daily in the media, but stress is an everyday phenomenon experienced by European forest trees. For instance, in southern Europe and mountainous regions, drought stress and many other abiotic or biotic factors are stressors and cause problems to forests with many important social and protective functions. Stress physiology is a branch of everyday physiology in traditional forestry. How to grow a forest with maximal carbon binding functions and optimal wood quality and rich in biodiversity."

Large areas of the warm, humid tropics in Southeast Asia, the Pacific, Latin America, the Caribbean, and Africa are hilly or mountainous. Jackson and Scherr (1995) estimate that these tropical hillside areas are inhabited by 500 million people, or one-tenth of the current world population, many of whom practice subsistence agriculture. The region most affected is Asia which has the lowest area of arable land per capita. Aside from limited areas of irrigated terraces, most of the sloping land, which constitutes 60% to 90% of the land resources in many Southeast Asian countries, has been by-passed in the economic development of the region (Maglinao and Hashim, 1993). Poverty in these areas is often high, in contrast to the relative wealth of irri gated rice farms in lowland areas that benefited from the green revolution. Rapid population growth in some countries is also exacerbating the problems of hillside areas. Increasingly, people are migrating from high-potential lowland areas where land is scarce to more remote hillside areas. Such migra tion, together with inherent high population growth, is forcing a transforma tion in land use from subsistence to permanent agriculture on fragile slopes, and is creating a new suite of social, economic, and environmental problems (Garrity, 1993; Maglinao and Hashim, 1993)."

Reliability-based design (RBD) procedures for engineered structures are being developed and quickly gaining acceptance by cade agencies throughout the world. Numerous organizations are involved in the development of national or regional cades without the benefit of interchange of ideas and methodologies. Harmonization and coordination of these activities is absolutely essential if the ever-increasing international commerce is to flourish. This NATO Advanced Research Workshop (ARW) was organized to bring together, for the first time, experts on RBD and related subjects from various countries to assess the current knowledge and recommend new developments. Further, due to their unique nature and great economic significance in most parts of the world, special emphasis was placed on engineered wood structures. For example, in North America more wood products are used in construction than ali other materials (steel, concrete, brick, etc.) combined. However, the wood industry segment, historically, receives less attention and smaller financial support for new developments than other construction materials. RBD developments are being conducted in Similar, but largely independent, Europe, North America, New Zealand and Australia. Experts from these regions were brought together to exchange information on current work, propose new developments and to provide means of international coordination. Thus, this ARW provided an opportunity to advance the cause of RBD of engineered wood structures.

International climate change policy can be broadly divided into two periods: A first period, where a broad consensus was reached to tackle the risk of global warming in a coordinated global effort, and a second period, where this consensus was finally framed into a concrete policy. The first period started at the "Earth Summit" of Rio de Janeiro in 1992, where the United Nations Framework Convention on Climate Change (UNFCCC) was opened for signature. The UNFCCC was subsequently signed and ratified by 174 countries, making it one of the most accepted international rd treaties ever. The second period was initiated at the 3 Conference of the Parties (COP3) to the UNFCCC in Kyoto in 1997, which produced the Kyoto Protocol (KP). Till now, eighty-four countries have signed the Kyoto Protocol, but only twelve ratified it. A major reason for this slow ratification is that most operational details of the Kyoto Protocol were not decided in Kyoto but deferred to following conferences. This deferral of the details, while probably appropriate to initially reach an agreement, is a major stepping stone for a speedy ratification of the protocol. National policy makers and their constituencies, who would ultimately bear the cost of Kyoto, are generally not prepared to ratify a treaty that could mean anything, from an unsustainable strict regime of international control of greenhouse gases (GHGs) to an "L-regime" ofloopholes, or from a pure market-based international carbon trading to a regime of huge international carbon tax funds.

The impetus for this book was the desire to systematically organize the extant literature on the conservation of cultural property made of wood, from its beginnings before the Christian Era to the year 2000. Various published reviews and monographs, including Holzkonservierung (Wood Conserva tion) published by the senior author in 1988, have appeared over the years, especially in English and in German. They have provided exemplary treat merit of individual areas or aspects of wood conservation, but a comprehen sive, up-to-date exposition of historic and current developments has been lacking. The diverse professional fields of the authors, as well as their insights into methods of conservation and restoration of wood artifacts in Europe, North America, and Asia provided a solid basis for the success of this under taking. One of the goals during the examination of the literature was that not only well-known conservators and scientists from countries that are leaders in wood conservation should be represented, but that less well-known, often not as readily accessible contributions should also be included. Only in this manner was it possible to draw a comprehensive picture of the national and international state of wood conservation. The Art and Archaeology Technical Abstracts (AATA) of the Getty Institute were very helpful in our efforts to evaluate as many publications as possible."

The threats posed by air pollution and climate change have resulted in considerable public debate about forest condition and growth during the past two decades. Despite the massive input ofresearch resources, no clear answers have been found to these global questions. Although there have been substantial advances in our knowledge of the effects of air pollutants on the forests, many of the questions associated with forest condition are still open. Monitoring of forest condition at the national level started in Finland in 1985 in accordance with the methodology drawn up by the International Co-operative Programme on Assessments and Monitoring of Air Pollution Effects on Forests (ICP Forests, UN/ECE). Since then, research into forest condition and vitality has been one of the key areas in the research carried out by the Finnish Forest Research Institute. Three basic questions formed the starting point for the multidisciplinary, Forest Condition Research Programme: What changes are taking place in our forests? Why does forest condition vary, and why do trees appear to be suffering? How can forest condition be maintained through appropriate forest management? This report covers forest condition and changes in environmental factors on the of the latest findings, publications and expertise of researchers participated in basis the Forest Condition Research Programme. In addition to researchers from the Finnish Forest Research Institute, a large number of scientists from domestic and foreign universities and research institutes also made a considerable contribution to the research programme.

Bioenergy from Sustainable Forestry synthesizes information needed to design or implement sustainable forest management systems for production of biomass for energy in conjunction with other forest products. It is organized around the criteria for sustainable forest management: productivity, environment, social issues, economics, and legal and institutional framework. More than 25 international experts from 10 countries have brought together available ecological, physical, operational, social and economic information and identified gaps in knowledge related to biomass production and harvesting systems. This is the first time that such comprehensive information has been brought together under one cover, using an integrated, holistic approach. Guiding principles and state of the art knowledge are emphasized. The book will enable forest resource managers and planners to evaluate the ability of specific forest regions to sustainably meet bioenergy production demands.

The literature on the geology, chemistry, and biochemistry of phosphorus generally takes its mineralogy for granted. The in cidental information on phosphate minerals given in these texts is often obsolescent and inaccurate. The few mineralogical texts that have dealt comprehensively with the phosphate minerals have now become outdated, and typically present the essential information in a manner unsuitable for nongeological readers. This volume is intended as a ready reference for workers who require good basic information on phosphate minerals or their synthetic equivalents. The topics covered should appeal to geologists and geochemists, lithologists, environmental scientists and engineers, chemists and biochemists who have any interest in the intricate world of phosphorus. The hard tissues of many vertebrates and the many pathological calcifications consist mostly of phosphate minerals. The precipita tion of these compounds also plays a major role in the ecological cycling of phosphorus, and occasionally even dominates the behavior of many trace metals in many geochemical and biolog ical systems. Indeed, many pegmatitic phosphate minerals have acquired some notoriety because of the rarer trace metals which they tend to accumulate. With the commercialization of phosphate fertilizers since the early part of the 19th century, phosphate minerals have assumed an important role in industrial chemistry and agriculture. Clearly, the study of phosphate minerals is important from the economic, agricultural, environmental and (human and animal) health viewpoint."

The world population in 1950 was 2. 5 billion and is more than 5 billion today. The agriculture community, however, has responded remarkably well to meeting the increased need for food and fiber. While the population growth during this period averaged almost 2% annually, the production of grain increased at an even faster rate. From 1950 to 1973, grain production increased 3. 1% annually, but slowed to about 2% from 1973 to 1984. There fore, as a whole, the world has more grain per capita available today than ever before. Several countries that were food importers just a few years ago are food exporters today. The world carry-over stocks today are the highest in years. While the major concern just a few years ago was whether the world could produce adequate food, the problem for many countries today is how to export their surpluses. Although the world as a whole has surplus food supplies, there are millions of people without adequate food to exist, and there are additional millions who have a bare subsistence diet at best. The average daily calorie supply for the developed countries is more than 3,300 per person, while the average for the developing countries is only about 2,200. The major global food produc tion problems have shifted from Asia to Africa, where malnutrition, poverty, and starvation are attracting world attention."

The comparative study of mediterranean type ecosystems has gained considerable momentum during the past two decades. Modem studies on these systems date from the work of Ray Specht, who studied the dynamics of the heath vegetation of south ern Australia. The results of these studies first appeared in 1957 (Specht and Rayson, 1957) and were summarized in 1973 (Specht, 1973). Specht followed this detailed work, which pointed to the central role of nutrients in limiting the productivity of the Australian heath, with a general comparison of the structural features of woody plant communities in mediterranean type ecosystems of Australia, southern France, and southern California (Specht, 1969a, b). The comparative studies emphasized remark able convergent features of these ecosystems, particularly in relation to structural features affecting primary production. Naveh (l967) also did comparative studies focusing on grassland types that occur in the mediterranean climatic zones of Califor nia and IsraeL About this same time, independent studies by Mooney and Dunn (1970 a, b) and Mooney et al. (1970) made preliminary structural and functional comparisons of the vegetations of mediterranean type ecosystems in California and Chile in an at tempt to derive an evolutionary model explaining the basis of their convergent natures. Much of the knowledge of these ecosystems up to 1973 was summarized in volume 7 of Ecological Studies, Medite"anean Type Ecosystems: Origin and Structure (di Castri and Mooney, 1973). This volume builds on its series predecessor in many ways."

"Reviews of Environmental Contamination and Toxicology" contains timely review articles concerned with all aspects of chemical contaminants (including pesticides) in the total environment, including toxicological considerations and consequences. It attempts to provide concise, critical reviews of advances, philosophy, and significant areas of accomplished or needed endeavor in the total field of residues of these and other foreign chemicals in any segment of the environment, as well as toxicological implications.

"Reviews of Environmental Contamination and Toxicology" contains timely review articles concerned with all aspects of chemical contaminants (including pesticides) in the total environment, including toxicological considerations and consequences. It provides concise, critical reviews of advances, philosophy, and significant areas of accomplished or needed endeavor in the total field of residues of these and other foreign chemicals in any segment of the environment, as well as toxicological implications.

Five years have now passed since the first symposium on frankiae was held at Harvard Forest, Petersham, Massachusetts, USA and the inauguration of the term actinorhiza. Many advances have been made during these five years in our understanding of the actinorhizal symbioses. Evidence for this was provided by the papers presented at the Wageningen Workshop on Frankia symbioses, held in Wageningen at the Department of Microbiology of the Agricultural University. Most of these papers are now published in this volume of PLANT AND SOIL. We kindly acknowledge the assistance of Anton Houwers, editor of the journal, in planning, reviewing and publishing these studies. Although the papers presented at Wageningen described the active research areas, they also illuminated those aspects of these symbioses which remain beyond our understanding. Primary among the areas of our ignorance is the concept of species within the bacterial symbiont, Frankia. At present groupings of bacterial strains are based on cell chemistry, physiology, serology, DNA homology and symbiotic capa bilities (cross-inoculation). When these classification schemes are merged no clear species framework is obtained. Undoubtedly part of the difficulty is due to a lack of strains for analysis. Currently bacterial strains from only half of the actinorhizal symbioses known to exist, have been isolated and studied in pure culture. We must postpone there fore any comprehensive taxonomic classification until a larger majority of the symbioses are represented. Another research area wherein our understanding is insufficient is host-symbiont interaction."

This volume investigates how large herbivores not only influence the structure and distribution of the vegetation, but also affect nutrient flows and the responses of associated fauna. The mechanisms and processes underlying the herbivores' behavior, distribution, movement and direct impact on the vegetation are discussed in detail. It is shown that an understanding of plant/animal interactions can inform the management of large herbivores to integrate production and conservation in terrestrial systems.

This is a thorough study of photosynthetic mechanisms from cells to leaves, crown, and canopy. The authors question whether photosynthetic adaptations take place primarily at the metabolic and biochemical level or through changes in structure and form, or both. The text goes on to analyze the relative importance of genes that control metabolic and light reactions, and the structure, arrangement, and orientation of photosynthesis.

Mangroves are a fascinating group of plants that occur on tropical and subtropical shorelines of all continents, where they are exposed to saltwater inundation, low oxygen levels around their roots, high light and temperature conditions, and periodic tropical storms. Despite these harsh conditions, mangroves may form luxuriant forests which are of significant economic and environmental value throughout the world - they provide coastal protection and underpin fisheries and forestry operations, as well as a range of other human activities.

This book provides an up-to-date account of mangrove plants from around the world, together with silvicultural and restoration techniques, and the management requirements of these communities to ensure their sustainability and conservation.
All aspects of mangroves and their conservation are critically re-examined. Those activities which threaten their ongoing survival are identified and suggestions are offered to minimise their effects on these significant plant communities.

Tanzania is one of the most biologically diverse nations in the world. Traveling from west to east across Tanzania, one encounters an incredible array of ecosystems and species. Beginning at Lakes Victoria, Tanganyika, and Nyasa that form much of the western boundary of Tanzania, one finds the most diverse and some of the most spectacular concentrations of endemic fish in any of the world's lakes. Moving further inland from the lakes, one meets the woodlands and plains of Serengeti, Ngorongoro, Tarangire, and Lake Manyara. The assemblages and movements of large mammals in these protected areas are unparalleled worldwide. Traveling yet further to the east, one comes to Mount Kilimanjaro, the highest mountain in Africa. Mount Kilimanjaro is of sufficient height to not only contain seven major vegetation zones, but also maintain permanent glaciers. Finally, shortly before arriving at the Indian Ocean, one encounters the Eastern Arc Mountains, a series of isolated and geologically ancient mountains, which due to their height and proximity to the Indian Ocean intercept sufficient precipitation to support, in many areas, moist tropical forest. The Eastern Arc Mountains are among the richest sites biologically in all of Africa and harbor unusually high concentrations of endemic species - species whose geographic distribution are restricted to these mountains. Unfortunately, much of Tanzania's biodiversity is threatened by habitat alteration, destruction, and exploitation. The Eastern Arc forests face some of the most severe threats to any of Tanzania's biologically unique sites.