R.H. Whittaker – författare

The period since World War II, and especially the last decade influenced by the International Biological Program, has seen enormous growth in research on the function of ecosystems. The same period has seen an exponential'' rise in environmental problems including the capacity of the Earth to support man''s population. The concern extends to man''s effects on the "biosphere"-the film of living organisms on the Earth''s surface that supports man. The common theme of ecologic research and environmental concerns is primary production­ the binding of sunlight energy into organic matter by plants that supports all life. Many results from the IBP remain to be synthesized, but enough data are available from that program and other research to develop a convincing sum­ mary of the primary production of the biosphere-the purpose of this book. The book had its origin in the parallel interests of the two editors and Gene E. Likens, which led them to prepare a symposium on the topic at the Second Biological Congress of the American Institute of Biological Sciences in Miami, Florida, October 24, 1971. Revisions of the papers presented at that symposium appear as Chapters 2, 8, 9, 10, and 15 in this book. We have added other chapters that complement this core; these include discussion and evaluation of methods for measuring productivity and regional production, current findings on tropical productivity, and models of primary productivity.

The period since World War II, and especially the last decade influenced by the International Biological Program, has seen enormous growth in research on the function of ecosystems. The same period has seen an exponential' rise in environmental problems including the capacity of the Earth to support man's population. The concern extends to man's effects on the "biosphere"-the film of living organisms on the Earth's surface that supports man. The common theme of ecologic research and environmental concerns is primary production­ the binding of sunlight energy into organic matter by plants that supports all life. Many results from the IBP remain to be synthesized, but enough data are available from that program and other research to develop a convincing sum­ mary of the primary production of the biosphere-the purpose of this book. The book had its origin in the parallel interests of the two editors and Gene E. Likens, which led them to prepare a symposium on the topic at the Second Biological Congress of the American Institute of Biological Sciences in Miami, Florida, October 24, 1971. Revisions of the papers presented at that symposium appear as Chapters 2, 8, 9, 10, and 15 in this book. We have added other chapters that complement this core; these include discussion and evaluation of methods for measuring productivity and regional production, current findings on tropical productivity, and models of primary productivity.

A large part of ecological research depends on use of two ap­ proaches to synthesizing information about natural communities: classification of communities (or samples representing these) into groups, and ordination (or arrangement) of samples in relation to environmental variables. A book published in 1973, 'Ordination and Classification of Communities,' sought to provide, through contributions by an international panel of authors, a coherent treatise on these methods. The book appeared then as Volume 5 of the Handbook of Vegetation Science, for which R. TuxEN is general editor. The desire to make this work more widely available in a less expensive form is one of the reasons for this second edition separating the articles on ordinction and on classification into two volumes. The other reason is the rapid advancement of understanding in the area of indirect ordination-mathematical techniques that seek to use measurements of samples from natural communities to produce arrangements that reveal environmental relationships of these communities. Such is the rate of change in this area that the last chapter on ordination in the first edition is already, 4 or 5 years after it was written, out of date; and new techniques of indirect ordination that could only be mentioned as possibilities in the first edition are becoming prominent in the field. In preparing the second edition the chapter on evaluation of ordinations has been rewritten, a new chapter on recent developments in continuous multivariate techniques has been included, and references to recent work have been added to other chapters.

The natural communities of the world are diverse, and many schools of ecology have developed classifications of communities in partial independence of one another. There is consequently a vast and widely dispersed literature on the classification of plant and animal communities, comprising divergent approaches of different schools and representing a great experiment on the usefulness of different possibilities for classification. The editor sought in a re­ view monograph of 1962 to summarize these schools and their history, and in 1973 published a treatise on 'Ordination and Clas­ sification of Communities' as volume 5 of the Handbook of Vegetation Science. We were fortunate, in preparing the latter work, to have a truly international panel of authors to discuss different major ap­ proaches to classification. This second edition of the book of 1973 is intended to make the work more widely available in a less expensive form as companion volumes on ordination and on classification of plant communities.

A large part of ecological research depends on use of two ap­ proaches to synthesizing information about natural communities: classification of communities (or samples representing these) into groups, and ordination (or arrangement) of samples in relation to environmental variables. A book published in 1973, ''Ordination and Classification of Communities,'' sought to provide, through contributions by an international panel of authors, a coherent treatise on these methods. The book appeared then as Volume 5 of the Handbook of Vegetation Science, for which R. TuxEN is general editor. The desire to make this work more widely available in a less expensive form is one of the reasons for this second edition separating the articles on ordinction and on classification into two volumes. The other reason is the rapid advancement of understanding in the area of indirect ordination-mathematical techniques that seek to use measurements of samples from natural communities to produce arrangements that reveal environmental relationships of these communities. Such is the rate of change in this area that the last chapter on ordination in the first edition is already, 4 or 5 years after it was written, out of date; and new techniques of indirect ordination that could only be mentioned as possibilities in the first edition are becoming prominent in the field. In preparing the second edition the chapter on evaluation of ordinations has been rewritten, a new chapter on recent developments in continuous multivariate techniques has been included, and references to recent work have been added to other chapters.

The natural communities of the world are diverse, and many schools of ecology have developed classifications of communities in partial independence of one another. There is consequently a vast and widely dispersed literature on the classification of plant and animal communities, comprising divergent approaches of different schools and representing a great experiment on the usefulness of different possibilities for classification. The editor sought in a re­ view monograph of 1962 to summarize these schools and their history, and in 1973 published a treatise on ''Ordination and Clas­ sification of Communities'' as volume 5 of the Handbook of Vegetation Science. We were fortunate, in preparing the latter work, to have a truly international panel of authors to discuss different major ap­ proaches to classification. This second edition of the book of 1973 is intended to make the work more widely available in a less expensive form as companion volumes on ordination and on classification of plant communities.