Jelte Rozema – författare

An international workshop on "CO2 and Biosphere" was held in Wageningen, The Netherlands on 15-19 November, 1991 as part of the activities of the CO2 Commission of the Netherlands Organization for Scientific Research: this volume includes 32 papers presented at the workshop. The CO2 Commission stimulates and coordinates a broad range of research projects related to the greenhouse effect. This is reflected in the scope of papers presented, ranging from detailed analyses of ecological and physiological effects of atmospheric CO2 enrichment to biosphere-atmosphere aspects, such as regional evaporation, energy balance and ecosystem responses. Relevant directions for future research are indicated by presentations on carbon fluxes in the soil, secondary plant metabolism and plant - insect interactions.

Current phase-out schedules of the production and emission of CFC's indicate that chlorine loading in the stratosphere is not yet at its maximum. The recovery of stratospheric ozone is estimated to take time and ele­ vated levels of UV-B radiation are expected to occur throughout most of the next century. Despite numerous physiological studies of UV-B effects on plants, often grown in climate chambers, knowledge of UV-B effects on organisms and processes in natural aquatic or terrestrial ecosystems is poor. Currently it appears that UV-B radiation is not just an environmental stress' factor to plants. In various ways, which are incompletely understood, UV-B affects a wide range of physiological and ecological processes. Remarkably, recent field studies indicate that enhanced UV-B does not markedly affect photosynthesis, growth and primary production, but rather interferes with plant morphogenesis and plant and ecosystem functions relating to the secondary metabolism. This special issue and book UV-B and Biosphere is an attempt to cover this range and to report the progress made in the research of ecological effects of enhanced solar UV-B radiation. The papers in this book formed the basis of an international workshop entitled' UV-B and Biosphere' , December 15-18, 1995, in Wageningen, The Netherlands. A first reaction of Hans de Boois on the number of papers and sessions scheduled from Friday to Sunday morning was: far too many.

The research in this book covers papers on a great number of research projects on the responses of plants and crops of natural terrestrial ecosystems, of agro-ecosystems, and of aquatic ecosystems, to enhanced solar UV-B as a result of stratospheric ozone depletion. Some introductory chapters deal with general aspects of how plants respond to UV-B radiation. Photosynthetically Active Radiation (PAR) is a primary energy resource for terrestrial plants, necessary for plant growth. Inevitably terrestrial plants absorb UV-B when exposed to solar radiation. The spectral balance between PAR and UV-B is discussed in several chapters. The responses of plants and ecosystems from the Antarctic and Arctic to enhanced solar UV-B radiation as a consequence of the hole in the ozone layer are considered in some detail. In addition the papers in the book discuss the problem of how responses of plants to UV-B radiation interact with other environmental factors.

Plants and Climate Change focuses on how climate affects or affected the biosphere and vice versa both in the present and past. The chapters describe how ecosystems from the Antarctic and Arctic and from other latitudes respond to global climate change.The papers highlight plant responses to atmospheric CO2 increase, to global warming and to increased ultraviolet-B radiation as a result of stratospheric ozone depletion.Depending on how and how well plant responses to increased temperature, atmospheric CO2 and ultraviolet-B have been preserved in the (sub)-fossil record, past climates and past atmospheric chemistry may be reconstructed. Pollen and tree-ring data reflect plant species composition and variation of temperature and precipitation over long or shorter time intervals. In addition to well preserved morphological and chemical plant properties, new analytical techniques such as stable isotopes are becoming increasingly important in this respect. The development and validation of such biotic climate and environment proxies build a bridge between biological and geological research. This highlights that plant-climate change research is becoming a multi- and transdisciplinary field of relevant research.

The research in this book covers papers on a great number of research projects on the responses of plants and crops of natural terrestrial ecosystems, of agro-ecosystems, and of aquatic ecosystems, to enhanced solar UV-B as a result of stratospheric ozone depletion. Some introductory chapters deal with general aspects of how plants respond to UV-B radiation. Photosynthetically Active Radiation (PAR) is a primary energy resource for terrestrial plants, necessary for plant growth. Inevitably terrestrial plants absorb UV-B when exposed to solar radiation. The spectral balance between PAR and UV-B is discussed in several chapters. The responses of plants and ecosystems from the Antarctic and Arctic to enhanced solar UV-B radiation as a consequence of the hole in the ozone layer are considered in some detail. In addition the papers in the book discuss the problem of how responses of plants to UV-B radiation interact with other environmental factors. The book is of great importance for those who are involved in global change topics: biologists, ecologists, earth scientists, agronomists, environmental scientists, and those who develop environmental policy.

Plants and Climate Change focuses on how climate affects or affected the biosphere and vice versa both in the present and past. The chapters describe how ecosystems from the Antarctic and Arctic and from other latitudes respond to global climate change.The papers highlight plant responses to atmospheric CO2 increase, to global warming and to increased ultraviolet-B radiation as a result of stratospheric ozone depletion.Depending on how and how well plant responses to increased temperature, atmospheric CO2 and ultraviolet-B have been preserved in the (sub)-fossil record, past climates and past atmospheric chemistry may be reconstructed. Pollen and tree-ring data reflect plant species composition and variation of temperature and precipitation over long or shorter time intervals. In addition to well preserved morphological and chemical plant properties, new analytical techniques such as stable isotopes are becoming increasingly important in this respect. The development and validation of such biotic climate and environment proxies build a bridge between biological and geological research. This highlights that plant-climate change research is becoming a multi- and transdisciplinary field of relevant research.

This book is the result of a symposium dedicated to the 25th anniversary of the Delta Institute for Hydrobiological Research in Yerseke, the Netherlands. The primary idea did not come from one of the scientists working in this Institute, but from the second editor. Long before the Institute celebrated itsjubilee on 20-23 October 1982, he expressed his feelings to the other editors, that the time had come for a second European symposium on the ecology of coastal vegetation. The first symposium on this theme was held in Norwich, 12-16 September 1977, being the first meeting of the European Ecological Symposium. He only So the working group Salt waited for a suitable opportunity. Well, the 25th anniversary was a good one. Marsh Ecosystems of the Delta Institute, in close collaboration with him, adopted Dr. Rozema's initiative and set about realizing his idea. An organising committee composed of the editors of this volume, planned the scope of the meeting.

An international workshop on `CO2 and Biosphere' was held in Wageningen, the Netherlands on 15-19 November 1991 as part of the activities of the CO2 Commission of the Netherlands Organization for Scientific Research: this volume includes 32 papers presented at the workshop. The CO2 Commission stimulates and coordinates a broad range of research projects related to the greenhouse effect. This is reflected in the scope of papers presented, ranging from detailed analyses of ecological and physiological effects of atmospheric CO2 enrichment to biosphere-atmosphere aspects, such as regional evaporation, energy balance and ecosystem responses. Relevant directions for future research are indicated by presentations on carbon fluxes in the soil, secondary plant metabolism and plant-insect interactions.

Current phase-out schedules of the production and emission of CFC's indicate that chlorine loading in the stratosphere is not yet at its maximum. The recovery of stratospheric ozone is estimated to take time and ele­ vated levels of UV-B radiation are expected to occur throughout most of the next century. Despite numerous physiological studies of UV-B effects on plants, often grown in climate chambers, knowledge of UV-B effects on organisms and processes in natural aquatic or terrestrial ecosystems is poor. Currently it appears that UV-B radiation is not just an environmental stress' factor to plants. In various ways, which are incompletely understood, UV-B affects a wide range of physiological and ecological processes. Remarkably, recent field studies indicate that enhanced UV-B does not markedly affect photosynthesis, growth and primary production, but rather interferes with plant morphogenesis and plant and ecosystem functions relating to the secondary metabolism. This special issue and book UV-B and Biosphere is an attempt to cover this range and to report the progress made in the research of ecological effects of enhanced solar UV-B radiation. The papers in this book formed the basis of an international workshop entitled' UV-B and Biosphere' , December 15-18, 1995, in Wageningen, The Netherlands. A first reaction of Hans de Boois on the number of papers and sessions scheduled from Friday to Sunday morning was: far too many.

September 1987, the Faculty Biology of the Vrije Universiteit, Amsterdam commemorated the fact that Prof. Dr. Wilfried Hans Otto Ernst had been active as a scientist for 25 years. This period of 25 years of scientific research started at the Institut flir Angewandte Botanik (Institute of Applied Botany) of the University of Munster, FRG. In 1965 he completed his Ph. D. thesis, entitled "Untersuchungen der Schwermetallpflanzengesellschaften Mitteleuropas unter Einschluss der Alpen. " He was appointed full Professor at the Department of Ecology of the Vrije Universiteit, Amsterdam in 1973. On the occasion of his 25th anniversary as a scientist, a promise was made, though in covert terms, which we could not redeem at that time. The promise held to offer Prof. Ernst a book, in which his former and present staffmembers, Ph. D. students and colle ages should write a review about their specialism concerning a central theme. Now, at the beginning of 1990 we consider the chapters of "Ecological Responses to Environmental Stresses" to be completed. The book reflects the wide range of research approaches that has been initiated and organized by Wilfried Ernst. The editors hope to have attained the primary aim of the production of the book of friends, that is to gather relevant papers of staff-members and colleagues of Wilfried Ernst. The title of the book "Ecological Responses to Environmental Stresses" covers the majority of the chapters included.