S.C. van de Geijn – författare

During the 4th ESA-Congress, held in the Netherlands, 7-11 July 1996, a new perspective for agronomy emerged. Various contributions demonstrate the need for a new role of agronomy and its tools. In recent decades, agriculture has evolved from an activity with mainly productivity aims, into an issue conciliating environmental, agricultural, and economic and social objectives. Placing agriculture in such a broadened perspective requires a different agronomy, with new tools and approaches at a range of aggregration levels. It calls for detailed knowledge concerning the functioning, productivity and ecological relationships of agricultural plants and crops. In addition, it calls for a constant update and synthesis of existing and newly generated knowledge, the design of new ideotypes and genotypes, new production technologies, cropping systems, farming systems and agro-ecological land use systems.This proceedings book presents a set of case studies illustrating the various agronomic tools that can be used for specific agronomic questions. The case studies are grouped in sections illustrating relevant subquestions in developing an agriculture with broadened objectives. The book starts with an introductory paper on the role of agronomy in research and education in Europe. The second section deals with agricultural land use, food security and environment. This is followed by a set of papers describing experimental research and modeling approaches used to design new ideotypes of crops, including physiological properties in relation to growth factors such as radiation, CO2, temperature and water.Sustained soil fertility directly links to nutrient cycling and soil organic matter. A selected set of papers addresses the improvements in resource use efficiency and as such their contribution towards economic, environmental and agricultural objectives. The final section addresses the design of integrated and ecological arable farming systems. It highlights the role of prototyping interaction with leading-edge farmers, as promising tools to design, implement and test new farming systems.It is hoped that the activities of the European Society for Agronomy and the Proceedings of its 4th Congress will stimulate to serve the new perspectives of agronomy, i.e. to adopt ecological principles, to optimally manage the use of resources and to meet social and economic objectives.

During the 4th ESA-Congress, held in the Netherlands, 7-11 July 1996, a new perspective for agronomy emerged. Various contributions demonstrate the need for a new role of agronomy and its tools. In recent decades, agriculture has evolved from an activity with mainly productivity aims, into an issue conciliating environmental, agricultural, and economic and social objectives. Placing agriculture in such a broadened perspective requires a different agronomy, with new tools and approaches at a range of aggregration levels. It calls for detailed knowledge concerning the functioning, productivity and ecological relationships of agricultural plants and crops. In addition, it calls for a constant update and synthesis of existing and newly generated knowledge, the design of new ideotypes and genotypes, new production technologies, cropping systems, farming systems and agro-ecological land use systems.

This proceedings book presents a set of case studies illustrating the various agronomic tools that can be used for specific agronomic questions. The case studies are grouped in sections illustrating relevant subquestions in developing an agriculture with broadened objectives. The book starts with an introductory paper on the role of agronomy in research and education in Europe. The second section deals with agricultural land use, food security and environment. This is followed by a set of papers describing experimental research and modeling approaches used to design new ideotypes of crops, including physiological properties in relation to growth factors such as radiation, CO2, temperature and water.

Sustained soil fertility directly links to nutrient cycling and soil organic matter. A selected set of papers addresses the improvements in resource use efficiency and as such their contribution towards economic, environmental and agricultural objectives. The final section addresses the design of integrated and ecological arable farming systems. It highlights the role of prototyping interaction with leading-edge farmers, as promising tools to design, implement and test new farming systems.

It is hoped that the activities of the European Society for Agronomy and the Proceedings of its 4th Congress will stimulate to serve the new perspectives of agronomy, i.e. to adopt ecological principles, to optimally manage the use of resources and to meet social and economic objectives.

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.

Why a New Handbook on Root Methods? Uptake of water and nutrients is a key process in agricultural and natural ecosystems. Plant roots play a vital role in the supply of resources for growth, and yet we have a relatively poor understanding of how they function in the natural soil environment. Dr. B6hm began the Preface of his standard text on root research methods (B6hm 1979) with the comment: "Root research under natural jield conditions is a step-child of science. The reason for this is primarily methodological. The known methods are tedious, time-consuming and the accuracy of their results is of ten not very great". Although improvements have been made recently for some methods, working on roots is stiH tedious and time-consuming. Compared to some other disci­ plines, a root researcher requires a considerable budget for his or her work. It is for this reason that in root research careful planning, the choice of appro­ priate methods and also a clear idea of which root characteristic should be observed in relation to the goal of the research question are fundamental. Con­ sequently, it is recommended to make use of "root experience" developed else­ where as much as possible.

Why a New Handbook on Root Methods? Uptake of water and nutrients is a key process in agricultural and natural ecosystems. Plant roots play a vital role in the supply of resources for growth, and yet we have a relatively poor understanding of how they function in the natural soil environment. Dr. B6hm began the Preface of his standard text on root research methods (B6hm 1979) with the comment: "Root research under natural jield conditions is a step-child of science. The reason for this is primarily methodological. The known methods are tedious, time-consuming and the accuracy of their results is of ten not very great". Although improvements have been made recently for some methods, working on roots is stiH tedious and time-consuming. Compared to some other disci­ plines, a root researcher requires a considerable budget for his or her work. It is for this reason that in root research careful planning, the choice of appro­ priate methods and also a clear idea of which root characteristic should be observed in relation to the goal of the research question are fundamental. Con­ sequently, it is recommended to make use of "root experience" developed else­ where as much as possible.

Why a New Handbook on Root Methods? Uptake of water and nutrients is a key process in agricultural and natural ecosystems. Plant roots play a vital role in the supply of resources for growth, and yet we have a relatively poor understanding of how they function in the natural soil environment. Dr. B6hm began the Preface of his standard text on root research methods (B6hm 1979) with the comment: "Root research under natural jield conditions is a step-child of science. The reason for this is primarily methodological. The known methods are tedious, time-consuming and the accuracy of their results is of ten not very great". Although improvements have been made recently for some methods, working on roots is stiH tedious and time-consuming. Compared to some other disci­ plines, a root researcher requires a considerable budget for his or her work. It is for this reason that in root research careful planning, the choice of appro­ priate methods and also a clear idea of which root characteristic should be observed in relation to the goal of the research question are fundamental. Con­ sequently, it is recommended to make use of "root experience" developed else­ where as much as possible.

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.

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.