Nutrients in Ecosystems – serie

The importance of magnesium in the element cycling of forest ecosystems has only been fully recognized since the widespread symptoms of forest magnesium deficiency were identified to be a major component in the damage phenomena. The intensive research during the last 15 years revealed not only details on the role of magnesium as a nutrient in forest ecosystems, but led also to a more comprehensive understanding of these ecosystems themselves and their functioning. This book tries to summarize the knowledge of magnesium and its role in forest ecosystems gathered from recent studies as well as from historical experiences and findings. The results of these studies in most cases point to the activity of man and his influence on the ecosphere. Therefore, when we understand the processes and effects described in this book, perhaps we can learn not only about a single nutrient like magnesium and forest ecosystems but also about ourselves.

Sulphur as an essential plant nutrient has received little attention. This is explained by the facts that sulphur was obviously in sufficient supply from the atmosphere, from soil and as a by-product in mineral fertilizers. Increases in the yield potential and thus in the nutrient requirement of modern crops, however, as well as remarkable changes in SO2 emissions by private households, power stations and industry, associated with legislative measures to reduce air and water pollution, have altered the situation to a large extent. In particular the public concerns about forest decline and pollution-induced climatic changes have initiated extensive research programs on the physiological functions of sulphur in plants, on the occurrence and plant availability of sulphur in agricultural and forest soils and on the chemistry of sulphur compounds in the tropo- and stratosphere. This text cannot be an encylcopedia of sulphur in all the media mentioned nor in all ecozones of the globe. However, it aims to give an overview of our present knowledge with a special focus on the sulphur situation in agrosystems of industrialised Western Europe.The ecological trends for sulphur observed in this region during recent decades are likely to be mirrored wherever industrialization and urbanization takes place and where an increasing standard of living demands clean air, good drinking water and nutritious food. Agricultural production systems, therefore, require well-founded information on the actual sulphur nutrition and potential sulphur-fertilizer requirement of crops and soils respectively. It is hoped that this book will provide this information and will encourage further research where open questions still exist.

This volume summarises the result of an interdisciplinary research programme entitled "Rehabilitation of the Atmosphere of the New States of Germany - Effects on Terrestrial Ecosystems". Before the unification of Germany, emission loads of SO2 and dust particles were up to 18-fold higher in East than in West Germany. However, emission rates have decreased significantly since reunification in 1990, due to the breakdown of a large number of industrial and particularly lignite-fired powerplants and the implementation of clean air technologies. In order to study the effects of these dramatic changes in atmospheric chemistry on terrestrial ecosystems, comprehensive field studies were conducted in pine forest ecosystems along an historic gradient of atmospheric deposition rates in the northeastern lowlands of Germany. The fast and dramatic reduction of dust particle and SO2 emissions offers a unique opportunity to test the role of SO2 and alkaline particle deposition with regard to changes or damage to forest ecosystems and whether the forest stands return to a state of resilience.

This volume summarises the result of an interdisciplinary research programme entitled `Rehabilitation of the Atmosphere of the New States of Germany - Effects on Terrestrial Ecosystems'. Before the unification of Germany, emission loads of SO2 and dust particles were up to 18-fold higher in East than in West Germany. However, emission rates have decreased significantly since reunification in 1990, due to the breakdown of a large number of industrial and particularly lignite- fired powerplants and the implementation of clean air technologies. In order to study the effects of these dramatic changes in atmospheric chemistry on terrestrial ecosystems, comprehensive field studies were conducted in pine forest ecosystems along an historic gradient of atmospheric deposition rates in the northeastern lowlands of Germany. The fast and dramatic reduction of dust particle and SO2 emissions offers a unique opportunity to test the role of SO2 and alkaline particle deposition with regard to changes or damage to forest ecosystems and whether the forest stands return to a state of resilience. In this respect, this ecosystem experiment can be looked upon as a roof experiment without a roof.

This is the second volume in the series Nutrients in Ecosystems. Sulphur as an essential plant nutrient has received little attention. This is explained by the facts that sulphur was obviously in sufficient supply from the atmosphere, from soil and as a by-product in mineral fertilizers. Increases in the yield potential and thus in the nutrient requirement of modern crops, however, as well as remarkable changes in SO2 emissions by private households, power stations and industry, associated with legislative measures to reduce air and water pollution, have altered the situation to a large extent. In particular the public concerns about forest decline and pollution-induced climatic changes have initiated extensive research programs on the physiological functions of sulphur in plants, on the occurrence and plant availability of sulphur in agricultural and forest soils and on the chemistry of sulphur compounds in the tropo- and stratosphere. This book cannot be an encylcopedia of sulphur in all the media mentioned nor in all ecozones of the globe. However, it aims to give an overview of our present knowledge with a special focus on the sulphur situation in agrosystems of industrialised Western Europe. The ecological trends for sulphur observed in this region during recent decades are likely to be mirrored wherever industrialisation and urbanisation take place and where an increasing standard of living demands clean air, good drinking water and nutritious food. Agricultural production systems, therefore, require well-founded information on the actual sulphur nutrition and potential sulphur-fertilizer requirement of crops and soils respectively. It is hoped that this book will provide this information and will encourage further research where open questions still exist.