R. F. HUTTL AND W. SCHAAF Brandenburg Technical University Cottbus, Chair of Soil Protection and Recultivation, P.O. Box 10 13 44, 03013 Cottbus, Germany The health status of forest trees and stands is determined by numerous site factors such as chemical, physical, and biological soil factors, water supply, climate, weather conditions, management history as well as atmospheric deposition impacts. In this context, the nutrient supply is an important evaluation parameter. Forest trees well supplied with nutrients are more resistant to stresses that affect the forest ecosystem than other trees. This is true for both biotic and abiotic influences. Therefore the investigation of the so-called 'new type forest damage' was aimed at the exact determination of the health status of damaged trees. When considering the complete forest ecosystem, health (=vitality) means the sustainable ability to withstand negative environmental influences and still remain stable and productive. From this viewpoint, an optimal nutritional status is a prerequisite for an optimal health status. The term 'new type forest damage' comprises a number of damage symptoms which have been observed in various tree species on very different sites since the mid-1970s, particularly in Europe and North America. However, they occurred much more intensively in the 1980s. Generally, this forest damage was thought to be related to negative impacts of air pollutants.

From the research results and discussions presented in this book it becomes clear that a profound understanding of the various interrelationships of the nutritional aspects allows the implementation of specific management strategies to improve stability and productivity of forest ecosystems. In particular the effects of environmental changes as related to the impacts of air pollution, global change and land use on nutrient uptake and cycling processes in forest ecosystems are dealt with in detail. The book is divided into six main issues and each topic contains reviews as well as selected results of recent studies.

Situating forests in the context of larger landscapes, they reveal the complex patterns and processes observed in tree-dominated habitats. The updated and expanded second edition covers; Conservation; Ecosystem services; Climate change; Vegetation classification; Disturbance; Species interactions; Self-thinning; Genetics; Soil influences; Productivity; Biogeochemical cycling; Mineralization; Effects of herbivory; Ecosystem stability

This book arises out of a symposium on forest and woodland terrestrial ecosystems which was held in Florence on 20-24th May 1991. It was organised jointly by the Commission of the European Communities (CEC) and the European Science Foundation (ESF) in association with the Italian Research Council (CNR). The symposium brQughUogether most -Of the internationally recognized groups working on forest ecosystems including biologists, botanists, ecologists, soil scientists, modellers, foresters and policy makers. All the CEC countries were represented. In addition, there was a broad audience from Eastern and Central Europe and from EFfA countries. Outstanding experts from outside Europe (US, Australia, Canada, Japan, China, etc.) were also present. In total, the symposium was attended by more than 500 participants. The structure of this book reflects the main elements of the meeting. As such it includes three main sections. The first consists of six major state-of-the-art reviews corresponding to the six plenary sessions, each followed by a discussion which has been summarized by rapporteurs. The reviews were prepared to assess critically the state of current knowledge in ecosystem research and to provide a scientific basis both for policy decisions and for further research.

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 handbook in two volumes synthesises our knowledge about the ecology of Central Europe’s plant cover with its 7000-yr history of human impact, covering Germany, Poland, the Netherlands, Belgium, Luxembourg, Switzerland, Austria, Czech Republic and Slovakia. Based on a thorough literature review with 5500 cited references and nearly 1000 figures and tables, the two books review in 26 chapters all major natural and man-made vegetation types with their climatic and edaphic influences, the structure and dynamics of their communities, the ecophysiology of important plant species, and key aspects of ecosystem functioning. Volume I deals with the forests and scrub vegetation and analyses the ecology of Central Europe’s tree flora, whilst Volume II is dedicated to the non-forest vegetation covering mires, grasslands, heaths, alpine habitats and urban vegetation. The consequences of over-use, pollution and recent climate change over the last century are explored and conservation issues addressed.

Forest ecosystems represent a major type ofland use in Germanyand in Europe. They provide a number of functions, or ecosystem services, beneficial to humans, namely biomass production, regulation of the water- and energy cyde, C and N sequestration, erosion control, recreation, and they act as habitat for numerous species. The stability of forest ecosystems in Europe as influenced by the deposition of air pollutants has been a matter of debate for more than 20 years. Besides atmospheric deposition, other environmental conditions affecting forest ecosystems, such as temperature, CO content of the atmosphere 2 and precipitation, have significantly changed in the past and continue to change in the future. Quantifying and predicting the effects of these changes on ecosys tem functioning are achallenge to ecosystem research and also a requirement to establish sustainable use of forest ecosystems in the future. This book summarizes results of long-term, interdisciplinary ecosystem research conducted in two forested catchments and coordinated at the Bayreuth Institute of Terrestrial Ecosystem Research (BITÖK), University of Bayreuth, Germany. It does not aim to summarize all the research of BITÖ K in the past decade, which would go far beyond the studies in these two catch ments. Instead, we concentrate here on the long-term developments in the biogeochemistry of carbon and mineral elements and on the water cyde, at both the plot and the catchment scale.

T. C. Hutchinson The NATO Advanced Research Workshop detailed in this volume was held in Toronto, Canada, in 1985. The purpose of the Workshop was to provide a "state of the art" report on our knowledge of the sensitivities and responses of forests, wetlands and crops to airborne pollutants. Approximately 40 scientific experts from nine countries participated. Most participants were actively involved in research concerning the effects of air pollutants on natural or agro-ecosystems. These pollutants included acidic deposition, heavy metal particulates, sulphur dioxide, ozone, nitrogen oxides, acid fogs and mixtures of these. Also invited were experts on various types of ecosystem stresses, physiologi cal mechanisms pertinent to acid deposition, and other areas that were felt by the director to be of direct relevance, including: effects of ethylene on vegetation, the physiology of drought in trees, the nature and role of plant cuticles as barriers to acid rain penetration, the use of dendrochronological techniques in reconstructing the time of onset and the subsequent progression of growth declines, the ability of soils to naturally generate acidity, the role of Sphagnum moss in natural peat land acidity, the use of lichens as indicators of changing air quality, and the magnitude of natural emissions of reduced sulphur gases from tropical rainforests and temperate deciduous forests. The Workshop included a series of invited presentations and subsequent group discussions. These presentations were designed to allow syntheses of our present knowledge as well as detailed questioning and discussion.