This book presents the results of the Interdisciplinary Research Group "Society - Water - Technology" of the Berlin-Brandenburg Academy of Sciences and Humanities. It describes interdisciplinary evaluation criteria for major water engineering projects (MWEPs) and portrays an application to the Lower Jordan Valley (Middle East) and the Fergana Valley (Central Asia). Both areas are characterised by transboundary conflicts, by challenges due to demographic and climate change and by political and societal pressures. Based on the findings, the book provides recommendations for science and political decisions makers as well as for international financing institutions. In addition, it outlines research gaps from an interdisciplinary perspective. In the past, MWEPs have been used as an instrument to cope with the demands of growing populations and to enhance development progress. Experiences with MWEPs have shown that a purely technical approach has not always brought about the desired results. In many cases, MWEPs have even resulted in negative implications for society and environment. Therefore, improved management strategies and enhanced technologies for a sustainable water resource management system are a prerequisite to meet present and future challenges. And, moreover, the continuous evaluation and optimisation of these measures is, likewise, a must.

Human activities are significantly modifying the natural global carbon (C) cycles, and concomitantly influence climate, ecosystems, and state and function of the Earth system. Ever increasing amounts of carbon dioxide (CO2) are added to the atmosphere by fossil fuel combustion but the biosphere is a potential C sink. Thus, a comprehensive understanding of C cycling in the biosphere is crucial for identifying and managing biospheric C sinks. Ecosystems with large C stocks which must be protected and sustainably managed are wetlands, peatlands, tropical rainforests, tropical savannas, grasslands, degraded/desertified lands, agricultural lands, and urban lands. However, land-based sinks require long-term management and a protection strategy because C stocks grow with a progressive improvement in ecosystem health.

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.

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 special volume contains papers that are partly based on contributions to the symposium "Minesite Recultivation" wh ich was held at the Brandenburg Technical University in Cottbus, FRG in lune 1994. Ouring this symposium, various aspects of research into the recultivation of open-cast minesites were discussed. As a prime example, the symposium focussed on the recultivation (reclamation) of post-mining landscapes in the Lusatian lignite mining district of the former German 2 Oemocratic Republic (GOR). In this area, about 700 km have been devastated by open- cast mining during the last 70 years. Therefore, the research into recultivation has a long tradition in Lusatia, going back to the 1930's. Oue [0 the scientific isolation of the former GOR, most of the research results were not available to an international audience until now. This situation holds also true for other eastern countries. Hence, this special volume is a first step to fill this gap. The papers by Pietsch, Heinsdorf, and Katzur and Haubold-Rosar detail the Lusatian lignite mining district presenting an overview of recultivation research results and practical experiences related to the establishment of terrestrial and aquatic ecosystems in this region after mining. In particular, the amelioration and reforestation of extremely acid, sulfurous mine soils, the fertilization of forest stands under different mine site conditions and the site-specific recolonization and re vegetation strategies are described.

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 special volume contains papers that are partly based on contributions to the symposium "Minesite Recultivation" wh ich was held at the Brandenburg Technical University in Cottbus, FRG in lune 1994. Ouring this symposium, various aspects of research into the recultivation of open-cast minesites were discussed. As a prime example, the symposium focussed on the recultivation (reclamation) of post-mining landscapes in the Lusatian lignite mining district of the former German 2 Oemocratic Republic (GOR). In this area, about 700 km have been devastated by open- cast mining during the last 70 years. Therefore, the research into recultivation has a long tradition in Lusatia, going back to the 1930's. Oue [0 the scientific isolation of the former GOR, most of the research results were not available to an international audience until now. This situation holds also true for other eastern countries. Hence, this special volume is a first step to fill this gap. The papers by Pietsch, Heinsdorf, and Katzur and Haubold-Rosar detail the Lusatian lignite mining district presenting an overview of recultivation research results and practical experiences related to the establishment of terrestrial and aquatic ecosystems in this region after mining. In particular, the amelioration and reforestation of extremely acid, sulfurous mine soils, the fertilization of forest stands under different mine site conditions and the site-specific recolonization and re vegetation strategies are described.

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.

Human activities are significantly modifying the natural global carbon (C) cycles, and concomitantly influence climate, ecosystems, and state and function of the Earth system. Ever increasing amounts of carbon dioxide (CO2) are added to the atmosphere by fossil fuel combustion but the biosphere is a potential C sink. Thus, a comprehensive understanding of C cycling in the biosphere is crucial for identifying and managing biospheric C sinks. Ecosystems with large C stocks which must be protected and sustainably managed are wetlands, peatlands, tropical rainforests, tropical savannas, grasslands, degraded/desertified lands, agricultural lands, and urban lands. However, land-based sinks require long-term management and a protection strategy because C stocks grow with a progressive improvement in ecosystem health.

In dem Band werden die Auswirkungen des globalen Wandels hinsichtlich der Nutzung der Ressourcen Wasser und Boden analysiert und moegliche Anpassungsstrategien diskutiert. Auch wenn diese Fragen am Beispiel der Region Berlin-Brandenburg untersucht werden, haben die Autoren ihre Analysen und Empfehlungen bewusst so ausgestaltet, dass sie auf vergleichbare Regionen ubertragen werden koennen. Mit ihrer interdisziplinaren Perspektive bietet diese Untersuchung eine erste Orientierung fur die Entwicklung geeigneter Anpassungsstrategien.

Periphere landliche Raume sehen sich einer zunehmenden Abwanderung und Alterung der Bevolkerung sowie wirtschaftlicher Stagnation ausgesetzt. Gleichzeitig nimmt jedoch die Nachfrage nach den naturlichen Ressourcen landlicher Raume immer starker zu, was sich z. B. in steigenden Preisen fur Bodenflache und Agrarrohstoffe, aber auch in der wachsenden Wertschatzung von Umweltleistungen aussert. In dem Buch werden nach einer Einfuhrung in die Entwicklungsdynamik landlicher Raume Szenarien fur eine Landnutzung entworfen, die mehr als bisher an gesellschaftlicher Nachfrage und Werten orientiert ist. Im Mittelpunkt des von der interdisziplinaren Arbeitsgruppe LandInnovation der Berlin-Brandenburgischen Akademie der Wissenschaften erarbeiteten Forschungsberichtes stehen funf mogliche Innovationsfelder einer zukunftsorientierten Landnutzung, die exemplarisch fur die landlichen Raume Nordostdeutschlands entwickelt werden, zugleich jedoch auch fur andere periphere Regionen von Relevanz sind: - die energetische und stoffliche Nutzung nachwachsender Rohstoffe, - Viehhaltung in standortangepassten Intensitaten, - der Anbau von Pflanzen mit neuartigen Eigenschaften, - Lebensqualitat und Infrastruktur in den Bereichen Mobilitat, Schulbildung, Gesundheit und Pflege sowie - der Aufbau von Markten fur okologische Leistungen."