InhaltsangabeA Introduction to the European Transect.- 1 The Carbon and Nitrogen Cycle of Forest Ecosystems.- 1.1 Introduction.- 1.2 The Carbon and Nitrogen Cycles.- 1.3 The NIPHYS/CANIF Project.- 1.4 Experimental Design.- 1.5 Conclusions.- References.- 2 Experimental Sites in the NIPHYS/CANIF Project.- 2.1 Site Description. The NIPHYS/CANIF Transect.- 2.2 Soil Characteristics.- 2.3 Ecosystem C and N Pools.- 2.4 Database.- 2.5 Conclusions.- References.- B Plant-Related Processes.- 3 Tree Biomass, Growth and Nutrient Pools.- 3.1 Introduction.- 3.2 Experimental Background.- 3.3 Biomass.- 3.4 Forest Productivity.- 3.5 Carbon and Nutrient Pools.- 3.6 Allometric and Functional Relations.- 3.7 Conclusion.- References.- 4 Linking Plant Nutrition and Ecosystem Processes.- 4.1 Introduction.- 4.2 Experimental Approach.- 4.3 Nutrient Concentrations.- 4.4 Nutrient Contents.- 4.5 Nitrogen Partitioning in Different Tree Compartments.- 4.6 Ecosystem C and N Pools.- 4.7 Conclusions.- References.- 5 Root Growth and Response to Nitrogen.- 5.1 Introduction.- 5.2 Approaches to the Study of Root Growth.- 5.3 Root Growth Measurements Obtained by Soil Coring.- 5.4 Root Growth Measurements Obtained by Root Windows.- 5.5 Root Growth Measurements Obtained by In-Growth Cores.- 5.6 Root Growth at Different European Forest Sites.- 5.7 Conclusion.- References.- 6 Nitrogen Uptake Processes in Roots and Mycorrhizas.- 6.1 Introduction.- 6.2 Approaches to Study Different Aspects of the N Uptake Process.- 6.3 Studies with Excised Roots and Mycorrhizas.- 6.4 Field-Based Experiments.- 6.5 Conclusions.- References.- 7 The Fate of 15N-Labelled Nitrogen Inputs to Coniferous and Broadleaf Forests.- 7.1 Introduction.- 7.2 Sites of Investigation.- 7.3 Approaches to Study the Fate of 15N-Labelled Nitrogen Inputs.- 7.4 N Release and Tree Uptake from 15N-Labelled Decomposing Litter in a Beech Forest in Aubure.- 7.5 Ecosystem Partitioning of 15N-Labelled Ammonium and Nitrate on the Sites in the Fichtelgebirge and Steigerwald.- 7.6 Conclusion.- References.- 8 Canopy Uptake and Utilization of Atmospheric Pollutant Nitrogen.- 8.1 Introduction.- 8.2 Atmospheric Nitrogen Pollutants.- 8.3 Pathways for Canopy Uptake of Nitrogen.- 8.4 Approaches to the Determination of Canopy Uptake of Nitrogen.- 8.5 Review of Research.- 8.6 Role in the Critical Load.- 8.7 Ecophysiological Consequences of Canopy N Uptake.- 8.8 Conclusions.- 8.9 Way Forward.- 8.10 Policy Implications.- References.- 9 Biotic and Abiotic Controls Over Ecosystem Cycling of Stable Natural Nitrogen, Carbon and Sulphur Isotopes.- 9.1 Introduction.- 9.2 Approaches to the Study of Stable Isotopes in the Field.- 9.3 ?15N of Ammonium and Nitrate in Wet Deposition.- 9.4 Stable Isotope Signatures in Different Ecosystem Compartments.- 9.5 ?15N Signatures as Indicators of N Saturation in Forest Ecosystems.- 9.6 Conclusion.- References.- C Heterotrophic Processes.- 10 Soil Respiration in Beech and Spruce Forests in Europe: Trends, Controlling Factors, Annual Budgets and Implications for the Ecosystem Carbon Balance.- 10.1 Introduction.- 10.2 Approaches to Measuring Soil Respiration.- 10.3 Daily and Seasonal Trends in Soil Respiration and Climatic Variables.- 10.4 Factors Controlling Soil Respiration.- 10.5 Comparison of Chamber Measurements with the Eddy Covariance Measurements Below the Canopy.- 10.6 Annual Budgets of Soil Respiration.- 10.7 Conclusion.- References.- 11 Annual Carbon and Nitrogen Fluxes in Soils Along the European Forest Transect, Determined Using the 14C-Bomb.- 11.1 Introduction.- 11.2 Forests, Sampling Procedure and Analysis.- 11.3 Model Description.- 11.4 Estimations of C and N Pools and Fluxes.- 11.5 Pools and Distribution of Carbon and Nitrogen in Soil Profiles.- 11.6 Variations in the Carbon Age and Mean Residence Times (MRTs).- 11.7 Annual Carbon and Nitrogen Fluxes.- 11.8 General Discussion.- 11.9 Conclusion.- References.- 12 Carbon Mineralisation in European Forest Soils.- 12.1 Introduction.- 12.2 Experimental Backg