Using European data, as well as several regional databases, the purpose of this project is to identify and validate key parameters and empirical relationships (indicators and transfer functions) relevant to carbon (C) and nitrogen (N) that signify changes in forest ecosystem functioning or environmental impacts. CNTER is an interdisciplinary collaborative project and data from several hundred study and monitoring sites, and results from long-term nitrogen addition and labelling experiments, will be used to gain new insights into carbon and nitrogen interactions in forest soils, especially the effect of N deposition on the soil C sink. The re-sampling of long-term N addition experiments will form a validation of the identified empirical relationships. Data and process insights will be used to improve and validate dynamic models for prediction in time and space. The major ecosystem impacts being considered are changes in forest soil carbon storage and changes in nitrate concentrations in forest waters.
CNTER will combine data integration, experimentation and modelling to characterise the interaction of carbon (C) cycles, nitrogen (N) cycles and physical factors in forest ecosystems. The general objectives are:
1) to identify and validate indicators of the forest ecosystem state, and environmental risks and impacts related to C and N (i.e. CO▓ sequestration, acidification and nitrate pollution of forest waters)
2) to gain new insights in C and N interactions in forest soils, especially the effect of N deposition on the soil C sink
3) to provide estimates of C sequestration and N retention in the forest ecosystem under current and future conditions, given scenarios for major environmental change drivers: land use, air pollution and climate
4) to develop empirical and dynamic models that allow extrapolation of C and N risks and impacts in forests on regional and European scales
5) to provide guidelines for forest management to optimise environmental benefits (CO▓ sequestration and N retention).
Progress to Date
Preliminary versions of comprehensive databases on carbon (C) and nitrogen (N) fluxes and pools in European forests have been compiled for internal use. These databases have been explored to create empirical models that predict C accumulation and N retention/nitrate leaching from N input, climate and ecosystem characteristics.
First estimates of C and N sequestration in the organic layer of forest have been calculated based on 'the limit value concept' that uses data from studies on the decomposition of organic matter. Preliminary European images and regional estimates of present day C sequestration in forest soils have been calculated in several ways.
Long-term field experiments, including additions of stable N isotopes, have been re-sampled.
The project aims to produce guidance on forest management to optimise environmental benefits of forests (C sequestration and water protection). Reviews on the current knowledge of these issues have been produced and the first experimental results reported.
The analyses of compiled databases showed, regarding nitrate leaching, that there is a threshold N deposition of 10 kg N/ha/yr below which almost no leaching occurs.
Estimates of C and N sequestration in the organic layer of forest calculated, based on 'the limit value concept', were validated on sites where humus accumulations are known, and it seemed to work well. Using this method, it will be possible to calculate C sequestration in the organic layer over Europe when data has been gathered for a sufficient number of sites. Re-sampled long-term field experiments including additions of stable N isotopes will allow for thorough testing and validation of a process model that predicts the fate of N in the ecosystem. From this detailed knowledge on N, C accumulation and fluxes in the system can be estimated for experimental sites.
FORESTRY, SOIL, NON-FOOD PRODUCTS
Scientist responsible for the project
Mr PER GUNDERSEN
Hoersholm Kongevej 11
Denmark - DK
Phone: +45 45178201
Fax: +45 45763233
||Danish Forest and Landscape Research Institute
||01 August 2001
||2 670 878 €
|Total EC contribution
||1 397 321 €
|Web address of the project
- University of Amsterdam, Institute for Biodiversity and Ecosystem Dynamics, Netherlands (The) - NL
- Centre for Ecology and Hydrology (CEH-Bangor), United Kingdom (The) - GB
- Marine Biological Laboratory (MBL), United States (The) - US
- Danish Forest and Landscape Research Institute (Skov & Landskab), Denmark - DK