The overall objective of NITREX II is to obtain direct experimental data at the ecosystem scale regarding (1) the risk of nitrogen saturation due to nitrogen deposition and (2) the recovery of nitrogen saturated systems in response to decreased nitrogen deposition.
NITREX is an international, interdisciplinary research project focused on the impact of nitrogen on forest ecosystems. The project addresses the role of nitrate and ammonium in acidification of soil and water by addition or removal of nitrogen to precipitation falling on headwater catchments and forest stands. These experiments comprise a six-nation European network spanning the gradient in nitrogen deposition form <5 kg ha-1 yr-1 in Norway to >50 kg N ha-1 yr-1 in the Netherlands.
Among questions central to NITREX are :
(1) What is the threshold for nitrogen saturation in coniferous forest ecosystems ?
(2) Is nitrogen saturation reversible, and if so, when and how does recovery proceed ?
(3) What is the critical load for nitrogen in coniferous forests of Europe ?
(4) What is the role of nitrogen in ecosystem acidification and forest decline ?
A detailed description of the project is made in Ecosystems Research Report no 2 of the Commission of the European Communities.
This report is available from P. Mathy (Fax : 32-2-296.30.24).
Funding SchemeCSC - Cost-sharing contracts
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LL57 2UW Bangor
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