Publications
NIBIOs employees contribute to several hundred scientific articles and research reports every year. You can browse or search in our collection which contains references and links to these publications as well as other research and dissemination activities. The collection is continously updated with new and historical material.
1995
Authors
Richard Frederic Wright Tor Erik Brandrud Anna Clemmensson-Lindell Hans Hultberg O. Janne Kjønaas Filip Moldan Hans Persson Arne StuanesAbstract
No abstract has been registered
Authors
Richard Frederic Wright J.G.M. Roelofs M. Bredemeier Kai Blanck Andries W. Boxman Bridget A. Emmett Per Gundersen H. Hultberg O. Janne Kjønaas Filip Moldan Albert Tietema N. van Breemen H.F.G. van DijkAbstract
In large regions of Europe and eastern North America atmospheric deposition of inorganic nitrogen compounds has greatly increased the natural external supply to forest ecosystems. This leads to nitrogen saturation, in which availability of inorganic nitrogen is in excess of biological demand and the ecosystem is unable to retain all incoming nitrogen. The large-scale experiments of the NITREX project (nitrogen saturation experiments) are designed to provide information regarding the patterns and rates of responses of coniferous forest ecosystems to increases in N deposition and the reversibility and recovery of impacted ecosystems following reductions in N deposition. The nitrogen input-output data from the NITREX sites are consistent with the general pattern of nitrogen fluxes from forest ecosystems in Europe. At annual inputs of less than about 10 kg ha-1 year-1, nearly all the nitrogen is retained and outputs are very small. At inputs above about 25 kg ha-1 year-1 outputs are substantial. In the range 10-25 kg ha-1 year-1 these forest ecosystems undergo a transition to nitrogen saturation. The 10 kg ha-1 year-1 apparently represents the minimum threshold for nitrogen saturation.The NITREX experiments indicate that nitrogen outputs respond markedly across the 10-25 kg ha-1 year-1 range of inputs. In contrast, the nutrient concentrations in foliage, a measure of tree response, is delayed by several years. Nitrogen saturation can apparently be induced or reversed within only a few years, at least with respect to the commonly used diagnostic of nitrogen saturation-nitrogen output in leachate or runoff.
Authors
Richard F. Wright J.G.M. Roelofs M. Bredemeier K.. Blanck A.W. Boxman Bridget, A. Emmett Per Gundersen Hans Hultberg O. Janne Kjønaas Filip Moldan Albert Tietema Nico Van Breemen H.F.G. van DijkAbstract
No abstract has been registered
Authors
Albert Tietema Richard F. Wright K.. Blanck A.W. Boxman M. Bredemeier Bridget A. Emmett Per Gundersen Hans Hultberg O. Janne Kjønaas Filip Moldan J.G.M. Roelofs Patrick Schleppi Arne O. Stuanes Nico Van BreemenAbstract
No abstract has been registered
Authors
Albert Tietema Richard Frederic Wright Kai Blanck M. Bredemeier Bridget A. Emmett Per Gundersen H. Hultberg O. Janne Kjønaas Filip Moldan J.G.M. Roelofs Patrick Schleppi Arne Olav Stuanes N. van BreemenAbstract
In large regions of Europe and eastern North America atmospheric deposition of inorganic nitrogen (N) compounds has greatly increased the natural external supply to forest ecosystems. This leads to N saturation, in which availability of inorganic N is in excess of biological demand and the ecosystem is unable to retain all incoming N. The large-scale experiments of the NITREX project (NITRogen saturation EXperiments) are designed to provide information regarding the patterns and rates of responses of coniferous forest ecosystems to increases in N deposition and the reversibility and recovery of impacted ecosystems following reductions in N deposition.The timing of ecosystem response generally followed a hypothesized cascade of response. In all sites N outputs have responded markedly but to very different degrees within the first three years of treatment. Within this time significant effects on soil processes and on vegetation have only been detected at two sites. This delayed response is explained by the large capacity of the soil system to buffer the increased N supply by microbial immobilization and adsorption. We believe that this concept provides a framework for the evaluation and prediction of the ecosystem response to environmental change.
Authors
Erik Christiansen Alan A. BerrymanAbstract
No abstract has been registered
Authors
Tore SkrøppaAbstract
No abstract has been registered
Authors
Hans Fredrik Hoen Birger SolbergAbstract
No abstract has been registered
Authors
Finn Roll-Hansen Helga Roll-HansenAbstract
No abstract has been registered
Authors
Heli Viiri Kim von WeissenbergAbstract
No abstract has been registered