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.
2003
Authors
Per Otto Flæte Erlend Ystrøm HaartveitAbstract
No abstract has been registered
Authors
Jannes StolteAbstract
No abstract has been registered
Abstract
Mortality, injury and height growth of planted Picea abies (L.) Karst. were examined in a six-year period in eight stands in southeast Norway. There were four residual stand densities (shelterwoods of high, medium and low density, 25 x 25 m patch cut) combined with three scarification treatments (unscarified, patch scarification, inverting) in a split-plot design. Mortality was generally low during the experimental period, and did not differ significantly between the residual density treatments (mean=11.1%). Both survival and plant height after 6 years were improved by inverting, while patch scarification was intermediate but not significantly different from the unscarified alternative. The patch-cutting resulted in the tallest plants, while only minor differences in height growth were found between the shelterwood treatments. The frequency of injured plants after six years was not significantly affected by the treatments (mean=10.6%). The improved plant establishment with inverting in this study is in agreement with previous studies on clear-cuts.
Abstract
In this study of 130 sites with different management we investigated whether vascular plant species richness is significantly reduced when traditionally managed hay meadows are abandoned and reforested. We also compared the effects of reforestation with those of intensified land-use to see which have the largest effects on species richness. Finally, we investigated the relative importance of relevant ecological factors for species richness.While the use of artificial fertilizers in traditionally managed hay meadows has resulted in significantly lower species richness, and intensive cultivation in even lower species richness, abandonment with reforestation has not decreased the species richness significantly.Productivity and habitat diversity have determined the species richness of meadows on the scale (0.035.1 ha) of this study. Low productivity is a prerequisite for high species richness in meadows. Maximum species richness was observed in unproductive, old, traditionally managed hay meadows with a high soil pH and high habitat diversity. The high species richness of these meadows suggests that they are in urgent need of conservation.
Authors
Lars HögbomAbstract
No abstract has been registered
Authors
Atle Hindar Richard Frederic Wright Petter Nilsen Thorbjørn Larssen R. HøgbergetAbstract
An acidified, 0.8km2 coniferous-forested catchment was limed with 3tha-1 of coarse-grained dolomite powder in September 1994. The liming resulted in an immediate change in runoff water chemistry relative to the stream of an adjacent reference catchment. pH, calcium, magnesium and acid neutralising capacity (ANC) increased and inorganic Al decreased after liming.Potential favourable water quality for sensitive organisms remained relatively constant over the post-liming period (7 years), and model simulations indicate that adequate water quality may last for an additional 4050 years. NO3 concentrations showed no significant change due to liming.A significant increasing trend in TOC was attributed to liming. Concentrations of Cd, Co, Fe, Mn, Ni and Zn were lower in the limed stream than in the reference stream during a period of 3 years after liming, whereas concentrations of As, Cu, and Pb were not significantly different. Steep slopes, thin soils, high amounts of precipitation and thus dominance of surface and subsurface flow in this catchment may explain the rapid response in runoff.During the first 6 years after liming there have been no significant effects on tree growth and vitality (crown density and crown colour). This experiment shows that liming of forested catchments may be a viable method to obtain long-term improvement in water quality and potential positive effects for acid-sensitive aquatic organisms.
Abstract
No abstract has been registered
Abstract
No abstract has been registered
Authors
Tore SkrøppaAbstract
No abstract has been registered
Abstract
No abstract has been registered