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.
2001
Authors
Mehreteab TesfaiAbstract
No abstract has been registered
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Authors
Gunnar Ogner Guro Randem Torild WickstrømAbstract
Analyses of forest soils are widely used to monitor the effects of human activity on our environment. The overall quality of analytical data must, therefore, be sufficient to answer questions with regard to environmental changes taking place throughout several decades.Three horizons of an air-dried forest soil, was stored at 22 3 C, 3 C and 21 C for up to 1842 d to monitor its stability during storage. At room temperature, soil acidity increased and soil pH in water decreased by 0.1 to 0.3 pH units depending upon the soil horizon.The amount of C, P, and S extracted by 1M ammonium nitrate increased by 94%, 62% and 68%, respectively, after 1842 d. A corresponding increase in exchangeable cations [aluminium(Al), barium(Ba), calcium (Ca), magnesium (Mg), manganese (Mn), strontium (Sr), and zinc (Zn)] ranged from 11 to 23%. Storage at 3 C resulted in a decrease in pH only for mineral soil (10-15 cm layer). At 21 C, no changes in any of the soil-extractable components were found.
Authors
Jan Mulder Heleen A. de Wit Helena W.J. Boonen Lars R. BakkenAbstract
No abstract has been registered
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The cherry cultivars "Van", "Ulster" and "Burlat" grafted on the rootstocks seedling, `Colt" and `Gisela 5" were evaluated for important fruit quality parameters at Ullensvang Research Centre during the 1998 season. The largest fruit size was found on the cultivar/rootstock combinations `Van"/seedling, `Ulster/Colt" and `Burlat/Gisela 5". Other parameters like fruit firmness, stone weight, soluble solids, titratable acids and pH of the fruit juice were registered as well.
Authors
Dagang Tang Espen Lydersen H.M. Seip Valter Angell Odd Eilertsen Thorbjørn Larssen X Liu G. Kong Jan Mulder Arne Semb Svein Solberg K. Torseth Rolf D. Vogt Jinshong Xiao Dawei ZhaoAbstract
A 5-year Chinese-Norwegian research project was launched in the autumn of 1999. Forested sites for intensive studies are or will be established in the Chongqing municipality and in Guizhou, Hunan and Guangdong provinces in southern China. Previous studies have shown that harmful effects of acid deposition are likely to be most severe in this region. The research and monitoring sites shall give information about acidification mechanisms and effects on vegetation in order to improve policy oriented acidification models and critical load estimates as well as function as interdisciplinary training centers for acid rain research. Furthermore, the project shall improve the basis for developing an efficient regional acid rain monitoring system. At one site in Guizhou and one in Chongqing, research on soil and soilwater chemistry has been ongoing for several years. The forest at these sites appears to show symptoms of reduced vitality. The sensitivity of Chinese forests to acidification is uncertain and will be focused. Decision-makers should get an improved basis for optimal mitigation measures through the project.
Authors
Wenche E. Dramstad Gary L.A. Fry Wendy Fjellstad Birgitte Skar Wenche Helliksen May Liss Bøe Sollund Mari Sofie Tveit Anne Katrine Geelmuyden Erik FramstadAbstract
An accumulating body of research identifies the importance of landscape structure for a wide range of countryside interests. Landscape structure reflects the results of policies and practices, and is well-suited as a target for management actions. New landscape metrics represent a potential for indicator-based management, provided such metrics relate consistently to the landscape values of interest. In this paper we propose that aspects of landscape structure, specifically heterogeneity, may be related to landscape-based values such as biodiversity, cultural heritage and human appreciation. Birds and vascular plants correlated well with our index for the heterogeneity of land types, whereas insects did not. Occurrence of prehistoric graves was also associated with land type heterogeneity, though other types of cultural remains were not. Landscape experience seems to be associated with the heterogeneity of landscape space rather than heterogeneity of land types. Different aspects of heterogeneity, scale, and variation over time all contribute to explain how our measures of landscape-based values vary in their relationship to landscape heterogeneity. Successful integration between disciplines in landscape studies depends on having a common operational framework, a shared theoretical basis, and a harmonised approach to data collection.
Authors
Lars Olav Eik Leif Jarle AsheimAbstract
Sheep and goat farming systems in this part of Europe are based on extensive use of non-fertilised natural pastures and a long barn-feeding period. One million ewes are kept for the production of meat and wool while 60,000 goats are kept mainly for themilk. The local demand for organic meat and milk is increasing gradually and 10 percent of the agricultural area is projected to be managed according to organic principles by 2010. This paper discusses the feasibility of introducing cashmere goats in an organic sheep farming production system, based on economical calculations in a Linear Programming model. Significant movements from sheep to cashmere goats production are entirely as slaughtering of eight months old kids (11 kg) is unprofitable, assuming equal labour input of goats and sheep. Yields of meat and cashmere could be improved by feeding the kids until 20 months (19 kg) so possibly making goats as profitable as sheep. The benefits of high value cashmere production and controlling bush encroachment by goats favour a mixed farming system. If yield-levels of roughage can be maintained at 75% without artificial fertilizers and challenges in housing of small ruminants are solved, a shift away from conventional farming is profitable given the current support for organic farming.
Authors
Lars Olav Eik Leif Jarle Asheim Tormod ÅdnøyAbstract
No abstract has been registered