Publikasjoner
NIBIOs ansatte publiserer flere hundre vitenskapelige artikler og forskningsrapporter hvert år. Her finner du referanser og lenker til publikasjoner og andre forsknings- og formidlingsaktiviteter. Samlingen oppdateres løpende med både nytt og historisk materiale. For mer informasjon om NIBIOs publikasjoner, besøk NIBIOs bibliotek.
2012
Sammendrag
The current IPCC guidelines define an estimate for the fraction of mineral fertilizer and animal waste (manure) lost to leaching and runoff (FracLEACH). The FracLEACH default is 30 %. In Norway, 18 % has been used based on calculations made in 1998 (Vagstad et al., 1998). The main purpose of this study was to give an updated estimate of nitrogen (N) leaching in relation to the amounts of N applied in agriculture (FracLEACH). The term losses in this report include both surface and subsurface runoff. The estimates of FracLEACH presented in this report were based on data from the Agricultural Environmental monitoring program (JOVA). The JOVA-program includes catchment and field study sites representing typical situations in Norwegian agriculture with regard to production system, management, intensity, soil, landscape, region and climate. Data from plot- scale study sites confirmed the level of N leaching from the agricultural areas within the JOVA catchments. The overall FracLEACH estimated in this study was 22 % of the N applied. This average covers a variation between sites from 16 % on grassland in Valdres to 44 % in intensive vegetable, potato and cereal production areas in the southernmost part of Norway. Runoff is the most significant parameter for the difference in FracLEACH between catchments. In addition, production system and to some degree soil type are important for FracLEACH. It is thus suggested to use different FracLEACH-values for the different production systems and adjust FracLEACH according to average runoff for the region.
Sammendrag
The purpose of the study was to explore and compare three different methods for modelling potential natural vegetation (PNV), a hypothetic natural state of vegetation that shows nature's biotic potential in the absence of human influence and disturbance. The vegetation was mapped in a south-central Norwegian mountain region, in a 34.2 km2 area around the village of Beitostølen, in 2009. The actual vegetation map (AVM) formed the basis for the development of PNV using three different modelling methods: (1) an expert-based manual modelling (EMM), (2) rule-based envelope GIS-modelling (RBM), and (3) a statistical predictive GIS-modelling method (Maxent). The article shows that the three modelling methods have different advantages, challenges and preconditions. The findings indicate that: (1) the EMM method should preferably be used only as a supplementary method in highly disturbed areas, (2) both the RBM and the Maxent methods perform well, (3) RBM performs especially well, but also Maxent are more objective methods than EMM and they are much easier to develop and re-run after model validation, (4) Maxent probably underestimates the potential distribution of some vegetation types, whereas RBM overestimates, (5) the Maxent output is relative probabilities of distribution, giving higher model variation than RBM.
Sammendrag
This report has been prepared in the frame of Work Package 3 (Policy) of the Interreg IVB project Bioenergy Promotion. The main rationale of this work package is to support the development of coherent national and (sub)regional policies promoting the sustainable production and consumption of bioenergy. The purpose of the country policy assessment report is to describe the main promotional policies and support schemes for bioenergy and to assess to what extent national policy frameworks contribute to Sustainable Development and integrate related sustainability principles and criteria. At present and in the foreseeable future, the main source of raw materials for bioenergy in Norway is likely to be the forests. However, waste from agriculture, households and industry is another promising source. Investment support needs to be continued, at least at present levels. The main bottlenecks for increased use of bioenergy in Norway are economic, so economic support is necessary. Further development of the standard for sustainable forestry is required, in order to take into account aspects that are not yet covered (see above under Point 3.5). However, there is currently disagreement between the parties to the Living Forests standard, so revision is not likely to take place soon. Current research is being carried out, for example in CenBio and the project “Ecological consequences of increased biomass removal from forests in Norway” on the effects of whole-tree harvesting compared to stem-only harvesting on soil nutrients, carbon stocks, ground vegetation and regeneration). In addition, work is being carried out to study the applicability under Norwegian conditions of the guidelines of other countries such as Sweden, Finland, the UK and Ireland and to prepare preliminary guidelines for Norwegian forestry. There is disagreement on the likely short-term effects of biomass harvesting for bioenergy on carbon sequestration in forest ecosystems (see above under 5.2) and this needs to be further studied. In their present form, the binding EU sustainability criteria for biofuels/bioliquids should not be extended to solid/gaseous biomass used for electricity and heating/cooling. Some changes are necessary to take account of specific conditions e.g. in forestry. For example, it is stated in Point 4 of Article 17 of the Renewable Energy Directive that biofuels and bioliquids shall not be obtained from land that was continuously forested in January 2008 and is no longer continuously forested. It is unclear how this would affect clear-cuts. Also, in Point C7 of Annex V, the 20-year period for calculating carbon stock changes is completely unrealistic for forestry (although this refers to land-use change and it could be argued that felling is not land-use change if the land is used for forest afterwards; this should be clarified). These aspects of the Renewable Energy Directive are already problematic if forest biomass is to be used for biofuels or bioliquids.
Sammendrag
A crucial process of the terrestrial carbon cycle is photosynthetic uptake through plants. This may be quantified by calculating the fraction of absorbed photosynthetic active radiation (fapar), based on multispectral reflectance properties of the earth surface. The fapar index is available with global coverage from satellite sensors.Here, we combine two satellite missions, SeaWifs on board OrbView2 and MERIS on board Envisat, to produce time series with 10 days resolution for a period of 14 years (19982011) at a spatial resolution of 0.5 latitude x 0.5 longitude. These more than 50000 individual time series represent a huge range of dynamical behavior with respect to variability, periodicities and correlation structure.To characterize differences as a function of spatial location or distance, we employ Recurrence Quantification Analysis (RQA) and Recurrence Network Analysis (RNA). Two strategies are followed. On one hand, RQA and network variables are calculated for individual time series using identical recurrence parameters, and compared to see whether differences between them resemble different climate regimes, biomes, plant functional types or landuse classes. On the other hand, a multivariate extension of RNA will be exploited to see whether networks within networks occur, i.e. whether RNA provides sufficient contrasts to discern different clusters of pixels on the globe.Taken together, the recurrence analysis might lead to a new classification of the terrestrial biosphere which in turn can be compared to existing partitioning based on climate and/or vegetation properties. A number of technical issues will be addressed as well, such as the impact of the finite length of the series (504 values each), the necessity to gapfill parts of the data, the stability of network variables against changes in the recurrence parameters, or the computational challenges involved in the multinetwork analysis of many series. http://dames.pik-potsdam.de/Abstracts.pdf
Forfattere
Jogeir N. StoklandSammendrag
Det er ikke registrert sammendrag
Sammendrag
In 2008, an epidemic caused by a new Neonectria sp. was discovered on white fir (Abies concolor) in several counties in southern Norway [1]. Later the pathogen was also found on other fir species in Norway and Denmark [2]. Typical symptoms and signs were dead shoots, flagging (dead branches), canker wounds, heavy resin flow, and occasionally red fruiting bodies (perithecia). Pathogenicity tests on several Abies spp. proved the fungus to be very aggressive, which corresponds well with observations of mortality of white fir and subalpine fir (A. lasiocarpa) from different age classes under field conditions. Sequencing of the internal transcribed regions (ITS) of the ribosomal DNA showed that this Neonectria sp. was most similar to N. ditissima (only 5 bp different from isolates in the GenBank), a common pathogen worldwide on broad leaf trees. The ITS sequences were very different (> 20 bp) from N. fuckeliana, a well-known fungus on Norway spruce in Scandinavia and other parts of the world, especially in the northern hemisphere. In 2011, the new Neonectria species was found on diseased trees in a Danish nordmann fir (Abies nordmanniana) seed orchard. Resin flow was seen from mature cones, and tests revealed that the seeds were infected by the Neonectria sp.
Forfattere
Jonathan Edward Colman Diress Tsegaye Alemu Christian Pedersen Ruben Eidesen Herbjørg Arntsen Øystein Holand Alex Mann Eigil Reimers Stein Ragnar MoeSammendrag
Interspecific interaction among sympatric ungulates is important in management and conservation. We investigated behavioral interference between sympatric wild or semidomestic reindeer (Rangifer tarandus tarandus) and sheep (Ovis aries) in two field studies and one enclosure experiment. For free-ranging wild and semidomestic reindeer, interference between the two species increased with decreasing distances, occurring only at less than 200 m and 30 m, for wild and semidomestic reindeer, respectively, and neither species consistently dominated the other. In a controlled, duplicated experiment we tested interference and confrontations at the feeding patch level among semidomestic reindeer and sheep within 40 × 50 m enclosures. When new reindeer or sheep were introduced into enclosures already occupied by reindeer, new reindeer resulted in significantly more interference and confrontations among individuals compared to new sheep; i.e., intraspecific interference was more prevalent than interspecific interference at equal densities. For all study areas, confrontations decreased with time after “first encounter,” indicating cohabituation. A sympatric use of pastures was not visually disruptive for recorded grazing behavior for either species.
Sammendrag
Adapting to changing climate is essential for individuals and communities to sustain their livelihoods. Improving adaptive capacity at various levels is essential, and this can be done by strengthening ongoing initiatives, introducing new measures, training and capacity building. One of the main focus areas of the Climarice projects is to train the farmers on implementing various adaptation technologies that would increase the water and nutrient use efficiencies at field level. Climarice project scientists have identified various technologies such as usage of biofertilizers such as blue green algae and azolla to improve the nutrient use efficiency in paddy cultivation, application of green manures to enhance soil organic matter content, introduction of short duration rice cultivar during delayed monsoon, cultivation of alternate crops for income generation, System of Rice intensification for enhancing water and grain productivity, usage of bio control agents such as Trichoderma and Pseudomonas for eco friendly management of pest and diseases etc.,. For the successful implementation of these technologies at field level, the farmers have to be given with training and exposure visits. ClimaRice project scientists have undertaken many capacity building programmes to farmers of Cauvery basin on various adaptation technologies and these programmes have created confidence among the farmers. Many farmers who have attended the training programmes are following the technologies with great interest. A summary of the training programmes and their impact are furnished in this report.
Sammendrag
Ceratocystis polonica and Heterobasidion parviporum are important fungal pathogens in Norway spruce (Picea abies). Tree susceptibility to these pathogens with respect to phenology was studied using artificial fungal inoculations at six stages of bud development, and assessed by measuring phloem necroses in the stems of 2- and 8-year-old trees. Tree capacity for resistance was assessed by measuring phloem nonstructural carbohydrates at each stage. Phloem necroses were significantly larger in trees with fungal versus control inoculations and increased significantly over time. Changes in nonstructural carbohydrates occurred in the trees; a significant decline in starch and a slight but significant increase in total sugars occurred over time. These results suggest that susceptibility to fungal pathogens and carbohydrate levels in the stems of the trees were related to fine-scale changes in bud development. A trade-off may occur between allocation of starch (the major fraction of the stem carbohydrate pool) to bud development/shoot growth versus defence of the stem. Previous tests of plant defence hypotheses have focused on herbivory on plants growing under different environmental conditions, but the role of phenology and the effect of pathogens are also important to consider in understanding plant resource allocation patterns.
Sammendrag
Pilgrims travel along the main reopened St Olav pilgrim routes in Norway and visit a variety of cultural heritage types. These routes are part of a value creation programme, in which the management authorities try to increase the numbers of pilgrims. At the same time, forest regrowth is reported to reduce the landscape experience of pilgrims and to biophysically change the cultural heritage sites. However, no studies have been reported on the spatial encroachments of forests along the pilgrim routes. The purpose of this study is to analyse where forest regrowth along the main reopened pilgrim routes in Norway will appear, given the present climatic conditions, and to assess the spatial overlap of future forest regrowth with cultural heritage sites. A potential forest model and a cultural heritage sites database were combined with several baseline geographical data layers and spatially joined in geographical information systems. The results show that most of the future forest regrowth will appear in mountainous parts of the pilgrim routes, whereas many hunting sites, tradition sites and other cultural heritage sites will be overgrown by young forests. Therefore, management efforts to keep the main pilgrim routes open need to be strengthened and directed towards future risks.