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.
2007
Forfattere
Hans OvergaardSammendrag
Global change certainly affects the epidemiology of vector borne diseases (VBD). A changing climate may cause shifts in the intensity and endemicity of VBD"s. Both direct effects (e.g. changes in temperature and rainfall) and indirect effects (e.g. changing local environmental conditions) of climate change influence disease vectors and the disease-causing organisms they carry. Substantial research efforts are required to predict the effects of future climate scenarios on changes in magnitude and spatial distribution of VBD"s. Similarly, more research is needed to explore innovative locally-adapted solutions to control vectors and VBD"s. Two promising tools are presented, that can be implemented under local conditions and be adapted to changing environmental and climatic conditions. Integrated Pest and Vector Management (IPVM) is a strategy to simultaneously control both agricultural pests and disease vectors. The strategy is a combination of Integrated Vector Management (IVM) and Integrated Pest Management (IPM). IVM seeks to improve vector control by implementing synergistic combinations of interventions based on knowledge of local vector biology and disease transmission. IPM is the corresponding strategy in agricultural pest control and aims to reduce pesticide use for the benefit of human and environmental health. Both IVM and IPM preserve beneficial organisms and lessens selection pressure for insecticide resistance. These strategies can be implemented through Farmer Field Schools (FFS) " a participatory non-formal education approach teaching farmers how to reduce pesticide use through field observation and experimentation. These approaches ensure community empowerment for the benefit of health promotion, rural development, and preparedness for adverse global change effects.
Forfattere
Hans OvergaardSammendrag
Global change will likely affect the epidemiology of vector borne diseases (VBD). A changing climate may cause shifts in the prevalence and intensity of VBD"s. Both direct effects (changes in temperature and rainfall) and indirect effects (changing local environmental conditions) of climate change influence disease vectors and the disease-causing organisms they carry. Substantial research efforts are required to predict the effects of future climate scenarios on changes in magnitude and spatial distribution of VBD"s. Research is also needed to explore innovative locally-adapted solutions to control vectors and VBD"s. Solutions that can be easily adapted to local situations and changing environmental and climatic conditions are more likely to be effective and sustainable. The Integrated Pest and Vector Management (IPVM) approach is a promising solution. IPVM is a recently developed concept based on community participation and agroecosystem management aiming to control both agricultural pests and disease vectors in an environmentally friendly and sustainable manner. IPVM originates from the Integrated Pest Management (IPM) approach, which is commonly implemented through Farmer Field Schools (FFS). IPM is a crop protection strategy with focus on biological control aiming to reduce pesticide use for the benefit of human and environmental health. FFS is a participatory non-formal education approach teaching farmers the principles of biological control through agroecosystem analysis, field observations, and experimentation. IPM implemented through FFS has led to reduced crop losses, less pesticide input, increased profitability, and improved environmental management and farmer empowerment. By adding modules on vector ecology, vector control, disease cycle, etc. to the FFS curriculum local communities may contribute to improved vector control by implementing synergistic combinations of interventions based on knowledge of local vector biology and disease transmission (i.e. Integrated Vector Management, IVM). These approaches preserve beneficial organisms, lessen selection pressure for insecticide resistance, and ensure community empowerment for the benefit of health promotion, rural development, and preparedness for adverse global change effects.
Forfattere
Hugh RileySammendrag
Factorial combinations of N, P and K fertilizer have been compared with the use of farmyard manure at Møystad since 1922 in a seven-year crop rotation (3 ley, oat, potato, wheat, barley). Until 1982, low inputs of N fertilizer (22 kg ha-1) were used. In 1983, they were brought into line with current farming practice. This paper presents results of three subsequent rotations. Yields without any fertilizer were on average 48% of those with 100 kg N ha-1 in compound fertilizer, whilst those with 20, 40 and 60 Mg ha-1 farmyard manure were 81, 87 and 90%, respectively. Yields with other combinations of N, P and K declined in the order NP, NK, N, PK and K. When NPK fertilizer was used, apparent recoveries of applied fertilizer were close to 50% for N and K, and around 40% for P. Much lower values were found for nutrients applied singly. Balance between N supply and removal was indicated at rates of about 60 kg N fertilizer ha-1 in potatoes, 75 kg ha-1 in cereals and 90 kg ha-1 in leys. A surplus of P was found in all crops at all N levels, and of K in cereals and potatoes. In leys, K balance was achieved with an N supply of 90 kg N ha-1. Nutrient balance was indicated at a little below 20 Mg ha-1 yr-1 farmyard manure. Larger manure applications gave large nutrient surpluses, particularly of N. Soil reaction remained close to neutral with the use of calcium nitrate and manure, but declined with the use of ammonium nitrate. Manure use gave the highest amounts of available P, K and Mg in soil. Similar increases in total inorganic P were found with manure use as with fertilizer use, but amounts of organic P and total K were little affected.
Forfattere
Celine ReboursSammendrag
Laminaria has been known in Asia, first as kunbu ("large cloth") and, more recently, as haidai ("sea ribbon"). Internationally, "kelp" is generally used. The main extracted products are alginate, iodine and mannitol, which are used in textile, printing, medical and food manufacturing industries. Laminaria in its whole is also used in a huge variety of products for human consumption. In Europe, the exploited species have been L. digitata, hyperborea and saccharina. Mostly harvested as source of saltworth and iodine, wild thallus have also been used as fertizers in agriculture. In 2005, Laminaria is still harvested as alginates sources in Norway (L. hyperborea : 153 906 t) and France (L. digitata : 74 778 t). No cultivation is actually in place. In the late 1920s, the commercial seaweed Laminaria japonica was introduced into China from Hokkaido (Japan). Although commercial production of kelp harvested from its natural habitat has been carried out in Japan for over a century, mariculture of this cold water species on a very large commercial scale has been realized in China in the 1950s. Since, the Chinese kelp production increased from about 60 000 t annually to over 4 millions tones in 2005, making China the world largest producer of Laminaria. The Chinese success of the kelp cultivation in Asia has mainly depended on the adoption of three important techniques: the floating raft method, low temperature cultivation of summer seedlings, and application of nitrogen fertilizer in the open sea. The Chinese methods that have made Laminaria production successful are shortly described in this poster.
Forfattere
Marie-France Dignac Cornelia Rumpel Daniel Rasse Mercedes Mendez-Millan Haithem Bahri André MariottiSammendrag
Little is known on the relationship between the chemical composition and the dynamics of plant biomolecules in soils at the long-term scale. Chemical recalcitrance of specific molecules such as lignins has been proposed as a possible factor governing organic matter stabilization in soils. Other stabilization mechanisms, involving soil mineral constituents, may act differently on above- and belowground tissues of plants, leading to contrasting contributions of these tissues to soil organic matter (SOM). Cutins and suberins are present respectively in the aboveground and the belowground tissues of higher plants and can be used as biomarkers of the inputs of these plant tissues to soils. Using compound specific isotopic tracer techniques applied to agricultural lands converted from C3 plant to C4 plant cropping, we followed the molecular turnover of lignins, cutins and suberins in soils, in order to assess their specific residence times, and infer the contributions of above- and belowground tissues to SOM. We showed that lignin turnover in soil is faster than that of total organic carbon. We evidenced contrasting behaviour of lignin as well as cutin/suberin monomers on a molecular basis which may be related to their chemical nature, their position into the polymeric structure and to the plant tissue in which they are present. Therefore, we suggest that compound specific isotope measurements in combination with longterm field trials could lead is understanding of soil carbon stocks and fluxes on a molecular level.
Forfattere
Trygve S. Aamlid Gunvald Henning JonassenSammendrag
Field trials comparing various combinations of 0, 30 or 60 kg N ha-1 in autumn (September) and/or spring (April) to seed crops of common bent (syn. browntop, US: colonial bentgrass, Agrostis capillaris L.) "Leikvin" (main use: long-lasting pastures and utility turf) and "Nor" (main use: lawns and golf course fairways) were carried out on silt loam soils at Landvik, south-east Norway (58°N) from 1989 to 1994. One trial per cultivar was established in 1989, 1990 and 1991, each trial being harvested for three years. On average, for nine harvests and nine N treatments, "Leikvin" and "Nor" gave seed yields of 276 and 128 kg ha-1, respectively. Seed yields of "Leikvin" increased with increasing N rate up to 60 kg N ha-1 in autumn and 30 kg N ha-1 in spring; no interaction between autumn and spring N rate could be detected in this cultivar. In "Nor", a significant autumn x spring rate interaction indicated a linear seed yield response to N in spring on plots that had received 60 kg N ha-1 in autumn, but a diminishing response to N in spring on plots that had received 0 or 30 kg N ha-1 in autumn; the highest seed yield was produced with autumn + spring applications of 60 + 60 kg N ha-1 in this lawn cultivar. While panicle number and seed number per panicle were equally important for seed yield in "Leikvin", panicle number had the stronger impact on seed yield in"Nor". Seed crops of "Leikvin" were generally taller and more susceptible to lodging than seed crops of "Nor". Year-to-year variations in seed yield level and optimal N regime were less related to crop age than to weather conditions and seed crop management. Given the present prices for fertilizer and seed, it is concluded that Norwegian seed crops of common bent should receive 50-60 kg N ha-1 in autumn regardless of cultivar. Economically optimal N rates in spring are 30 and 60 kg N ha-1 to "Leikvin" and "Nor", respectively.
Forfattere
Trygve S. Aamlid Gunvald Henning JonassenSammendrag
As part of a project to stimulate Norwegian seed production of common bent (syn. browntop, US: colonial bentgrass, Agrostis capillaris L. syn. A.tenuis Sibth.) field trials comparing sowing rates 2.5, 5.0, 7.5 or 10 kg ha-1 were conducted at Landvik, SE Norway, (58ºN) from 1989 through 1994. Three trials were laid out in the forage cultivar `Leikvin" and three trials in the lawn cultivar `Nor", each trial being harvested for three consecutive years. While the average per cent ground cover in spring increased from 87% at 2.5 kg ha-1 to 94-96% at 7.5 kg ha-1, seed yields decreased with increasing sowing rate in both cultivars. On average for all harvests, quadrupling the sowing rate from 2.5 to 10 kg ha-1 reduced seed yield by 9% in `Leikvin" and 15 % in `Nor", the stronger effect probably being associated with a greater competition between tillers in the lawn cultivar. Seed yield reductions with increasing sowing rate showed no relationship with crop age, but were less accentuated for crops undersown in spring wheat in a dry year than for crops established without cover crop in years with ample rainfall in early summer. Increasing sowing rates reduced plant height and panicle number in `Nor", but had no effect on seed weight or germination in any of the cultivars. It is concluded that seed crops of common bent ought to be established with a sowing rate of 2-5 kg ha-1, with the lowest rate in lawn cultivars, under ideal seedbed conditions and when seed crops are sown without cover crop.
Sammendrag
Quantifying P losses to surface waters at different scales and partitioning of the loads into P losses from point sources and diffuse sources are significant future challenges for river basin managers. The agricultural share of P losses to surface waters is, in many river basins, increasing and therefore becoming more important to quantify and analyse. The importance of phosphorus losses from agricultural land was analysed using monitoring data and two different models for 35 micro-catchments (50 000 km2). Average annual phosphorus loss from agricultural land in the micro-catchments varied from 0.1 to 4.7 kg P ha)1 and showed no relationship with the short-term P surplus on agricultural land. The average annual total P loss from agricultural land showed equally large variation in the 17 macro-catchments (0.1"6.0 kg P ha)1), but the range was less for the 10 larger river basins (0.09"2.0 kg P ha)1). The annual P loss from the 35 micro-catchments was greatest in the micro-catchments characterized by soil erosion and a high proportion of surface run-off as in the Norwegian catchments. The same pattern was true for the 17 macro-catchments where the model-simulated total P loss from agricultural land was greatest in the catchments in northern and southern parts of Europe. The main diffuse pathways for total P loads in the 17 macro-catchments were simulated with the MONERIS model. On average, soil erosion and surface run-off was estimated to have contributed 53% (4.1"81%), groundwater 14% (0.2"41.7%) and tile drainage water 3% (0"14.0%).
Forfattere
Kinga Adam Tore Krogstad Lasse Vråle Anne Kristine Søvik Petter D. JenssenSammendrag
Filtralite P® and shellsand as ideal constructed wetland substrates have been tested for their P sorption capacity, both with batch and column experiments. Two columns were filled with Filtralite P® and one column with shellsand. The shellsand (SSPS) and one of the Filtralite P® columns (FLSP) were loaded with a synthetic P solution, while the second Filtralite P® column (FLWW) was loaded with secondary wastewater. Ca, Mg, pH and the P concentrations were measured in the inlet and the 7 outlets along the height of the three vertical upflow columns for up to 303 days. An overall P removal rate of 92, 91 and 54% was measured in the columns SSPS, FLWW and FLPS, respectively, for the entire experimental period. The comparison of FLWW and FLPS showed that FLWW kept its high P removal efficiency (91%) throughout the experimental period while the removal efficiency of FLPS decreased fast after reaching the 1 ppm effluent P concentration. The competition of other negative ions and the development of biofilm did not have a negative effect on P removal from wastewater. The batch experiments showed a better sorption capacity of Filtralite P® at low initial concentrations, while for high initial concentrations the shellsand sorbed more. Shellsand had, however, a higher sorption capacity in batch experiments with used column material and high initial P concentrations. The results from both the batch and the column experiment suggest that the shellsand has a more durable P sorption capacity than the Filtralite P® material, possibly due to the persistent high concentrations of Ca in the shellsand.
Forfattere
H.-S. Helmisaari M. Salemaa J. Derome O. Kiikkilä Christian Uhlig T.M. NieminenSammendrag
The main aim of this study was to determine how the application of a mulch cover (a mixture of household biocompost and woodchips) onto heavy metal"polluted forest soil affects (i) long-term survival and growth of planted dwarf shrubs and tree seedlings and (ii) natural revegetation. Native woody plants (Pinus sylvestris, Betula pubescens, Empetrum nigrum, and Arctostaphylos uva-ursi) were planted in mulch pockets on mulch-covered and uncovered plots in summer 1996 in a highly polluted Scots pine stand in southwest Finland. Spreading a mulch layer on the soil surface was essential for the recolonization of natural vegetation and increased dwarf shrub survival, partly through protection against drought. Despite initial mortality, transplant establishment was relatively successful during the following 10 yr. Tree species had higher survival rates, but the dwarf shrubs covered a larger area of the soil surface during the experiment. Especially E. nigrum and P. sylvestris proved to be suitable for revegetating heavy metal" polluted and degraded forests. Natural recolonization of pioneer species (e.g., Epilobium angustifolium, Taraxacum coll., and grasses) and tree seedlings (P. sylvestris, Betula sp., and Salix sp.) was strongly enhanced on the mulched plots, whereas there was no natural vegetation on the untreated plots. These results indicate that a heavy metal" polluted site can be ecologically remediated without having to remove the soil. Household compost and woodchips are low-cost mulching materials that are suitable for restoring heavy metal"polluted soil.