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.
2021
Abstract
No abstract has been registered
Abstract
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Authors
Milan Flach Alexander Brenning Fabian Gans Markus Reichstein Sebastian Sippel Miguel D. MahechaAbstract
Drought and heat events affect the uptake and sequestration of carbon in terrestrial ecosystems. Factors such as the duration, timing, and intensity of extreme events influence the magnitude of impacts on ecosystem processes such as gross primary production (GPP), i.e., the ecosystem uptake of CO2. Preceding soil moisture depletion may exacerbate these impacts. However, some vegetation types may be more resilient to climate extremes than others. This effect is insufficiently understood at the global scale and is the focus of this study. Using a global upscaled product of GPP that scales up in situ land CO2 flux observations with global satellite remote sensing, we study the impact of climate extremes at the global scale. We find that GPP in grasslands and agricultural areas is generally reduced during heat and drought events. However, we also find that forests, if considered globally, appear in general to not be particularly sensitive to droughts and heat events that occurred during the analyzed period or even show increased GPP values during these events. On the one hand, normal-to-increased GPP values are in many cases plausible, e.g., when conditions prior to the event have been particularly positive. On the other hand, however, normal-to-increased GPP values in forests may also reflect a lack of sensitivity in current remote-sensing-derived GPP products to the effects of droughts and heatwaves. The overall picture calls for a differentiated consideration of different land cover types in the assessments of risks of climate extremes for ecosystem functioning.
Abstract
The scope of this study was to provide an update on fluoride (F) emission effects on vegetation around three aluminium smelters. We visited Årdal and Sunndal smelters in 2019-2020 and Mosjøen in 2020, assessed and documented the visual symptoms of F-damage on vegetation and related these to detected values of F in plant tissue. Three plant species showed qualities as useful indicators: Rowan, pine and St. John’s wort. Because male-fern accumulated extreme F-values and showed clear grazing damage, the monitoring of this species may be warranted because of the potential health hazard for the grazing animals. In Årdal and Sunndal, during 2019 and 2020, we detected the highest F-values in male-fern, ranging from 94 to 925 mg F/kg. In rowan, the highest F-concentration was detected in trees growing within the Årdal smelter (1161 mg F/kg) but on all other locations the F-concentrations in rowan ranged from 4 to 327 mg F/kg. In pine, the F-concentrations ranged from 6-351 mg F/kg for all needle ages, but older needles always accumulated more F than younger ones. In St. John’s wort the accumulated F-values ranged from 10-84 mg F/kg. At all smelters there was a gradient of decreasing F-concentration in vegetation with increasing distance from the smelter. F-emissions in Årdal (12 and 11 kg F/hour in 2019 and 2020, respectively) and in Sunndal during 2019 (12 kg F/hour) were only slightly higher than the recommended limits (10 kg F/hour) for damage on vegetation, while in Mosjøen the F-emissions were 7 kg F/hour in 2020. The presence of F-damage on vegetation was consistent with the reported emission-levels. On basis of this evaluation, reductions in emissions are still advisable in Årdal and Sunndal, while the situation is acceptable in Mosjøen.
Authors
Michel VerheulAbstract
No abstract has been registered
Abstract
Spondylosis deformans is a spinal disease common to several dog breeds, and several treatments including veterinary chiropractic may be used to treat affected dogs. Little is known, however, about the efficacy of chiropractic treatment as precautionary measure, aiming to reduce the probability of spondylosis development. We performed a randomized study where one half of the Boxer puppies from 17 litters were given veterinary chiropractic treatment at monthly intervals from eight weeks of age until they were one year old, while the other half were given no treatment (treated: n = 44, controls: n = 43). At an age of one year, spondylosis occurrence was recorded based on a scoring of X-ray images of the spine. The frequency of occurrence was significantly lower (p = 0.0478) in the treated dogs (25.0%) than in the controls (46.5%). We also tested if spondylosis occurrence in the treated dogs correlated with the average number of spinal joints with decreased mobility found per chiropractic treatment. No such effect was found, however. In summary, our results suggest that veterinary chiropractic treatment may be successfully used to reduce the probability of early development of spondylosis in young Boxers.
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No abstract has been registered
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No abstract has been registered
Authors
Jogeir N. StoklandAbstract
This study documents volume increment and natural mortality in 1379 old boreal forests plots during four consecutive inventory cycles in the Norwegian national forest inventory. The stands age up to 100 years beyond recommended rotation length (close to economical optimal rotation length) and comprise a wide range of site productivity classes in both pine- and spruce-dominated forests. The annual gross volume increment was stable and nearly constant up to 50–100 years beyond economically optimal rotation length. In parallel, there was very low natural mortality (0.22–0.66% of standing volume) with minimal risk of stand collapse. Stands with satisfactory stocking had volume increment equal to or higher than the reference volume increment in managed stands harvested at recommended rotation length, while poorly stocked stands had inferior volume increment. From a climate change mitigation perspective, it seems to be a good strategy to extend the rotation length beyond what is currently recommended, provided that the stands have satisfactory stocking.
Abstract
No abstract has been registered