Impacts of recent climate change on crop yield can depend on local conditions in climatically diverse regions of Norway

Globally, climate change greatly impacts the production of major crops, and there have been many attempts to model future yields under warming scenarios in recent years. However, projections of future yields may not be generalisable to all crop growing regions, particularly those with diverse topography and bioclimates. In this study, we demonstrate this by evaluating the links between changes in temperature and precipitation and changes in wheat, barley, and potato yields at the county-level during 1980–2019 in Norway, a Nordic country with a range of climates across a relatively small spatial scale. The results show that the impacts of climate variables on yield vary widely by county, and that for some crops, the strength and direction of the link depends on underlying local bioclimate. In addition, our analysis demonstrates the need for some counties to focus on weather changes during specific crucial months corresponding with certain crop growth stages. Furthermore, due to the local climatic conditions and varying projected climate changes, different production opportunities are likely to occur in each county.publishedVersio

Wooded hay meadows as viable production systems in sustainable small-scale farming

Wooded hay meadows provide livestock fodder in the form of both foliage from pollarded trees and hay from the understorey, and can be part of an environmentally friendly agroforestry system. However, trees may also have a negative effect on fodder production. Such trade-offs between productivity and sustainability in farming are poorly understood, especially in high-latitude areas. We studied hay production in two sites in the same wooded meadow in western Norway, one restored 6 years earlier than the other, to examine whether there were differences in hay production over a 4-year pollarding cycle. We measured production in transects starting from the trunks of pollarded and non-pollarded (reference) trees and running out into open meadow, and transects entirely in open meadow. We examined whether pollarding influenced hay production, and whether hay production was related to the distance from the tree trunk. Total production differed between the two sites, indicating that both time since restoration and differences in overall tree influence affected hay production. We observed a strong and immediate pollarding effect (increase in hay production) due to reduced tree influence. Trees have a negative influence on production as demonstrated by the increase in hay production with increasing distance from the tree trunk. However, additional dry fodder produced by harvesting leaves from pollarded trees more than compensates for reduction in hay production under pollarded trees. Moreover, the understorey production in the wooded hay meadow is at the same level as fertilized meadows in Norway when we include the fodder consumed by sheep during spring and autumn grazing. A wooded hay meadow is an environmentally friendly production system that does not compromise food production. Its tree component can also play an important role in climate change adaptation and mitigation, and supports higher biodiversity than industrial food production systems. Canopy cover, Management, Plantplant interactions, Pollarding, Production,Tree-influencepublishedVersio

Junipers enable heavily browsed rowan saplings to escape ungulates in boreal forest

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Distribution and ecology of Trichocolea tomentella in Norway

The liverwort Trichocolea tomentella is known from 65 localities in southern Norway. Almost half of these are in Hordaland county in Western Norway. T. tomentella has been observed at many localities (42%) in the last decade. On the other hand it has not been observed at 23% of the previously known localities after 1950, although a complete re-survey has not been performed. The species seems to be thriving in its main distribution centre in Western Norway, but in southeastern Norway urbanisation and modern forestry are major threats. In this part of Norway the species has probably gone extinct or is on its way to extinction at several of the localities. To preserve the species logging and draining close to springs, streams and gullies should be ceased. This will also preserve habitats that are species rich, in particular in bryophytes.Distribution and ecology of Trichocolea tomentella in NorwaypublishedVersio

Environmental Restoration in Hydropower Development — Lessons from Norway

Hydropower is expanding globally and is regarded a keymeasure formitigating climate change, but it also results inmajor environmental degradation, both at local scale andmore widely. We can learn lessons about how restoration can be used to alleviate these problems from failures and successes in countries with a long history of hydropower development, such as Norway. Here, hydropower projects grew larger over time, and in the 1960s, the emerging environmentalistmovement started to challenge hydropower developments because of their negative impacts on the environment. The NorwegianWater Resources and Energy Directorate then appointed a landscape architect who became very influential, particularly due to his skills in aesthetics and photo documentation. He developed principles for designing self-sustaining environments which he called “living nature”, and in particular proposed methods of restoring barren, unattractive, alpine spoil heaps. Later, restoration methods and goals have changed in response to new insights and the changing goals of ecological restoration. Here, we present current best practice for the alpine biome and sumup general lessons in three points: restoration can represent a sustainable, ‘third way’ in the conflict between conservation and development; including a wider group of professionalsmay improve restoration goals andmethods, and effective use of visual communication can be a good way of gaining support for new restoration principles.publishedVersio

Infrequent sporophyte production maintains a female-biased sex ratio in the unisexual clonal moss Hylocomium splendens

P>1. Sex ratios in unisexual bryophytes are most often female biased, whereas male-biased sex ratios predominate in unisexual seed plants. This 'bryophyte paradox', i.e. that sex ratios are biased in favour of the sex associated with the highest reproductive costs, has remained unexplained. 2. Analysis of sex-ratio patterns via the influence of sex distribution on population growth rates (lambda) has not previously been carried out for bryophytes. We used this method to model how variation in sex ratio and sporophyte frequency influences lambda in the clonal bryophyte Hylocomium splendens. We obtained lambda by matrix modelling of synthetic experimental populations derived from demographic field data, using a linear two-sex model. 3. In our set of experimental populations lambda varied between 1.13 and 1.27 in response to variation in sex ratio and sporophyte frequency, with the highest lambda obtained for the combination of a very low sporophyte frequency and a slightly female-biased sex ratio. 4. Our results explain the female-biased sex ratio of H. splendens by the slightly lower survival of and production of vegetative offspring by males than by non-sporophytic females. 5. Synthesis. According to our models, female dominance is the predicted outcome of low to moderate fertilization success and male performance intermediate between that of sporophytic and of non-sporophytic females. Our results therefore explain how a female-biased sex ratio can be maintained despite higher costs of reproduction in females than in males. In dioecious bryophytes, males and females must grow in close contact for fertilization to take place. Better performance of male ramets than of the female ramets they fertilize also explains how male clones can expand into female clones. A similar performance hierarchy of males and females may occur in unisexual clonal seed plants, but more efficient fertilization systems by pollination prevents the selective advantage of unfertilized females from being realized. This explains why vascular plant populations tend to be male biased. We hypothesise difference in fertilization distance range between sperm and pollen as a simple explanation why ramet level sex ratios are in general male dominated in clonal seed plants and female dominated in clonal bryophytes

Red deer mediate spatial and temporal plant heterogeneity in boreal forests

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Biologisk mangfold i bunnvegetasjonen i gransumpskog

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