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.
2024
Forfattere
Sanjana De Zoysa Jeewanthi Sirisena Helani Perera Shalinda Fernando Miyuru Gunathilake Upaka RathnayakeSammendrag
Rainfall Intensity Duration Frequency (IDF) curves can be identified as a major role in the planning of urban drainage infrastructure. Sri Lanka, which is an island surrounded by the Indian Ocean, is frequently exposed to various climatic alterations. Sri Lanka has specific region-wise IDF relationships for the entire country, however, these IDF curves were developed more than 30 years ago. Many in-situ rainfall observations in Sri Lanka have insufficient record lengths and the absence of finer time scale records (e.g. 15 min, hourly) leading to unreliable IDF curve developments. Given this importance, the present paper demonstrates the application of Satellite-based Precipitation Product (SbPP) daily rainfall in developing IDF curves for Sri Lanka. Rainfall satellite estimates derived from Integrated Multi-satellite Retrievals for GPM (IMERG), Tropical Rainfall Measuring Mission (TRMM-3B42), and Precipitation Estimation from Remotely Sensed Information Using Artificial Neural Networks – Climate Data Record (PERSIANN-CDR) have been used to evaluate the ability of application of remote sensing data to develop IDF curves for Sri Lanka against rain gauge (RG) data. Our study breaks new ground by generating 50 IDF curves tailored to specific locations covering the whole county Sri Lanka, using daily rainfall data from RGs and three SbPPs during the period between 1990 and 2019. This marks a significant departure from the conventional approach, offering a more granular understanding of rainfall patterns in the country. By providing IDF curves for individual locations, our research presents a novel contribution to Sri Lanka's IDF history. At first, to evaluate the accuracy of SbPPs, statistical analysis was conducted using continuous and categorical evaluation indices. Second, IDF curves were developed and compared with the presently available IDF curves. Results showcased that IMERG outperformed all SbPPs, while PERSIANN-CDR showed dire performances. The IMERG and TRMM-3B42 products tend to overestimate light precipitation regions in high elevations and overestimate heavy rainfall in low elevations compared to rain gauge data. Rainfall intensities derived by rain gauge data depicted relative changes within ±30% for shorter durations and ±20% for longer durations while SbPPs showed beyond ±30% difference concerning the previously developed IDFs. It was apparent that these products have significant inaccuracies which cannot be neglected when utilizing them in developing IDF curves. This study will be beneficial in solving design problems associated with urban runoff control and disposal where knowing the rainfall intensities of different return periods with different durations is vital.
Forfattere
May Bente BrurbergSammendrag
Det er ikke registrert sammendrag
Sammendrag
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Sammendrag
Female flowering and cone production took place in three Norway spruce progeny tests at ages 17 and 20 years, each planted with full-sib families from a half diallel. The number of cones on individual trees were scored in five classes. More than 50 % of the trees produced cones, and a considerable variation was found among families for the ability to produce cones (precocity) and for the number of clones scored in classes (fruitfulness). Both traits were strongly related to tree heights and diameters at the individual and at the family level. In general, tall trees produced the highest number of cones. However, some families produced many cones even if their average heights were low. In two of the half diallels, estimates of GCA variance components for the number of cones produced had twice the value of the SCA component, indicating additive genetic inheritance of cone production. Heritability estimates of cone scores were 0.10, 0.17 and 0.23, and the genetic correlations between cone production and tree heights were 0.40, 0.50 and 0.35 in the three half-diallels, respectively.
Forfattere
Jaime Puértolas Pedro Villar-Salvador Enrique Andivia Ishita Ahuja Claudia Cocozza Branislav Cvjetković Jovana Devetaković Julio J. Diez Inger Sundheim Fløistad Petros Ganatsas Barbara Mariotti Marianthi Tsakaldimi Alberto Vilagrosa Johanna Witzell Vladan IvetićSammendrag
Drought hardening is a nursery technique aimed to enhance early forest plantation establishment under dry conditions, which is a main limiting factors for plantation success. However, the quantitative effectiveness of drought hardening remains unclear. We conducted a meta-analysis to evaluate the influence of different factors in the effectiveness of drought hardening on seedling post-planting survival and growth. Overall, drought hardening did not significantly affect survival or growth, as several factors induced great heterogeneity, but analyses of those factors explained its effectiveness, especially on survival. A longer time between hardening and transplanting strongly reduced survival. Indoor-grown seedlings did not benefit more from hardening than outdoor-grown seedlings. Evaluations of drought hardening effectiveness in pots showed positive effects on survival but negative effects on growth, while no effects were found in large bed experiments. In field experiments, hardening significantly increased survival and growth with site aridity. Survival benefits were independent of species drought tolerance, measured by osmotic potential at the turgor loss point (πtlp), in moderate to high aridity sites. However, in low aridity sites, hardening increased survival in drought-tolerant species but decreased it in drought-intolerant species. Field results showed that hardening benefited shrubs more than trees in angiosperms. In conclusion, drought hardening at the end of nursery cultivation tend to increase post-planting seedling performance particularly in scenarios limiting post-planting root growth such as in arid climates and pot experiments. Our findings highlight the importance of future research on modelling the interaction between these technical features and species water use strategies..
Sammendrag
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Forfattere
Jorunn Børve Katharina Pampus Tuuli Haikonen Andrea Podavkova Gaute Myren Roland W. S. WeberSammendrag
Ascospores discharged at rainfall and dispersed by wind can provide long-distance spread of the European canker fungus, Neonectria ditissima. Ascospores are produced by perithecia which are the sexual reproductive stage. Diffuse knowledge exists on the seasonal pattern of perithecium formation under different climatic conditions. Therefore, the development of perithecia was observed for several successive seasons at five sites in three Northern European countries. In Norway and Finland, ripe perithecia were commonly recorded throughout the year, and on individual cankers continuously for up to 28 months. In contrast, asexual reproductive structures (sporodochia) were confined to the growing season in both countries. In Northern Germany an average of 51% of cankers developed ripe perithecia by late winter, and perithecial senescence ensued in late spring. On average, ripe perithecia were present on cankers for 22 weeks. In contrast, sporodochia were observed all year round. The timing of perithecium maturation correlated with the number of days with > 2 mm rainfall in July–September. The presence of mature perithecia and sporodochia for different lengths of time in different countries has implications for regional disease management strategies.
Sammendrag
Sommeren 2023 utlyste Vestfold og Telemark fylkeskommune, sammen daværende Viken fylkeskommune, en tilbudskonkurranse om å utarbeide en digital kartløsning som synliggjør naturlige økosystemtjenester. Kartløsningen er laget for kommunene Sandefjord, Larvik, Porsgrunn, Skien, Notodden, Nome, Ringerike, Aurskog-Høland, Rælingen og Moss. Hensikt med oppdraget er å se klimagassutslipp, klimatilpasning og naturmangfold i sammenheng for å styrke betydningen av grønnstruktur og økosystemer i arealbruksvurderinger. NIBIO har laget en rekke temakart som synliggjør økosystemtjenestene. Denne rapporten gjør rede for temakartene, datagrunnlaget og bruksmåter.
Sammendrag
Det er ikke registrert sammendrag
Forfattere
Julian Helfenstein Samuel Hepner Amelie Kreuzer Gregor Achermann Tim Williams Matthias Bürgi Niels Debonne Thymios Dimopoulos Vasco Diogo Wendy Fjellstad Maria Garcia-Martin Józef Hernik Thanasis Kizos Angela Lausch Christian Levers Jaan Liira Franziska Mohr Gerardo Moreno Robert Pazur Tomasz Salata Beatrice Schüpbach Rebecca Swart Peter H. Verburg Anita Zarina Felix HerzogSammendrag
Current agricultural practices in Europe are increasingly aggravating societal and environmental safety concerns. This creates social and regulatory pressures on farmers, which can lead to declining material and social status of farmers, farmer discontent, and anti-regulation protests. These tensions are rooted in conflicting value systems for agricultural development, which can range from productivist pathways (i.e. valuing production above all else) to increasing multifunctionality pathways (i.e. valuing agriculture for its contribution to multiple economic, environmental and societal needs). It is largely unknown to what degree individual farms and agricultural landscapes are transitioning towards increasing productivism or multifunctionality in practice. Here, we mapped landscape changes and interviewed farmers (n = 274) to examine the diversity of agricultural development pathways in 17 study sites across Europe over the last 20 years (2000–2020). We also assessed the associations between the development pathways and farmers’ perceptions of socio-economic outcomes, namely job satisfaction, societal valuation, and economic performance. Farm-level development was largely aligned with productivist pathways, while landscape-level changes aligned more closely with an increasing multifunctionality pathway. Farmers on pathways of increasing multifunctionality did not perceive improved outcomes on livelihood indicators as compared to productivist farmers. Furthermore, farms on increasing multifunctionality pathways were concentrated in sites with very high management intensities that face strong pressure from environmental regulations, as well as low-intensity, mountainous sites, where opportunities for intensification are limited. These results suggest that current pathways that increase multifunctionality arise mostly by necessity. Successful agricultural transformation will therefore require policy to create enabling environments that provide socioeconomic benefits for farmers to increase multifunctionality, and a civil society and market conditions that value sustainable agriculture.