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.
2021
Forfattere
Jan Pisek Angela Erb Lauri Korhonen Tobias Biermann Arnaud Carrara Edoardo Cremonese Matthias Cuntz Silvano Fares Giacomo Gerosa Thomas Grünwald Niklas Hase Michal Heliasz Andreas Ibrom Alexander Knohl Johannes Kobler Bart Kruijt Holger Lange Leena Leppänen Jean-Marc Limousin Francisco Ramon Lopez Serrano Denis Loustau Petr Lukes Lars Lundin Riccardo Marzuoli Meelis Mölder Leonardo Montagnani Johan Neirynck Matthias Peichl Corinna Rebmann Eva Rubio Margarida Santos-Reis Crystal Schaaf Marius Schmidt Guillaume Simioni Kamel Soudani Caroline VinckeSammendrag
Information about forest background reflectance is needed for accurate biophysical parameter retrieval from forest canopies (overstory) with remote sensing. Separating under- and overstory signals would enable more accurate modeling of forest carbon and energy fluxes. We retrieved values of the normalized difference vegetation index (NDVI) of the forest understory with the multi-angular Moderate Resolution Imaging Spectroradiometer (MODIS) bidirectional reflectance distribution function (BRDF)/albedo data (gridded 500 m daily Collection 6 product), using a method originally developed for boreal forests. The forest floor background reflectance estimates from the MODIS data were compared with in situ understory reflectance measurements carried out at an extensive set of forest ecosystem experimental sites across Europe. The reflectance estimates from MODIS data were, hence, tested across diverse forest conditions and phenological phases during the growing season to examine their applicability for ecosystems other than boreal forests. Here we report that the method can deliver good retrievals, especially over different forest types with open canopies (low foliage cover). The performance of the method was found to be limited over forests with closed canopies (high foliage cover), where the signal from understory becomes too attenuated. The spatial heterogeneity of individual field sites and the limitations and documented quality of the MODIS BRDF product are shown to be important for the correct assessment and validation of the retrievals obtained with remote sensing.
Forfattere
Marit Skuterud VennatrøSammendrag
Formålet med kartleggingsprogrammet «Skadegjørere i potet» er å få kunnskap om status med hensyn til forekomst av planteskadegjørerne lys ringråte (Clavibacter michigaensis spp.), mørk ringråte (Rastonia solancearum), rotgallnematodene Meloidogyne chitwoodi og M. fallax samt potetkreft (Synchytrium endobioticum) i norsk produksjon av mat- og industripotet. Denne rapporten omhandler status for rotgallnematodene. Rotgallnematoder (Meloidogyne spp.) er en stor gruppe obligate planteparasittære som finnes over hele verden. Skadene etter rotgallnematoder forringer både kvalitet og avling, og gir store avlingstap på verdensbasis. M. chitwoodi og M. fallax har mange vertsplanter, og er vanskelige å bekjempe dersom de etablerer seg. Derfor ansees disse artene som alvorlige planteskadegjørere, og som en trussel mot europeisk potet og gulrot produksjon. Både M. chitwoodi og M. fallax er påvist i Europa i begrenset omfang. Begge artene de senere årene funnet i Sverige. M. chitwoodi og M. fallax er ikke påvist i Norge, men det er risiko for at begge artene kan etablere seg og gjøre omfattende skade i norsk potet- og gulrotproduksjon….
Forfattere
Irina Herzon Kaisa J. Raatikainen Sølvi Wehn Solvita Rūsiņa Aveliina Helm Sara A. O. Cousins Valerijus RašomavičiusSammendrag
The European continent contains substantial areas of semi-natural habitats, mostly grasslands, which are among the most endangered habitats in Europe. Their continued existence depends on some form of human activity, for either production or conservation purposes, or both. We examined the share of semi-natural grasslands within the general grassland areas in boreal Europe. We reviewed research literature across the region to compile evidence on semi-natural grasslands and other semi-natural habitats, such as wooded pastures, in respect to a range of topics such as ecology, land-use change, socioeconomics, and production. We also explored drivers of the research agenda and outlined future research needs. Challenges are faced when defining and quantifying semi-natural habitats even across a restricted region. Agricultural development and other policies clearly impact the research agenda in various countries. There are recent signs of a shift from classical ecological studies toward more multidisciplinary and integrated research. To sufficiently address the threats faced by semi-natural habitats, political and research frameworks in the European Union should pay more attention to the social-ecological complexity inherent in their management and should support the engagement of various actors into participatory governance processes. This is in line with a full-farm approach implicit in high nature value farming systems.
Sammendrag
In the last century, local or individual-based forest management was introduced by various forest scientists including Schädelin, Abetz and Pollanschütz as an alternative to traditional global thinning methods. They suggested breaking large forest stands down into smaller neighbourhood-based units. The centre of each of these neighbourhood-based units is a frame tree (also referred to as final crop tree, elite tree or target tree) with clearly defined properties that depend on the management objectives. In each management intervention, trees in the neighbourhood of frame trees that in the next 5–10 years are likely to influence the frame trees negatively are removed selectively. In contrast to global methods, management is only carried out where there are frame trees. Local or individual-based forest management methods were first introduced in a commercial forestry context, but rather constitute generic methods that can be efficiently applied in management for conservation, carbon sequestration and recreation. They are also often applied in the context of continuous cover forestry (CCF). In this study, we analysed the behaviour of test persons selecting frame trees in 26 training sites, so-called marteloscopes, from all over Great Britain. Although the test persons were new to individual-based management, statistical performance indicators suggested that frame trees were selected in accordance with the theory of local or individual-based forest management. Unexpectedly the test persons even achieved a comparatively high degree of agreement. This result contrasts the low agreement and partly unsatisfying performance indicators incurred in the selection of frame-tree competitors, the second step of local forest management. The outcomes of this study highlight that training in individual-based forest management needs to put more emphasis on the identification of frame-tree competitors.
Sammendrag
In developing countries, over 50% of horticultural crops are lost after harvesting due to absense of or poor postharvest cold storage facilities. Cold storage facility is a critical component of the food supply chain and food security because it can extend the storage period of the perishable products; avoid glut and post-harvest losses, reducing transport bottlenecks. The objective of the study was to design and construct an evaporative cooling system to store horticultural products in a wide range of climatic conditions in Ethiopia. The design integrates direct evaporative cooling system and indirect evaporative cooling system with technical improvements and re-arrangements for continuous operation and handling purpose. After the design and construction work of the cooler was completed, its performance was tested and evaluated without product load at maximum mean annual temperature for five days. Finally, the performance and effect of the cooler on tomato shelf life and quality was evaluated by storing fresh tomatoes inside the cooler shelves. For comparison (control group), randomly selected fresh tomatoes were stored in a basket, which is a standard method that retailer display tomatoes in the market in the study area. A portable evaporative cooler was constructed from locally available and used materials and integrated with new temperature and relative humidity sensors. It had a capacity of 260 Kg (573.2 lb). The evaporative cooler resulted in a reduction in the maximum ambient temperature from 32.8°C (91.6°F) to 23.5°C (74.3°F) in the cooler. As the ambient temperature drops to 21.8°C (71.4°F), the temperature in the cooler reduced to 15°C (59°F). The cooler stabilized the relative humidity between 77- 88%. The newly designed and constructed evaporative cooler reduced the postharvest loss of tomato from 80 % in a traditional basket to 5% in the evaporative cooler. The cooler reduced the postharvest loss of tomato by 94%. It maintained the quality of the fresh tomatoes. In conclusion what we showed in this study was that we have refined the design and constructed a low cost and effective cooling system that can be used by poor retailers of vegetables and fruits. Evaporative cooler is an old and forgotten technology, if the design and construction are refined, it can be used to regulate temperature and relative humidity and used in different purposes especially for those who cannot afford to buy modern thermal regulation technologies.
Sammendrag
Proximal sensing technologies are becoming widely used across a range of applications in environmental sciences. One of these applications is in the measurement of the ground surface in describing soil displacement impacts from wheeled and tracked machinery in the forest. Within a period of 2–3 years, the use photogrammetry, LiDAR, ultrasound and time-of-flight imaging based methods have been demonstrated in both experimental and operational settings. This review provides insight into the aims, sampling design, data capture and processing, and outcomes of papers dealing specifically with proximal sensing of soil displacement resulting from timber harvesting. The work reviewed includes examples of sensors mounted on tripods and rigs, on personal platforms including handheld and backpack mounted, on mobile platforms constituted by forwarders and skidders, as well as on unmanned aerial vehicles (UAVs). The review further highlights and discusses the benefits, challenges, and some of the shortcomings of the various technologies and their application as interpreted by the authors. The majority of the work reviewed reflects pioneering approaches and innovative applications of the technologies. The studies have been carried out almost simultaneously, building on little or no common experience, and the evolution of standardized methods is not yet fully apparent. Some of the issues that will likely need to be addressed in developing this field are (i) the tendency toward generating apparently excessively high resolution micro-topography models without demonstrating the need for or contribution of such resolutions on accuracy, (ii) the inadequacy of conventional manual measurements in verifying the accuracy of these methods at such high resolutions, and (iii) the lack of a common protocol for planning, carrying out, and reporting this type of study.
Sammendrag
It is not known to what degree growth and fruit yield are source-limited in everbearing strawberry plants. The growth and yield performance effect of bi-weekly removal of all runners and/or one or two leaves during the cropping season of tunnel-grown ‘Favori’ everbearing strawberry plants was determined. Plants were grown on a table-top system in an open plastic tunnel under natural light conditions in Norway from May to October. Removal of runners and leaves was bi-weekly from 5 June until 25 September. Fruits were harvested from 5 July to 7 October. Bi-weekly runner removal increased total and marketable yield and number and size of fruits, while increasing leaf thinning had the opposite effects. However, none of the treatments affected the fruit number and yield of the first fruiting flush. The treatments did not affect realization of the yield potential of the plants at planting, whereas the continued floral initiation and fruit growth were enhanced by runner removal. Increasing leaf thinning had the opposite effects. Both floral initiation and fruit growth in heavily flowering and fruiting everbearing strawberry are source-limited owing to the high fruit/leaf ratio of such plants.
Forfattere
Ove BergersenSammendrag
Rapporten gir oversikt over oppdaterte analyser og kunnskap produsert, mottatt og vurdert i 2020. Data for luktregistreringer, sigevannsbehandling og grunnvann fra miljøbrønner i 2020 er vurdert sammen med tidligere data. Nye temperaturmålinger av rankene når de er blitt termofile (over 55 °C) i 4 uker viser fortsatt god prosess og sikker hygienisering gjennom 2020, også med ekstra vending. Analyser av evt. patogene mikroorganismer et utført i 2020 på kompostbatcher etter fase 2 er utført. Ingen total økning gjennom 2020 i registrering av lukt, selv om perioder i september til november med stabilt kaldt vær førte til flere hyppige registreringer. Registreringstall av lukt i nærmiljøet ble totalt 18 episoder i 2020, av disse 5 i sentrum av Skibotn. Antall registreringer av svak lukt dominerer. En økning i konsentrasjoner fra ny rensedam av urenset deponisigevann analysert kvartalsvis i 2020 ble observert. Vannanalyser gjennom 2020 av renset og infiltrert sigevann fra den nærmeste miljøbrønn 3 viste fortsatt ingen økning i konsentrasjoner av både næringsstoffer og metaller. Rensegraden fra sedimenteringsdam til miljøbrønn 3 har bedret seg i 2020. Det er ikke synlige forurensinger (rustbrune jernutfellinger) ved elvebredden av grunnvann som strømmer ut i Skibotnelva.
Forfattere
Geir Wæhler Gustavsen Helge Berglann Elisabeth Jenssen Signe Kårstad Divina Gracia P. RodriguezSammendrag
Urban agriculture is increasingly recognized as an important sustainable pathway for climate change adaptation and mitigation, for building more resilient cities, and for citizens’ health. Urban agriculture systems appear in many forms – both commercial and non-commercial. The value of the services derived from urban agriculture, e.g. enhanced food security, air quality, water regulation, and high level of biodiversity, is often difficult to quantify to inform policymakers and the general public in their decision making. We perform a contingent valuation survey regarding four different types of urban agriculture in Oslo. The citizens of Oslo are asked about their attitudes and willingness to pay for non-commercial and commercial urban agriculture. The non-commercial agriculture consists of urban community gardens for the citizens and urban gardens for work training, education and kindergartens. On the other hand, the commercial urban agriculture consists of aquaponics and vertical production. Results show that the citizens of Oslo are willing to increase their tax payments to contribute to further development of urban farming in Oslo. Keywords: Willingness to pay; community garden; aquaponics; vertical farming; Oslo
Sammendrag
Self-sufficiency with feed (SSF) is a basic principle in organic animal production. The current regulations do not impose strict requirements for SSF at farm level, but further restrictions are expected in future. The aim of the present work was to quantify SSF on a range of organic dairy farms in Norway and study farmers’ strategies to produce milk with a high degree of SSF. Nine farms were selected for interview and data collection. On farm level, the proportion of SSF varied between 66 and 99 %. SSF increased to 88-100 % when expressed on national level. Land area is among the limiting factors for famers to reach higher SSF while maintaining the milk production level. A lower proportion of concentrates in the diet seems to have as strong impact on SSF as using own cereals and protein crops as feed, but milk production per total feed production area was highest for the latter. The farmers’ goals and actions are important driving forces to develop more SSF in dairy production systems.