Hopp til hovedinnholdet

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.

2025

Til dokument

Sammendrag

The growing hotel and education sectors in Ethiopia face increasing waste and energy demands, necessitating effective waste management and energy use strategies. This study is aimed to investigates biowaste production and energy consumption in hotels and university campuses in Southern Ethiopia, focusing on sustainable solutions for reducing environmental impacts. A mixed-methods approach, including surveys and onsite measurements, were used to assess energy consumption, biowaste generation, and management practices. A stratified purposive sampling was employed to select institutions, and both descriptive and inferential statistics, including time series analysis, multiple regression models, were applied; the environmental footprint of energy sources and energy potentials of biowastes were quantified following the guidelines set by the Intergovernmental Panel on Climate Change (IPCC).The study found that the primary energy sources for both sectors are electricity, natural gas/LPG, diesel fuel, fuelwood, and charcoal, with electricity being the dominant source. Hotels exhibit a consistent increase in energy consumption from 2016 to 2023, driven by tourism and service expansion, while university campuses show more fluctuating trends influenced by student enrollment and policy changes. Both sectors generate substantial biowaste annually—over 588 tons from hotels and 1448 tons from campuses—comprising food, fruit, vegetable and animal waste. However, waste management practices are often inadequate, with open dumping being common and the lack of energy recovery or treatment systems. The study quantified the greenhouse gas (GHG) emissions, found that non-electric energy sources such as oil fuels and firewood contribute significantly to CO2 emissions. In 2023, oil fuels accounted for 15,474.2 tonnes of CO2e, and firewood generated 130,377.2 tonnes CO2e, highlighting the need for cleaner energy alternatives to reduce emissions and reliance on carbon intensive energy sources.

Til dokument

Sammendrag

Arctic food systems blend Traditional Ecological Knowledge with modern, often energy-intensive influences, triggered by colonization. Food systems’ future depends on alignment of tradition with innovation, facilitation of resilience and a heritage-driven interaction with the global economy – at a pace determined by local communities.

Til dokument

Sammendrag

Small, forested catchments are prototypes of terrestrial ecosystems and have been studied in several disciplines of environmental science over several decades. Time series of water and matter fluxes and nutrient concentrations from these systems exhibit a bewildering diversity of spatiotemporal patterns, indicating the intricate nature of processes acting on a large range of time scales. Nonlinear dynamics is an obvious framework to investigate catchment time series. We analyzed selected long-term data from three headwater catchments in the Bramke valley, Harz mountains, Lower Saxony in Germany at common biweekly resolution for the period 1991 to 2023. For every time series, we performed gap filling, detrending, and removal of the annual cycle using singular system analysis (SSA), and then calculated metrics based on ordinal pattern statistics: the permutation entropy, permutation complexity, and Fisher information, as well as their generalized versions (q-entropy and α-entropy). Further, the position of each variable in Tarnopolski diagrams is displayed and compared to reference stochastic processes, like fractional Brownian motion, fractional Gaussian noise, and β noise. Still another way of distinguishing deterministic chaos and structured noise, and quantifying the latter, is provided by the complexity from ordinal pattern positioned slopes (COPPS). We also constructed horizontal visibility graphs and estimated the exponent of the decay of the degree distribution. Taken together, the analyses create a characterization of the dynamics of these systems which can be scrutinized for universality, either across variables or between the three geographically very close catchments.

Sammendrag

Climatic drought and changes in precipitation patterns are key features of the ongoing and predicted climatic changes in northern latitudes such as the boreal forest of Norway. Recent droughts highlight on the possible difficult future of spruce forests in southern Norway. To better understand and monitor these forests under a more extreme climate, it is crucial to gain a better understanding of the water relations of spruce trees across forest stands. Sap flow sensors are typically used for directly measuring the water demands for transpiration in individual trees. There are however limitations to their use in examining the hydraulic and physiological responses to extreme water supply variability: i) manufactured high-resolution sensors such as those following the Heat Ratio Method (HRM) or Heat Field Deformation (HFD) are expensive, limiting their deployment to a few trees in a stand, and ii) the sap flow sensors only measure the movement of water within the active sapwood, not accessing other physiological mechanisms and responses (radial growth, water storage) associated with stress response. Point dendrometers have become increasingly used, monitoring sub-daily stem size fluctuations resulting from both seasonal patterns of radial growth increment and the dynamics of plant tissue water balance. Manufactured point dendrometers are much cheaper to buy and easier to install and maintain than manufactured sap flow sensors. They can therefore be much more extensively deployed across forest stands. We aimed to analyse the relationship between sub-daily stem diameter changes and sap flow using point dendrometers and HRM sap flow sensors installed in a Norway spruce forest located 50 km north of Oslo, Norway. We linked these relationships with individual tree physical attributes, meteorology and soil climate over two growing seasons in 2022 and 2023. Our goal was to assess whether a predictive model of sap flow could be built from measured diameter changes, tree properties and climate, to ultimately reduce the uncertainty of stand level transpiration estimation at the daily resolution across entire forest stands.