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.
2025
Abstract
No abstract has been registered
Authors
Lucas K. Johnson Zhiqiang Yang Angela Erb Ryan Bright Grant M. Domke Tracey S. Frescino Crystal B. Schaaf Sean P. HealeyAbstract
Reforestation is generally regarded as having the most substantial climate mitigation potential among a suite of available natural climate solutions which have focused almost exclusively on the benefits of carbon sequestration and storage. However, these reforestation studies have not accounted for the adverse warming impacts resulting from corresponding surface albedo change. A newly available dataset developed with albedo imagery from the Landsat 8 satellite analyzed at field plots from the United States (US) Forest Inventory and Analysis (FIA) program provides non-soil carbon stocks and corresponding carbon-equivalent albedo offsets for 30 distinct forest-type groups indexed by 10-year age bins. In this case study we leverage this new dataset in concert with FIA species distribution data to investigate reforestation scenario planning based on joint carbon-albedo estimates (non-soil carbon stock less a carbon-equivalent albedo offset) instead of just carbon storage estimates alone. Specifically, our analysis informs managers interested in planting optimal forest-type groups for climate change mitigation outcomes approaching the year 2050. We assist in one of the most fundamental steps in any reforestation project: deciding which forest type or tree species mix to plant. We present our results as forest-type group recommendations within 64,000 hectare hexagons as a means to offer localized guidance and to examine the spatial patterns of albedo impacts across the conterminous US. We found that albedo offsets were most impactful on decisions in the Northeastern regions of the US, where optimizing for joint carbon-albedo in the next 25-years implies planting deciduous forest-type groups (Maple/beech/birch) instead of otherwise carbon-optimal coniferous forest-type groups (White/red/jack pine). Although the consideration of albedo did not alter 25-year tree planting decisions in most of the US, it did reduce the expected climate benefit of reforestation in general. We provide a standalone application that ranks all forest-type groups detected by FIA within a given hexagon, allowing managers to evaluate alternatives in light of site-specific constraints. This paper describes a replicable case study for incorporating albedo offsets in reforestation plans. Similar analyses may be performed anywhere Landsat albedo data are available over adequate measurements of forest carbon stocks. Recommendations: • Albedo impacts on 25-year tree planting decisions are concentrated in the Northeastern regions of the United States, where considering albedo offsets together with carbon stocks implies planting the Maple/beech/birch forest-type group in place of the otherwise carbon-optimal White/red/jack pine group. • Our reforestation support application allows managers to explore localized forest-type group rankings on the basis of joint carbon-albedo benefits. • Fine-resolution albedo data, which is not currently a standard data product, provides more comprehensive support for reforestation projects intended to mitigate global climate change.
Authors
Jari Hynynen Narayanan Subramanian Clara Antón Fernandéz Soili Haikarainen Emma Holmström Micky Allen Saija Huuskonen Jouni Siipilehto Hannu Salminen Mika Lehtonen Kjell Andreassen Urban NilssonAbstract
We studied the ability of extended rotations as a measure to promote sustainable management ofproduction forests in Nordic countries. We carried out scenario analyses for three large forestregions in Southern Finland, Central Sweden, and South-Eastern Norway, where forestry has a highsocioeconomic value. We analyzed the effects on wood production, carbon sequestration, and theamount of produced deadwood over the 50 years. In the reference scenario (BAU), the prevailingmanagement of production forests was applied. In the scenario for extended rotations (EXT),rotation lengths were extended by 30 years, on average. We used data from national forestinventories to represent the current stage of the regions’ forests and produced future forecastsusing local models, which have been widely applied in large-scale analyses. The increase in carbonsequestration and production of deadwood in production forests can be achieved by lengtheningrotations but only at the expense of harvesting removals. The increase in annual carbonsequestration is between 0.7 and 1.6 Mg CO2 eq ha−1. Natural mortality increases by 20–30% alongwith the amount of deadwood by 0.15 m3 ha−1 a−1, on average. The decrease in the mean annualharvesting removals varies from 0.4 to 1.6 m3 ha−1 a−1 from region to region.
Authors
Andreas Hagenbo Lise Dalsgaard Marius Hauglin Stephanie Eisner Line Tau Strand O. Janne KjønaasAbstract
Boreal forest soils are a critical terrestrial carbon (C) reservoir, with soil organic carbon (SOC) stocks playing a key role in global C cycling. In this study, we generated high-resolution (16 m) spatial predictions of SOC stocks in Norwegian forests for three depth intervals: (1) soil surface down to 100 cm depth, (2) forest floor (LFH layer), and (3) 0–30 cm into the mineral soil. Our predictions were based on legacy soil data collected between 1988 and 1992 from a subset (n = 1014) of National Forest Inventory plots. We used boosted regression tree models to generate SOC estimates, incorporating environmental predictors such as land cover, site moisture, climate, and remote sensing data. Based on the resulting maps, we estimate total SOC stocks of 1.57–1.87 Pg C down to 100 cm, with 0.55–0.66 Pg C stored in the LFH layer and 0.68–0.80 Pg C in the upper mineral soil. These correspond to average SOC densities of 15.3, 5.4, and 6.6 kg C m−2, respectively. We compared the predictive performance of these models with another set, supplemented by soil chemistry variables. These models showed higher predictive performance (R2 = 0.65–0.71) than those used for mapping (R2 = 0.44–0.58), suggesting that the mapping models did not fully capture environmental variability influencing SOC stock distributions. Within the spatial predictive models, Sentinel-2 Normalized Difference Vegetation Index, depth to water table, and slope contributed strongly, while soil nitrogen and manganese concentrations had major roles in models incorporating soil chemistry. Prediction uncertainties were related to soil depth, soil types, and geographical regions, and we compared the spatial prediction against external SOC data. The generated maps of this offer a valuable starting point for identifying forest areas in Norway where SOC may be vulnerable to climate warming and management-related disturbances, with implications for soil CO2 emissions.
Abstract
In recent years, biochar loaded with urea has been proposed as a promising N-rich fertilizer with both high-N capacity and slow release. Understanding the interaction between urea and biochar at the molecular level is key to product design. Solid-state NMR (SSNMR) spectroscopy is a particularly powerful method to probe molecular composition and interactions within the bulk of materials. The objective of this work was to identify molecular structures and interactions when urea is loaded into and released from biochar. To do so, we carried out SSNMR investigations of biochar loaded with 13C and 15N isotopically enriched urea. Biochar-urea composites were prepared both with a saturated aqueous urea solution (BUs) and with molten urea (BUm). SSNMR analysis revealed that urea is predominantly in a paracrystalline form on the biochar surface or physically entrapped within biochar pores. In BUm, products of the thermal degradation of urea were also detected, mainly in the form of biuret. Water-immersion experiments showed that 78 and 64% of the urea contained in BUs and BUm is released, respectively, after 24 h, demonstrating substantial retention of urea. The residual urea is mainly physically confined in the biochar pores. In the case of BUm, urea thermal degradation species are also partially retained.
Abstract
Mitigation and adaptation are both urgently needed to effectively address climate change and reduce its effects. This is particularly pertinent in the agricultural sector, a major contributor to emissions and highly vulnerable to climate impacts. Our study investigates how farmers perceive and respond to mitigation and adaptation information. We develop and test animated video interventions in an incentivised survey experiment with Norwegian horticultural farmers (N = 513). We examine how an intervention framed in terms of mitigation (Mitigation treatment) or adaptation (Adaptation treatment) influenced support for sector-wide mitigation policies and actual adoption of a sustainable farming practice (cover crops). The results show that the Adaptation treatment significantly increased support for national agricultural mitigation policy compared to the Control, while the Mitigation treatment had no significant effect, suggesting that adaptation is not seen as a substitute for mitigation. However, neither treatment impacted the adoption of cover crops. These findings highlight the need for careful climate messaging in agriculture.
Abstract
Many countries have goals to reduce soil sealing of agricultural land to preserve food production capacity. To monitor progress, reliable data are needed to quantify soil sealing and changes over time. We examined the potential of the Imperviousness Classified Change (IMCC) 2015–2018 product provided by the Copernicus Land Monitoring Service (CLMS) to assess soil sealing in agricultural areas in Poland and Norway. We found very high overall accuracy due to the dominance of the area with no change. When we focused on areas classified as change, we found low user accuracy, with over-estimation of soil sealing. The producer accuracy was generally much higher, meaning that real cases of soil sealing were captured. This is better than under-estimation of soil sealing because it highlights areas where sealing may have occurred, allowing the user to carry out further control of this much smaller area, without having to assess the great expanse of unchanged area. We concluded that the datasets provide useful information for Europe. They are standardized and comparable across countries, which can enable comparison of the effects of policies intended to prevent soil sealing. Some distinctions between classes are not reliable, but the general information about increase or decrease is useful.
Abstract
This chapter explores the implementation of the smart city idea in Stavanger Municipality. While smart city ideas are internationally varyingly defined, Stavanger co-developed and adopted a local and national roadmap for smart city implementation in the municipality. This qualitative case study explores how the office, established for the smart city implementation in Stavanger, coped with the implementation process in practice, considering respectively rational, natural, new institutional, and translation theory perspectives of organizational change. Data were collected from spring 2019 to spring 2020, employing qualitative interviews and document analyses of semi-annual reports (2018–2019), to explore the research question: What happened with smart city ideas under their implementation in the Stavanger Municipality, in view of selected organizational change theory? The data were analyzed by applying pre-elaborated theory-derived checkpoints. Findings indicate that the Stavanger Municipality seems to have implemented the smart city idea during processes strongly related to established organizational culture. During various stages of the process, each of the considered organizational change theories were reflected, dependent on the time of evaluation, culminating in the establishment of translation competence in the organization. The study’s findings and view of understanding may inspire and critically prepare other medium-sized urban municipalities on their way to becoming smart cities.
Authors
Vilde Lytskjold Haukenes Johan Asplund Line Nybakken Jørund Rolstad Ken Olaf Storaunet Mikael OhlsonAbstract
A key property of the boreal forest is that it stores huge amounts of carbon (C), especially belowground in the soil. Amounts of C stored in the uppermost organic layer of boreal forest soils vary greatly in space due to an interplay between several variables facilitating or preventing C accumulation. In this study, we split C stocks into the organic layer and charcoal C due to their difference in origin, stability, and ecological properties. We compared organic layer C and charcoal C stocks in two regions of south-central Norway (Trillemarka and Varaldskogen), characterized by Scots pine and Norway spruce forests with varying fire histories. We used structural equation modeling to investigate how vegetation composition, hydrotopography, and soil properties interplay to shape organic layer C and charcoal C stocks. Pine forests consistently contained larger organic layer C stocks than spruce forests. Charcoal stocks, in contrast, were less consistent across both forest types and study regions as pine forests had higher charcoal C stocks than spruce forests in Trillemarka, while the two forest types contained equal charcoal C stocks in Varaldskogen. Charcoal and soil organic layer C stocks increased with higher fire frequencies (number of fire events over the last 600 years), but not with a shorter time since last fire (TSF). Additionally, vegetation composition, terrain slope, and soil moisture were the most important drivers of the organic layer C stocks, while charcoal C stocks were mainly controlled by the depth of the organic layer. Also, microtopography was of importance for organic layer C and charcoal C, since depressions in the forest floor had more charcoal C than well-drained minor hills.
Authors
Pia Heltoft ThomsenAbstract
No abstract has been registered