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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.

2023

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Abstract

Biodiversity is declining globally in response to multiple human stressors, including climate forcing. Nonetheless, local diversity trends are inconsistent in some taxa, obscuring contributions of local processes to global patterns. Arctic tundra diversity, including plants, fungi, and lichens, declined during a 15-year experiment that combined warming with exclusion of large herbivores known to influence tundra vegetation composition. Tundra diversity declined regardless of experimental treatment, as background growing season temperatures rose with sea ice loss. However, diversity declined slower with large herbivores than without them. This difference was associated with an increase in effective diversity of large herbivores as formerly abundant caribou declined and muskoxen increased. Efforts that promote herbivore diversity, such as rewilding, may help mitigate impacts of warming on tundra diversity.

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Abstract

Peatlands cover only 3–4% of the Earth’s surface, but they store nearly 30% of global soil carbon stock. This significant carbon store is under threat as peatlands continue to be degraded at alarming rates around the world. It has prompted countries worldwide to establish regulations to conserve and reduce emissions from this carbon rich ecosystem. For example, the EU has implemented new rules that mandate sustainable management of peatlands, critical to reaching the goal of carbon neutrality by 2050. However, a lack of information on the extent and condition of peatlands has hindered the development of national policies and restoration efforts. This paper reviews the current state of knowledge on mapping and monitoring peatlands from field sites to the globe and identifies areas where further research is needed. It presents an overview of the different methodologies used to map peatlands in nine countries, which vary in definition of peat soil and peatland, mapping coverage, and mapping detail. Whereas mapping peatlands across the world with only one approach is hardly possible, the paper highlights the need for more consistent approaches within regions having comparable peatland types and climates to inform their protection and urgent restoration. The review further summarises various approaches used for monitoring peatland conditions and functions. These include monitoring at the plot scale for degree of humification and stoichiometric ratio, and proximal sensing such as gamma radiometrics and electromagnetic induction at the field to landscape scale for mapping peat thickness and identifying hotspots for greenhouse gas (GHG) emissions. Remote sensing techniques with passive and active sensors at regional to national scale can help in monitoring subsidence rate, water table, peat moisture, landslides, and GHG emissions. Although the use of water table depth as a proxy for interannual GHG emissions from peatlands has been well established, there is no single remote sensing method or data product yet that has been verified beyond local or regional scales. Broader land-use change and fire monitoring at a global scale may further assist national GHG inventory reporting. Monitoring of peatland conditions to evaluate the success of individual restoration schemes still requires field work to assess local proxies combined with remote sensing and modeling. Long-term monitoring is necessary to draw valid conclusions on revegetation outcomes and associated GHG emissions in rewetted peatlands, as their dynamics are not fully understood at the site level. Monitoring vegetation development and hydrology of restored peatlands is needed as a proxy to assess the return of water and changes in nutrient cycling and biodiversity.

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Abstract

Questions Field-based ecosystem mapping is prone to observer bias, typically resulting in a mismatch between maps made by different mappers, that is, inconsistency. Experimental studies testing the influence of site, mapping scale, and differences in experience level on inconsistency in field-based ecosystem mapping are lacking. Here, we study how inconsistencies in field-based ecosystem maps depend on these factors. Location Iškoras and Guollemuorsuolu, northeastern Norway, and Landsvik and Lygra, western Norway. Methods In a balanced experiment, four sites were field-mapped wall-to-wall to scales 1:5000 and 1:20,000 by 12 mappers, representing three experience levels. Thematic inconsistency was calculated by overlay analysis of map pairs from the same site, mapped to the same scale. We tested for significant differences between sites, scales, and experience-level groups. Principal components analysis was used in an analysis of additional map inconsistencies and their relationships with site, scale and differences in experience level and time consumption were analysed with redundancy analysis. Results On average, thematic inconsistency was 51%. The most important predictor for thematic inconsistency, and for all map inconsistencies, was site. Scale and its interaction with site predicted map inconsistencies, but only the latter were important for thematic inconsistency. The only experience-level group that differed significantly from the mean thematic inconsistency was that of the most experienced mappers, with nine percentage points. Experience had no significant effect on map inconsistency as a whole. Conclusion Thematic inconsistency was high for all but the dominant thematic units, with potentially adverse consequences for mapping ecosystems that are fragmented or have low coverage. Interactions between site and mapping system properties are considered the main reasons why no relationships between scale and thematic inconsistency were observed. More controlled experiments are needed to quantify the effect of other factors on inconsistency in field-based mapping.

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Abstract

Landscape ecology is repeatedly described as an applied science that can help reduce the negative effects of land-use and land-use changes on biodiversity. However, the extent to which landscape ecology is in fact contributing to planning and design processes is questioned. The aim of this paper is to investigate if and how landscape ecology can be integrated in a planning and design process, and to uncover possible problems that, e.g., landscape architects and planners, may face in such processes. Our conclusion, based on a case study from Asker municipality, Norway, is that such a landscape ecological approach has a lot to offer. However, it is difficult to exploit the potential fully for different reasons, e.g., biodiversity information tends to be specialized, and not easily used by planners and designers, and landscape ecological principles need an adaptation process to be applicable in a real-world situation. We conclude that for the situation to improve, landscape ecologists need to ease this process. In addition, we recommend collaboration across disciplinary boundaries, preferably with a common design concept as a foundation.

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Abstract

Renting agricultural land is a common practice in many countries. The possibility to rent land provides farmers with increased flexibility in terms of production volume. Land renting may have various effects on farmland management; however, results from studies analysing these are ambivalent. Farmland in the best possible state is a prerequisite for following up ambitions of feeding a growing population through a sustainable agriculture. Decisions regarding investments on farmland are key. The aim of this study is to increase the understanding of which factors are the most important ones for farmers’ decisions about investments on land they rent. We carried out a questionnaire survey followed by a multiple linear regression considering 34 variables. Although variables included in our model come out as significant in explaining investments, a large part of the variation is left unexplained (R2 = 0.22). Our interpretation of this result is that making investments is a complex decision. Non-economic factors impacting on farmers’ investment decisions such as trust or norms may contribute to the unexplained variation, but may only have been captured partly by our variables. Moreover, decisions regarding investments may not only vary among farmers but also among investments made by an individual farmer. The complex nature of the decisions on how to treat rented land makes it challenging for policymakers to develop measures targeted at farmers renting land. However, the finding that farmers are driving longer distances to rented land than they find acceptable deserves political attention. One potential policy implication may be strengthened incentives for land re-allotment. Re-allotment may address increasing distances and potential consequences such as reduced productivity and increased land abandonment. However, the sustainability of a re-allotment process needs to be considered carefully in terms of economic viability, ecological soundness and social responsibility.