Anders Bryn
Research Scientist
Biography
I work as a researcher in a 20 % position in the Department of Land Resource Surveys, Division of Survey and Statistics.
My work is primarily related to vegetation mapping, the project Arealregnskap i utmark (AR18X18), mountain farming and contributions to other departments (applications, articles, dissemination, etc.). I also generally contribute to the development, research and dissemination of methodology for mapping of outfield lands.
My subject areas are:
- vegetation mapping
- distribution modelling
- tree- and forest lines
- ecological climatology
- citizen science
- land use
I have a Master degree in vegetation ecology from the University of Oslo and a PhD in biogeography from the University of Bergen.
Abstract
Purpose Treelines and forest lines (TFLs) have received growing interest in recent decades, due to their potential role as indicators of climate change. However, the understanding of TFL dynamics is challenged by the complex interactions of factors that control TFLs. The review aims to provide an overview over the trends in the elevational dynamics of TFLs in Norway since the beginning of the 20th century, to identify main challenges to explain temporal and spatial patterns in TFL dynamics, and to identify important domains for future research. Method A systematic search was performed using international and Norwegian search engines for peer-reviewed articles, scientific reports, and MA and PhD theses concerning TFL changes. Results Most articles indicate TFL rise, but with high variability. Single factors that have an impact on TFL dynamics are well understood, but knowledge gaps exist with regard to interactions and feedbacks, especially those leading to distributional time lags. Extracting the most relevant factors for TFL changes, especially with regard to climate versus land-use changes, requires more research. Conclusions Existing data on TFL dynamics provide a broad overview of past and current changes, but estimations of reliable TFL changes for Norway as a whole is impossible. The main challenges in future empirically-based predictions of TFLs are to understand causes of time lags, separate effects of contemporary processes, and make progress on the impacts of feedback and interactions. Remapping needs to be continued, but combined with both the establishment of representative TFL monitoring sites and field experiments.
Abstract
The Norwegian area frame survey of land cover and outfield land resources (AR18X18), completed in 2014, provided unbiased statistics of land cover in Norway. The article reports the new statistics, discusses implications of the data set, and provides potential value in terms of research, management, and monitoring. A gridded sampling design for 1081 primary statistical units of 0.9 km2 at 18 km intervals was implemented in the survey. The plots were mapped in situ, aided by aerial photos, and all areas were coded following a vegetation type system. The results provide new insights into the cover and distribution of vegetation and land cover types. The statistic for mire and wetlands, which previously covered 5.8%, has since been corrected to 8.9%. The survey results can be used for environmental and agricultural management, and the data can be stratified for regional analyses. The survey data can also serve as training data for remote sensing and distribution modelling. Finally, the survey data can be used to calibrate vegetation perturbations in climate change research that focuses on atmospheric–vegetation feedback. The survey documented novel land cover statistics and revealed that the national cover of wetlands had previously been underestimated.
Abstract
During recent decades, forests have expanded into new areas throughout the whole of Norway. The processes explained as causing the forest expansion have focused mainly on climate or land use changes. To enable a spatially explicit separation of the effects following these two main drivers behind forest expansion, the authors set out to model the potential for natural forest regeneration following land use abandonment, given the present climatic conditions. The present forest distribution, a number of high-resolution land cover maps, and GIS methods were used to model the potential for natural forest regeneration. Furthermore, the results were tested with independent local models, explanatory variables and predictive modelling. The modelling results show that land use abandonment, in a long-term perspective, has the climatic and edaphic potential to cause natural forest regeneration of 48,800 km2, or 15.9% of mainland Norway. The future natural forest regeneration following land use change or abandonment can now be spatially separated from the effects of climate changes. The different independent model tests support the main findings, but small fractions of the modelled potential natural forest regeneration will probably be caused by other processes than land use abandonment.
Authors
Lawrence R. Kirkendall Kyrre Kausrud Martin Malmstrøm Paul Ragnar Berg Anders Bryn Kjetil Hindar Johanna Järnegren Anders Nielsen Erlend Birkeland Nilsen Brett Kevin Sandercock Eva Bonsak Thorstad Gaute VelleAbstract
The Norwegian Environment Agency has asked VKM to evaluate the risks to biodiversity associated with the import of two species of leeches to Norway, Hirudo medicinalis and H. verbana (so-called medicinal leeches). In addition, they ask that the project group suggest mitigating measures that could reduce any potential risks, should import of the two species be granted.
Authors
Lawrence Richard Kirkendall Kyrre Linné Kausrud Martin Malmstrøm Paul Ragnar Berg Anders Bryn Kjetil Hindar Johanna Järnegren Anders Nielsen Erlend Birkeland Nilsen Brett Kevin Sandercock Eva Bonsak Thorstad Gaute VelleAbstract
Import of leeches for medical use and hobby keeping poses a low risk of negative effects on Norwegian biodiversity. This is the key message in a risk assessment of two species of blood-sucking leeches conducted by VKM for the Norwegian Environment Agency. Background The two species of leeches (Hirudo medicinalis and H. verbana) have in recent years become more commonly used in Western medicine for various procedures where maintaining good blood flow is important. Hirudo medicinalis is considered native to Norway and is found in scattered populations in southern Norway. There is uncertainty about the genetic impact on these populations if imported leeches were to be released into the wild. Hirudo verbana is not registered in Norway but may have been imported as H. medicinalis in the past. Both species are listed under Appendix I, List B of the Norwegian CITES regulations. Methods VKM reviewed scientific literature to uncover potential negative effects in light of the leeches’ ecology under Norwegian conditions. VKM also investigated how the trade in live leeches is conducted, where they originate from, and outlined possible risk-reducing measures. VKM assessed four factors of potential relevance for negative impacts on biodiversity and conducted risk assessments for each: Hybridisation or other negative genetic impacts on local populations Competition with other leech species Parasitism or predation on amphibian populations Transmission of diseases Additionally, VKM assessed the extent of such imports and the likelihood of imported leeches ending up in Norwegian nature. Results VKM concluded that it is moderately likely that H. medicinalis will genetically affect Norwegian populations, but this will have minimal negative effects. Hybridisation between H. verbana and H. medicinalis is considered unlikely and would have little effect if it occurs. ”The leeches already present in Norway mainly originate from leeches imported from Europe in the 1800s. The introduction of new genes from the same areas now will therefore have minimal impact. The risk is therefore low,” says Lawrence Kirkendall, the scientific leader of the work. For parasitism or predation, amphibians are the main species that could theoretically be negatively affected by the leeches. VKM concludes that such negative effects are very unlikely and would have little or minimal impact. This implies low risk. Regarding competition and disease transmission, VKM assesses that these factors have little or minimal effect on biodiversity and are very unlikely. "We assess that the effects on biodiversity in Norway, if imported leeches were to end up in an environment where they thrive, are very small. At the same time, it is very unlikely that leeches used for medical procedures will end up in nature. The overall assessment is therefore that both species are associated with low risk of negative impact on biodiversity," says Kirkendall. The risk assessment is approved by the VKM Panel for Biodiversity.
Authors
Gaute Velle Paul Ragnar Berg Johanna Järnegren Martin Malmstrøm Anders Bryn Kjetil Hindar Lawrence R. Kirkendall Kyrre Linné Kausrud Erlend Birkeland Nilsen Brett Kevin Sandercock Eva Bonsak Thorstad Anders NielsenAbstract
The Norwegian Environment Agency asked VKM to evaluate the risks to biodiversity associated with the importation of eight species of live crabs intended for human consumption. Background Invasive crab species represent a significant threat to biodiversity globally due to their omnivory, adaptability to diverse habitats, high reproductive output, and aggressive behaviour. The Norwegian Environment Agency has raised concerns about the potential ecological risks posed by the import of live crabs to Norway intended for human consumption. This report provides a risk assessment of eight species of crabs that could have negative effects on native biodiversity. The species include Chinese mitten crab (Eriocheir sinensis), Japanese mitten crab (E. japonica), blue crab (Callinectes sapidus), Atlantic rock crab (Cancer irroratus), Asian paddle crab (Charybdis japonica), common moon crab (Matuta victor), African blue swimming crab (Portunus segnis), and Harris mud crab (Rhithropanopeus harrisii). Three of the assessed species were recently confiscated at Norway's border. This suggests a market demand that could increase the frequency of introductions to Norway. Methods VKM established a working group with expertise in invertebrates and risk assessment. The group searched scientific literature for information on the taxonomy, natural history, invasiveness, and ecology for each crab species. If scientific literature was lacking, supplemental google searches allowed for a broader understanding of species with limited research or on the use and transportation of live crabs as food. The assessment utilized the EICAT framework (Environmental Impact Classification for Alien Taxa) to identify potential mechanisms by which each species could harm native biodiversity, should imported specimens become established in Norwegian nature. Key mechanisms include competition, predation, pathogen transmission, and hybridization. The relevant mechanisms were analysed for each species by rating the potential magnitude of impact on biodiversity from minimal to massive. The likelihood of each impact was assessed from very unlikely to very likely. A combination of magnitude of impact and likelihood resulted in final risk levels ranging from low and medium to possibly high and high. Confidence levels for each assessment were also categorized as low, medium, or high based on expert opinion. Results The potential hazards evaluated under the EICAT framework include competition, predation, and transmission of disease for all species, grazing for four species and structural impacts on the ecosystem for three species. The conditions required for crabs imported live for human consumption to reach a natural ecosystem in Norway include a commercial demand for crabs, survival during transport and handling, and the possibility of release or escape. If these conditions for reaching a natural ecosystem are met, the species must then be capable of establishment in the new ecosystem. There are several examples of species imported live for human consumption becoming established in the wild, most likely due to intentional release. The risk assessments indicate varied levels of risk across the five hazards. Competition from E. sinensis or E. japonica was assessed to pose a high risk, while competition from C. sapidus, C. irroratus, M. victor, P. segnis, or R. harrisii was assessed to pose a medium risk. Predation by E. sinensis or E. japonica was assessed to pose a high risk and predation from R. harrisii, C. sapidus, C. irroratus, M. victor, or P. segnis was assessed to pose a medium risk. Transmission of disease from either E. sinensis or E. japonica was assessed to pose a high risk, while there was a possibly high risk of disease transmission from C. irroratus. The diseases of highest concern include the crayfish plague (Aphanomyces astaci) and gaffkaemia (Aerococcus viridans var. homari). Finally, there was a moderate risk of ......