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result(s) for
"Dagmar Egelkraut"
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Close to open—Factors that hinder and promote open science in ecology research and education
by
Boutouli, Grace D.
,
Egelkraut, Dagmar D.
,
Telford, Richard J.
in
Biology and Life Sciences
,
Collaboration
,
Computer and Information Sciences
2022
The Open Science (OS) movement is rapidly gaining traction among policy-makers, research funders, scientific journals and individual scientists. Despite these tendencies, the pace of implementing OS throughout the scientific process and across the scientific community remains slow. Thus, a better understanding of the conditions that affect OS engagement, and in particular, of how practitioners learn, use, conduct and share research openly can guide those seeking to implement OS more broadly. We surveyed participants at an OS workshop hosted by the Living Norway Ecological Data Network in 2020 to learn how they perceived OS and its importance in their research, supervision and teaching. Further, we wanted to know what OS practices they had encountered in their education and what they saw as hindering or helping their engagement with OS. The survey contained scaled-response and open-ended questions, allowing for a mixed-methods approach. We obtained survey responses from 60 out of 128 workshop participants (47%). Responses indicated that usage and sharing of open data and code, as well as open access publication, were the most frequent OS practices. Only a minority of respondents reported having encountered OS in their formal education. A majority also viewed OS as less important in their teaching than in their research and supervisory roles. The respondents’ suggestions for what would facilitate greater OS engagement in the future included knowledge, guidelines, and resources, but also social and structural support. These are aspects that could be strengthened by promoting explicit implementation of OS practices in higher education and by nurturing a more inclusive and equitable OS culture. We argue that incorporating OS in teaching and learning of science can yield substantial benefits to the research community, student learning, and ultimately, to the wider societal objectives of science and higher education.
Journal Article
The role of plant functional groups mediating climate impacts on carbon and biodiversity of alpine grasslands
2022
Plant removal experiments allow assessment of the role of biotic interactions among species or functional groups in community assembly and ecosystem functioning. When replicated along climate gradients, they can assess changes in interactions among species or functional groups with climate. Across twelve sites in the Vestland Climate Grid (VCG) spanning 4 °C in growing season temperature and 2000 mm in mean annual precipitation across boreal and alpine regions of Western Norway, we conducted a fully factorial plant functional group removal experiment (graminoids, forbs, bryophytes). Over six years, we recorded biomass removed, soil microclimate, plant community composition and structure, seedling recruitment, ecosystem carbon fluxes, and reflectance in 384 experimental and control plots. The dataset consists of 5,412 biomass records, 360 species-level biomass records, 1,084,970 soil temperature records, 4,771 soil moisture records, 17,181 plant records covering 206 taxa, 16,656 seedling records, 3,696 ecosystem carbon flux measurements, and 1,244 reflectance measurements. The data can be combined with longer-term climate data and plant population, community, ecosystem, and functional trait data collected within the VCG.Measurement(s)vegetation layer • ecosystem-wide respiration • ecosystem-wide photosynthesis • seedling development stage • temperature of soil • plant functional group biomass • volumetric soil moisture • reflectance spectrumTechnology Type(s)Visual species identification and cover estimation • Licor gas analyzer • Visual species identification and estimation • ibutton temperature logger • Analytical Balance • SM300 soil mositure probe, Delta-T • GreenSeeker/Normalized Difference Vegetation Index measurementsFactor Type(s)temperature • precipitation • Plant functional type compositionSample Characteristic - OrganismEmbryophytaSample Characteristic - Environmentalpine tundra biomeSample Characteristic - LocationVestlandet Region
Journal Article
Hiding in the background: community-level patterns in invertebrate herbivory across the tundra biome
by
Sokolova, Natalia
,
Konieczka, Sophia
,
Speed, James D M
in
Biomass
,
Climate change
,
Climatic conditions
2019
Invertebrate herbivores depend on external temperature for growth and metabolism. Continued warming in tundra ecosystems is proposed to result in increased invertebrate herbivory. However, empirical data about how current levels of invertebrate herbivory vary across the Arctic is limited and generally restricted to a single host plant or a small group of species, so predicting future change remains challenging. We investigated large-scale patterns of invertebrate herbivory across the tundra biome at the community level and explored how these patterns are related to long-term climatic conditions and year-of-sampling weather, habitat characteristics, and aboveground biomass production. Utilizing a standardized protocol, we collected samples from 92 plots nested within 20 tundra sites during summer 2015. We estimated the community-weighted biomass lost based on the total leaf area consumed by invertebrates for the most common plant species within each plot. Overall, invertebrate herbivory was prevalent at low intensities across the tundra, with estimates averaging 0.94% and ranging between 0.02 and 5.69% of plant biomass. Our results suggest that mid-summer temperature influences the intensity of invertebrate herbivory at the community level, consistent with the hypothesis that climate warming should increase plant losses to invertebrates in the tundra. However, most of the observed variation in herbivory was associated with other site level characteristics, indicating that other local ecological factors also play an important role. More details about the local drivers of invertebrate herbivory are necessary to predict the consequences for rapidly changing tundra ecosystems.
Journal Article
Can bryophyte groups increase functional resolution in tundra ecosystems?1
by
Gregory H.R. Henry
,
Christian Rixen
,
Juha M. Alatalo
in
Arctic–Alpine
,
environmental change
,
functional traits
2022
The relative contribution of bryophytes to plant diversity, primary productivity, and ecosystem functioning increases towards colder climates. Bryophytes respond to environmental changes at the species level, but because bryophyte species are relatively difficult to identify, they are often lumped into one functional group. Consequently, bryophyte function remains poorly resolved. Here, we explore how higher resolution of bryophyte functional diversity can be encouraged and implemented in tundra ecological studies. We briefly review previous bryophyte functional classifications and the roles of bryophytes in tundra ecosystems and their susceptibility to environmental change. Based on shoot morphology and colony organization, we then propose twelve easily distinguishable bryophyte functional groups. To illustrate how bryophyte functional groups can help elucidate variation in bryophyte effects and responses, we compiled existing data on water holding capacity, a key bryophyte trait. Although plant functional groups can mask potentially high interspecific and intraspecific variability, we found better separation of bryophyte functional group means compared with previous grouping systems regarding water holding capacity. This suggests that our bryophyte functional groups truly represent variation in the functional roles of bryophytes in tundra ecosystems. Lastly, we provide recommendations to improve the monitoring of bryophyte community changes in tundra study sites.
Journal Article
Long‐term heavy reindeer grazing promotes plant phosphorus limitation in arctic tundra
by
Egelkraut, Dagmar
,
Cherif, Mehdi
,
Giesler, Reiner
in
Antlers
,
Biodiversity and Ecology
,
Cycles
2019
The potential of large mammalian herbivores to shift plant communities between nitrogen (N) and phosphorus (P) limitation has received little attention so far. However, herbivores can influence the cycling of these growth-limiting nutrients, and thereby affect plant nutrient limitation and productivity. Tundra ecosystems are nutrient-poor and commonly grazed by large herbivores like reindeer and may thus be responsive to such changes. Here, we examined the effect of long-term light and heavy reindeer grazing on nutrient limitation of plant growth in a Scandinavian arctic tundra. We are the first to conduct a factorial N and P fertilization experiment across the two grazing regimes in two functionally contrasting vegetation types: heath and meadow. Annual primary productivity (APP) showed contrasting responses to our fertilization treatments under light and heavy grazing. Under light grazing, APP increased in response to N + P additions in both the heath and meadow. Under heavy grazing, APP increased in response to N in the heath, with an additional positive effect of N + P combined, while APP increased in response to P and N + P additions in the meadow. These results clearly show that an increase in the grazing intensity of reindeer facilitated a shift towards more P-limited conditions in Scandinavian arctic tundra, by increasing N cycling without having a corresponding positive effect on P cycling. In the N-poor heath, reindeer increased soil N availability at least partly due to a shift towards more N-rich graminoids, while in the meadow, reindeer decreased soil P availability. The mechanisms behind this decrease remain unclear, but reindeer may simply export more P from the system than N due to their large P demand for the production of their antlers. Synthesis. We conclude that heavy and long-term reindeer grazing promoted a more P-limited tundra, thus experimentally confirming the potential of large mammalian herbivores to influence nutrient limitation of plant growth.
Journal Article
The role of plant–soil feedbacks in stabilizing a reindeer-induced vegetation shift in subarctic tundra
by
Egelkraut, Dagmar
,
De Long, Jonathan R.
,
Olofsson, Johan
in
alternative state
,
Betula nana
,
biomass
2018
Herbivory can drive vegetation into different states of productivity and community composition, and these changes may be stable over time due to historical contingency effects. Interactions with abiotic and biotic soil components can contribute to such long‐term legacies in plant communities through stabilizing positive feedbacks. We studied the role of plant–soil feedbacks in maintaining vegetation changes caused by historical (~1350–1900 AD) reindeer herding in northern Sweden. These historical milking grounds (HMGs) consist of meadow plant communities formed in naturally nutrient‐poor heath or naturally nutrient‐rich shrub‐dominated vegetation and are still clearly visible in the landscape, a century after active use ceased. We selected two phytometer species: the forb Potentilla crantzii as representative of HMG vegetation, and the dwarf shrub Betula nana, as representative of control vegetation. We grew both species under glasshouse conditions on soils derived from replicated HMG and paired control plots, using live soils and sterilized (γ‐radiation)‐inoculated soils, to separate between biotic and abiotic soil effects. A net negative plant–soil feedback for B. nana biomass in its home (i.e., control) soil and a net positive feedback for P. crantzii in its home (i.e., HMG) soil in heath habitat was partly driven by the soil biotic community. However, abiotic differences in mineral nitrogen (N) concentrations between control and HMG soils were a stronger driver of differences in plant growth. Positive feedbacks maintaining a high mineral nutrient availability are thus important, especially in nutrient‐poor habitats. The positive plant responses to higher soil mineral N concentrations, combined with positive biotic plant–soil feedbacks, might shift the competitive balance in favour of typical HMG plant species, thereby contributing to stability of HMG plant communities. Our data indicate that herbivore‐driven changes in the interactions between plants and both biotic and abiotic components of the soil persist over long temporal scales. A plain language summary is available for this article. Plain Language Summary
Journal Article
Multiple Feedbacks Contribute to a Centennial Legacy of Reindeer on Tundra Vegetation
by
Aronsson, Kjell-Åke
,
Egelkraut, Dagmar
,
Stark, Sari
in
alternative stable states
,
Arctic region
,
Biomedical and Life Sciences
2018
Historical contingency is the impact of past events, like the timing and order of species arrival, on community assembly, and can sometimes result in alternative stable states of ecological communities. Large herbivores, wild and domestic, can cause profound changes in the structure and functioning of plant communities and therefore probably influence historical contingency; however, little empirical data on the stability of such shifts or subsequent drivers of stability are available. We studied the centennial legacy of reindeer (Rangifer tarandus) pressure on arctic tundra vegetation by considering historical milking grounds (HMGs): graminoid-and forb-dominated patches amid shrub-dominated tundra, formed by historical Sami reindeer herding practices that ended approximately 100 years ago. Our results show that the core areas of all studied HMGs remained strikingly stable, being hardly invaded by surrounding shrubs. Soil nitrogen concentrations were comparable to heavily grazed areas. However, the HMGs are slowly being reinvaded by vegetative growth of shrubs at the edges, and the rate of ingrowth increased with higher mineral N availability. Furthermore, our data indicate that several biotic feedbacks contribute to the stability of the HMGs: increased nutrient turnover supporting herbaceous vegetation, strong interspecific competition preventing invasion and herbivore damage to invading shrubs. In particular, voles and lemmings appear to be important, selectively damaging shrubs in the HMGs. We concluded that HMGs provide clear evidence for historical contingency of herbivore effects in arctic ecosystems. We showed that several biotic feedbacks can contribute to subsequent vegetation stability, but their relative importance will vary in time and space.
Journal Article
Contrasting vegetation states do not diverge in soil organic matter storage
by
Aronsson, Kjell-Åke
,
Stark, Sari
,
Egelkraut, Dagmar
in
botanical composition
,
Carbon
,
Community composition
2019
Ecosystems where severe disturbance has induced permanent shifts in vegetation and soil processes may represent alternative stable states. To date, little is known on how long-lasting changes in soil processes are following such disturbances, and how the changes in plant and soil processes between the alternative states eventually manifest themselves in soil organic matter (SOM) storage. Here, we analyzed plant density, the shrub : forb ratio, microbial respiration, extracellular enzyme activities and SOM stocks in soils of subarctic tundra and historical milking grounds, where reindeer herding induced a vegetation transition from deciduous shrubs to graminoids several centuries earlier but were abandoned a century ago. This provides the possibility to compare sites with similar topography, but highly contrasting vegetation for centuries. We found that enzymatic activities and N:P stoichiometry differed between control and disturbed sites, confirming that culturally induced vegetation shifts exert lasting impacts on tundra soil processes. Transition zones, where shrubs had encroached into the historical milking grounds during the past 50 yr, indicated that microbial activities for N and P acquisition changed more rapidly along a vegetation shift than those for microbial C acquisition. Although plant and soil processes differed between control and disturbed sites, we found no effect of historical vegetation transition on SOM stock. Across the study sites, soil SOM stocks were correlated with total plant density but not with the shrub : forb ratio. Our finding that SOM stock was insensitive to a centennial difference in plant community composition suggests that, as such, grazing-induced alternative vegetation states might not necessarily differ in SOM sequestration.
Journal Article
Close to open—Factors that hinder and promote open science in ecology research and education
The Open Science (OS) movement is rapidly gaining traction among policy-makers, research funders, scientific journals and individual scientists. Despite these tendencies, the pace of implementing OS throughout the scientific process and across the scientific community remains slow. Thus, a better understanding of the conditions that affect OS engagement, and in particular, of how practitioners learn, use, conduct and share research openly can guide those seeking to implement OS more broadly. We surveyed participants at an OS workshop hosted by the Living Norway Ecological Data Network in 2020 to learn how they perceived OS and its importance in their research, supervision and teaching. Further, we wanted to know what OS practices they had encountered in their education and what they saw as hindering or helping their engagement with OS. The survey contained scaled response and open-ended questions, allowing for a mixed-methods approach. We obtained survey responses from 60 out of 128 workshop participants (47%). Responses indicated that usage and sharing of open data and code, as well as open access publication, were the most frequent OS practices. Only a minority of respondents reported having encountered OS in their formal education. A majority also viewed OS as less important in their teaching than in their research and supervisory roles. The respondents’ suggestions for what would facilitate greater OS engagement in the future included knowledge, guidelines, and resources, but also social and structural support. These are aspects that could be strengthened by promoting explicit implementation of OS practices in higher education and by nurturing a more inclusive and equitable OS culture. We argue that incorporating OS in teaching and learning of science can yield substantial benefits to the research community, student learning, and ultimately, to the wider societal objectives of science and higher education.
Journal Article
Close to open—Factors that hinder and promote open science in ecology research and education
The Open Science (OS) movement is rapidly gaining traction among policy-makers, research funders, scientific journals and individual scientists. Despite these tendencies, the pace of implementing OS throughout the scientific process and across the scientific community remains slow. Thus, a better understanding of the conditions that affect OS engagement, and in particular, of how practitioners learn, use, conduct and share research openly can guide those seeking to implement OS more broadly. We surveyed participants at an OS workshop hosted by the Living Norway Ecological Data Network in 2020 to learn how they perceived OS and its importance in their research, supervision and teaching. Further, we wanted to know what OS practices they had encountered in their education and what they saw as hindering or helping their engagement with OS. The survey contained scaled response and open-ended questions, allowing for a mixed-methods approach. We obtained survey responses from 60 out of 128 workshop participants (47%). Responses indicated that usage and sharing of open data and code, as well as open access publication, were the most frequent OS practices. Only a minority of respondents reported having encountered OS in their formal education. A majority also viewed OS as less important in their teaching than in their research and supervisory roles. The respondents’ suggestions for what would facilitate greater OS engagement in the future included knowledge, guidelines, and resources, but also social and structural support. These are aspects that could be strengthened by promoting explicit implementation of OS practices in higher education and by nurturing a more inclusive and equitable OS culture. We argue that incorporating OS in teaching and learning of science can yield substantial benefits to the research community, student learning, and ultimately, to the wider societal objectives of science and higher education.
Journal Article