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In the high Arctic, plant community species composition generally responds slowly to climate warming, whereas less is known about the community functional trait responses and consequences for ecosystem functioning. Slow species turnover and large distribution ranges of many Arctic plant species suggest a significant role of intraspecific trait variability in functional responses to climate change. Here, we compare taxonomic and functional community compositional responses to a long-term (17 years) warming experiment in Svalbard, replicated across three major high Arctic habitats shaped by topography and contrasting snow regimes. We observed taxonomic compositional changes in all plant communities over time. Still, responses to experimental warming were minor and most pronounced in the drier habitats with relatively early snowmelt timing and long growing seasons (Cassiope and Dryas heaths). The habitats were clearly separated in functional trait space, defined by twelve size- and leaf economics-related traits, primarily due to interspecific trait variation. Functional traits also responded to experimental warming, most prominently in the Dryas heath and mostly due to intraspecific trait variation. Leaf area and leaf mass increased, and leaf δ15N decreased in response to the warming treatment. Intraspecific trait variability ranged between 30% and 71% of the total trait variation, reflecting functional resilience of those communities, dominated by long-lived plants, due to either phenotypic plasticity or genotypic variation that most likely underlies the observed resistance of high Arctic vegetation to climate warming. We further explored the consequences of trait variability for ecosystem functioning by measuring peak season CO2 fluxes. Together, environmental, taxonomic, and functional trait variables explained a large proportion of the variation in net ecosystem exchange (NEE), which increased when intraspecific trait variation was accounted for. In contrast, even though ecosystem respiration and gross ecosystem production both increased in response to warming across habitats, they were mainly driven by the direct kinetic impacts of temperature on plant physiology and biochemical processes. Our study shows that long-term experimental warming has a modest but significant effect on plant community functional trait composition and suggests that intraspecific trait variability is a key feature underlying high Arctic ecosystem resistance to climate warming.

SummaryEcological theory posits that temporal stability patterns in plant populations are associated with differences in species’ ecological strategies. However, empirical evidence is lacking about which traits, or trade-offs, underlie species stability, specially across different ecosystems.To address this, we compiled a global collection of long-term permanent vegetation records (>7000 plots from 78 datasets) from a wide range of habitats and combined this with existing trait databases. We tested whether the observed inter-annual variability in species abundance (coefficient of variation) was related to multiple individual traits and multivariate axes of trait variations (PCoA axes).We found that species with greater leaf dry matter content and seed mass were consistently more stable over time (lower variability in species abundance) although other leaf traits played a significant role as well, albeit weaker. Using multivariate axes did not improve predictions by specific traits.Our results confirm existing theory, providing compelling empirical evidence on the importance of specific traits, which point at ecological trade-offs in different resource use and dispersal strategies, on the stability of plant populations worldwide.

A fundamental assumption in trait-based ecology is that relationships between traits and environmental conditions are globally consistent. We use field-quantified microclimate and soil data to explore if trait–environment relationships are generalizable across plant communities and spatial scales. We collected data from 6,720 plots and 217 species across four distinct tundra regions from both hemispheres. We combined these data with over 76,000 database trait records to relate local plant community trait composition to broad gradients of key environmental drivers: soil moisture, soil temperature, soil pH and potential solar radiation. Results revealed strong, consistent trait–environment relationships across Arctic and Antarctic regions. This indicates that the detected relationships are transferable between tundra plant communities also when fine-scale environmental heterogeneity is accounted for, and that variation in local conditions heavily influences both structural and leaf economic traits. Our results strengthen the biological and mechanistic basis for climate change impact predictions of vulnerable high-latitude ecosystems. acceptedVersion

Scaling approaches in ecology assume that traits are the main attributes by which organisms influence ecosystem functioning. However, several recent empirical papers have found only weak links between traits and ecosystem functioning, questioning the usefulness of trait-based ecology (TBE). We argue that these studies often suffer from one or more widespread misconceptions. Specifically, these studies often (i) conflict with the conceptual foundations of TBE, (ii) lack theory- or hypothesis-driven selection and use of traits, (iii) tend to ignore intraspecific variation, and (iv) use experimental or study designs that are not well suited to make strong tests of TBE assumptions. Addressing these aspects could significantly improve our ability to scale from traits to ecosystem functioning.

Aim\ud \ud Climate and land use are key determinants of biodiversity, with past and ongoing changes posing serious threats to global ecosystems. Unlike most other organism groups, plant species can possess dormant life‐history stages such as soil seed banks, which may help plant communities to resist or at least postpone the detrimental impact of global changes. This study investigates the potential for soil seed banks to achieve this.\ud \ud \ud \ud Location\ud \ud Europe.\ud \ud \ud \ud Time period\ud \ud 1978–2014.\ud \ud \ud \ud Major taxa studied\ud \ud Flowering plants.\ud \ud \ud \ud Methods\ud \ud Using a space‐for‐time/warming approach, we study plant species richness and composition in the herb layer and the soil seed bank in 2,796 community plots from 54 datasets in managed grasslands, forests and intermediate, successional habitats across a climate gradient.\ud \ud \ud \ud Results\ud \ud Soil seed banks held more species than the herb layer, being compositionally similar across habitats. Species richness was lower in forests and successional habitats compared to grasslands, with annual temperature range more important than mean annual temperature for determining richness. Climate and land‐use effects were generally less pronounced when plant community richness included seed bank species richness, while there was no clear effect of land use and climate on compositional similarity between the seed bank and the herb layer.\ud \ud \ud \ud Main conclusions\ud \ud High seed bank diversity and compositional similarity between the herb layer and seed bank plant communities may provide a potentially important functional buffer against the impact of ongoing environmental changes on plant communities. This capacity could, however, be threatened by climate warming. Dormant life‐history stages can therefore be important sources of diversity in changing environments, potentially underpinning already observed time‐lags in plant community responses to global change. However, as soil seed banks themselves appear, albeit less, vulnerable to the same changes, their potential to buffer change can only be temporary, and major community shifts may still be expected.

Plants are responding to climate change by shifting their ranges to higher elevations. These range shifts are not happening at the same rate for all species, for example, subalpine species are generally moving faster upslope than alpine species, but with large variation within groups. This asymmetry in migration rates will result in novel communities and interactions between plant species that have not previously co-occurred. While seed dispersal is obviously critical for species’ range shifts, seedling emergence and survival are also major bottlenecks for successful colonization in new areas. As seedlings generally constitute the most vulnerable stages in the life-history of plants, variation in seedling establishment success can potentially be important determinants of species’ range shift rates. Previous studies have found that warming per se tends to increase seedling establishment in alpine climates, but it also increases plant productivity and thus competition for nutrients and light from the resident vegetation, which acts limiting on seedling establishment. This study will attempt to disentangle the relative importance of these abiotic and biotic factors on sub-alpine species’ seedling emergence and survival in alpine habitats, to help further understanding and prediction of future lowland plant colonization in alpine habitats. We will also explore if species’ life strategies impact their ability to colonize new locations, predicting that species with resource acquisitive traits will emerge earlier and faster than resource conservative species. To address these questions, we will perform a seed transplant experiment where we assess seedling emergence and establishment in the alpine. Seeds will be sown in plots with and without experimental warming, crossed with manipulation of biotic interactions, and using seeds from both resource conservative and resource acquisitive subalpine species. In addition, we will explore if the observed responses are general or context-dependent by replicating this experiment along a regional bioclimatic precipitation gradient.

Herbivores shape vegetation by suppressing certain plant species while benefitting others. By thus modifying plant species functional composition, herbivores affect carbon cycling, albedo, vegetation structure and species' interactions. These effects have been suggested to be able to counteract the effects of increasing temperatures on vegetation in alpine environments. Managing the dominant large ungulates in these ecosystems could thus provide a tool to mitigate climate change effects. However, it is possible that legacy effects of past grazing will dampen ungulate impacts on vegetation. We shed a light on this topic by investigating the short- and long-term effects of varying sheep densities on the plant trait composition in the Norwegian alpine tundra with centuries-long of intensive grazing history. In the first part of our study, we quantified the effects of sheep on the plant community functional trait composition at different elevations and under moderate and low productivity in. We combined data from two long-term (14 and 19 yr) sheep fence experiments and showed that differences in sheep densities did not affect plant trait composition, irrespective of productivity. However, in the second part of our study, we showed that the plant trait composition in mainland (that has been grazed for centuries) differed from vegetation on islands which have been herbivore-free. Taken together, these results suggest that sheep have an effect on the alpine plant communities on historical time scales covering centuries, but that the resulting sheep grazing resistant/tolerant communities may not respond to shorter-term (14 and 19 yr) changes in sheep densities, that is, at temporal scales relevant for ecosystem management. Furthermore, we showed that the plant trait composition at the site with low productivity had gone through a temporal trait change independent of sheep treatment, potentially due to increased temperatures and precipitation, suggesting that sheep may not be able to counteract climatic impacts in the areas with centuries-long grazing history. publishedVersion

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.

Open Science (OS) comprises a variety of practices and principles that are broadly intended to improve the quality and transparency of research, and the concept is gaining traction. Since OS has multiple facets and still lacks a unifying definition, it may be interpreted quite differently among practitioners. Moreover, successfully implementing OS broadly throughout science requires a better understanding of the conditions that facilitate or hinder OS engagement, and in particular, how practitioners learn OS in the first place. We addressed these issues by surveying OS practitioners that attended a workshop hosted by the Living Norway Ecological Data Network in 2020. The survey contained scaled-response and open-ended questions, allowing for a mixed-methods approach. Out of 128 registered participants we obtained survey responses from 60 individuals. Responses indicated usage and sharing of data and code, as well as open access publications, as the OS aspects most frequently engaged with. Men and those affiliated with academic institutions reported more frequent engagement with OS than women and those with other affiliations. When it came to learning OS practices, only a minority of respondents reported having encountered OS in their own formal education. Consistent with this, a majority of respondents viewed OS as less important in their teaching than in their research and supervision. Even so, many of the respondents’ suggestions for what would help or hinder individual OS engagement included more knowledge, guidelines, resource availability and social and structural support; indicating that formal instruction can facilitate individual OS engagement. We suggest that the time is ripe to incorporate OS in teaching and learning, as this can yield substantial benefits to OS practitioners, student learning, and ultimately, the objectives advanced by the OS movement.

Estimating the distribution of phenotypes in populations and communities is central to many questions in ecology and evolutionary biology. These distributions can be characterized by their moments: the mean, variance, skewness, and kurtosis. Typically, these moments are calculated using a community-weighted approach (e.g. community-weighted mean) which ignores intraspecific variation. As an alternative, bootstrapping approaches can incorporate intraspecific variation to improve estimates, and also quantify uncertainty in the estimate. Here, we compare the performance of different approaches for estimating the moments of trait distributions across a variety of sampling scenarios, taxa, and datasets. We introduce the traitstrap R package to facilitate inferences of trait distributions via bootstrapping. Our results suggest that randomly sampling ~9 individuals per sampling unit and species, focusing on covering all species in the community, and analysing the data using nonparametric bootstrapping generally enables reliable inference on trait distributions, including the central moments, of communities.

AimsKnowledge of genetic structure of natural populations and its determinants may provide key insights into the ability of species to adapt to novel environments. In many genetic studies, the effects of climate could not be disentangled from the effects of geographic proximity. We aimed to understand the effects of temperature and moisture on genetic diversity of populations and separate these effects from the effects of geographic distance. We also wanted to explore the patterns of distribution of genetic diversity in the system and assess the degree of clonality within the populations. We also checked for possible genome size variation in the system.MethodsWe studied genetic variation within and among 12 populations of the dominant grass Festuca rubra distributed across a unique regional-scale climatic grid in western Norway, Europe and explored the importance of temperature, precipitation and geographic distance for the observed patterns. We also explored the distribution of genetic diversity within and among populations, identified population differentiation and estimated degree of clonality. The analyses used microsatellites as the genetic marker. The analyses were supplemented by flow cytometry of all the material.Important FindingsAll the material corresponds to hexaploid cytotype, indicating that ploidy variation does not play any role in the system. The results indicate that temperature and precipitation were better predictors of genetic relatedness of the populations than geographic distance, suggesting that temperature and precipitation may be important determinants of population differentiation. In addition, precipitation, alone and in interaction with temperature, strongly affected population genotypic diversity suggesting increased clonality towards the coldest and especially the coldest wettest climates. At the same time, individuals from the coldest and wettest climates also had the highest individual genetic diversity, suggesting that only the most heterozygous individuals survive under these harsh climates. Most of the genetic variation was distributed within populations, suggesting that most populations have sufficient genetic diversity to adapt to novel climatic conditions. The alpine populations, i.e. populations which are likely the most endangered by climate change, however, lack this potential due to the high levels of clonality as detected in our study.

Plant species of semi-natural grasslands are threatened by several simultaneous global change drivers, most notably land-use and climate change. In this study, we explore spatiotemporal variation and changes in deterministic (λ) and stochastic population growth rates (λs), and the underlying vital rates of eight populations of Arnica montana at the species’ north-western range margin in Norway. We assess to what extent variation in the demographic rates could be attributed to environmental correlates of the key global change drivers likely to operate at the range edge, including population size, surrogates of habitat quality, temperature and precipitation. We found no relationship between λ and population size or habitat quality, but λ declined in response to both increasing precipitation and increasing temperature. Life-table response experiments revealed that the temporal variability was driven by survival and clonality, whereas the spatial variation was driven by clonality. Our results suggest that A. montana has a threshold response to increasing precipitation, likely due to adaptations to local climatic conditions. Growth and flowering were both negatively affected by increasing temperature, but these effects had a low influence on the spatiotemporal variability in λ. In contrast, the stochastic growth rate was negatively influenced by climate change, indicating an increased extinction risk for marginal populations, possibly leading to range contraction of A. montana as climate change proceeds. Altogether, our study illustrates how the fates of peripheral populations, which are critically important in species range dynamics, may be affected by both deterministic and stochastic effects of multiple coinciding global change drivers.

Perceived novelty in mobile applications is an inevitable aspect of today's technologies. Studies suggest that this perceived novelty effect increases motivation but wanes once the user becomes accustomed to the product. Using a Self-Determination Theory approach, the present study investigates how different tools relate to students' motivation, basic psychological needs, and achievement, over and above the effect of perceived novelty. The results from a randomized controlled experiment show that a mobile-learning tool and a digital version of a textbook are perceived as more novel than a traditional textbook. However, only the mobile-learning tool enhances the students' basic psychological needs. Additionally, using path-analysis, we find that the mobile-learning tool, need-satisfaction within the mobile-learning tool, and autonomous motivation account for achievement and internalization, over and above the effect of novelty. We argue that this finding is due to the inherent need-supportive elements within the mobile-learning tool that satisfy the basic psychological needs.

The coastal heathlands of North-west Europe are valuable cultural landscapes, created and maintained over millennia by a land-use regime involving burning and grazing. These heathlands are now critically threatened throughout their range by land-use change and, increasingly, climatic changes. The climatic change impacts are complex, as the coastal heathland regions are experiencing increased temperature and precipitation, but also increased frequency and severity of extreme events, such as drought. Previous studies reveal that established heathland vegetation, including Calluna, are vulnerable to drought, but also that these vulnerabilities vary throughout the range, and with successional stage after fire. Recruitment from seed is an important regeneration strategy for Calluna heathland vegetation after burning, and our study is the first to assess how the seed germination and early seedling growth of Calluna respond to drought. We will do this in a lab germination experiment, where we will expose Calluna seeds to five different drought treatments, from -0.25 MPa to -1.7 MPa, and measure germination, and record germination percentage, germination rates, and seedling growth, below-ground allocation, and functional traits (Specific Leaf Area, Specific Root Length). To allow assessment of variation in drought responses due to geographic origin, successional stage, and the maternal plants’ drought exposure, we will conduct this experiment on seeds from 540 Calluna plants sampled from across three drought treatments (control, 50%, and 90% coverage), in three successional stages after fire (pioneer, building, mature), in two regions (60N, 65N), using a factorial design.

Filing gaps in our understanding of species' abilities to adapt to novel climates is a key challenge for predicting future range shifts and biodiversity loss. Key knowledge gaps are related to the potential for evolutionary rescue in response to climate, especially in long-lived clonally reproducing species. We illustrate a novel approach to assess the potential for evolutionary rescue using a combination of reciprocal transplant experiment in the field to assess performance under a changing climate and independent growth chamber assays to assess growth- and physiology-related plant trait maxima and plasticities of the same clones. We use a clonal grass, Festuca rubra, as a model species. We propagated individual clones and used them in a transplant experiment across broad-scale temperature and precipitation gradients, simulating the projected direction of climate change in the region. Independent information on trait maxima and plasticities of the same clones was obtained by cultivating them in four growth chambers representing climate extremes. Plant survival was affected by interaction between plant traits and climate change, with both trait plasticities and maxima being important for adaptation to novel climates. Key traits include plasticity in extravaginal ramets, aboveground biomass, and osmotic potential. The direction of selection in response to a given climatic change detected in this study mostly contradicted the natural trait clines indicating that short-term selection pressure as identified here does not match long-term selection outcomes. Long-lived clonal species exposed to different climatic changes are subjected to consistent selection pressures on key traits, a necessary condition for adaptation to novel conditions. This points to evolutionary rescue as an important mechanism for dealing with climate change in these species. Our experimental approach may be applied also in other model systems broadening our understanding of evolutionary rescue. Such knowledge cannot be easily deduced from observing the existing field clines.

Premise Despite the existence of many studies on the responses of plant species to climate change, there is a knowledge gap on how specific climatic factors and their interactions regulate seed germination in alpine species. This understanding is complicated by the interplay between responses of seeds to the environment experienced during germination, the environment experienced by the maternal plant during seed development and genetic adaptations of the maternal plant to its environment of origin. Methods The study species (Anthoxanthum alpinum, A. odoratum) originated from localities with factorial combinations of temperature and precipitation. Seed germination was tested in conditions simulating the extreme ends of the current field conditions and a climate change scenario. We compared the performance of field-collected seeds with that of garden-collected seeds. Results A change to warmer and wetter conditions resulted in the highest germination of A. alpinum, while A. odoratum germinated the most in colder temperature and with home moisture. The maternal environment did have an impact on plant performance of the study species. Field-collected seeds of A. alpinum tolerated warmer conditions better than those from the experimental garden. Conclusions The results demonstrate how knowledge of responses to climate change can increase our ability to understand and predict the fate of alpine species. Studies that aim to understand the germination requirements of seeds under future climates should use experimental designs allowing the separation of genetic differentiation, plasticity and maternal effects and their interactions, since all these mechanisms play an important role in driving species' germination patterns.

Climate change is a world‐wide threat to biodiversity and ecosystem structure, functioning and services. To understand the underlying drivers and mechanisms, and to predict the consequences for nature and people, we urgently need better understanding of the direction and magnitude of climate change impacts across the soil–plant–atmosphere continuum. An increasing number of climate change studies are creating new opportunities for meaningful and high‐quality generalizations and improved process understanding. However, significant challenges exist related to data availability and/or compatibility across studies, compromising opportunities for data re‐use, synthesis and upscaling. Many of these challenges relate to a lack of an established ‘best practice’ for measuring key impacts and responses. This restrains our current understanding of complex processes and mechanisms in terrestrial ecosystems related to climate change.To overcome these challenges, we collected best‐practice methods emerging from major ecological research networks and experiments, as synthesized by 115 experts from across a wide range of scientific disciplines. Our handbook contains guidance on the selection of response variables for different purposes, protocols for standardized measurements of 66 such response variables and advice on data management. Specifically, we recommend a minimum subset of variables that should be collected in all climate change studies to allow data re‐use and synthesis, and give guidance on additional variables critical for different types of synthesis and upscaling. The protocols are also available online on the ClimEx handbook webpage (https://climexhandbook.w.uib.no/) and we encourage scientists from the climate change research community to get involved, give us feedback and make suggestions for updates to specific protocols. We hope that this is a way to amend the protocols and extend the shelf life of the ClimEx Handbook.The goal of this community effort is to facilitate awareness of the importance and broader application of standardized methods to promote data re‐use, availability, compatibility and transparency. We envision improved research practices that will increase returns on investments in individual research projects, facilitate second‐order research outputs and create opportunities for collaboration across scientific communities. Ultimately, this should significantly improve the quality and impact of the science, which is required to fulfil society's needs in a changing world.

From the lens of Self‐Determination Theory, this study investigated the effects of a mobile application tool for identifying species on biology students' achievement and well‐being. It was hypothesized that the mobile application, compared to a textbook, would enhance feelings of competence and autonomy and, in turn, intrinsic motivation, positive affect and achievement, because the mobile application's built‐in functions provide students with choice and volition, informational feedback, and optimal challenges. Fifty‐eight second‐year students were randomly assigned to use either the mobile application or a textbook for a learning task. Well‐being was assessed before and after the learning task, and intrinsic motivation, perceived competence, perceived autonomy and achievement were assessed after the task. Results indicated that the mobile application, relative to the textbook, produced higher levels of students' perceived competence, perceived autonomy and intrinsic motivation. Further, the mobile application had indirect effects on positive affect through autonomy, competence and intrinsic motivation, and on achievement through competence. [ABSTRACT FROM AUTHOR]

International audience; In climate change ecology, simplistic research approaches may yield unrealistically simplistic answers to often more complicated problems. In particular, the complexity of vegetation responses to global climate change begs a better understanding of the impacts of concomitant changes in several climatic drivers, how these impacts vary across different climatic contexts, and of the demographic processes underlying population changes. Using a replicated, factorial, whole‐community transplant experiment, we investigated regional variation in demographic responses of plant populations to increased temperature and/or precipitation. Across four perennial forb species and 12 sites, we found strong responses to both temperature and precipitation change. Changes in population growth rates were mainly due to changes in survival and clonality. In three of the four study species, the combined increase in temperature and precipitation reflected nonadditive, antagonistic interactions of the single climatic changes for population growth rate and survival, while the interactions were additive and synergistic for clonality. This disparity affects the persistence of genotypes, but also suggests that the mechanisms behind the responses of the vital rates differ. In addition, survival effects varied systematically with climatic context, with wetter and warmer + wetter transplants showing less positive or more negative responses at warmer sites. The detailed demographic approach yields important mechanistic insights into how concomitant changes in temperature and precipitation affect plants, which makes our results generalizable beyond the four study species. Our comprehensive study design illustrates the power of replicated field experiments in disentangling the complex relationships and patterns that govern climate change impacts across real‐world species and landscapes.

Changes in both temperature and precipitation will affect snowmelt time at high elevation, thereby influencing plant reproduction and growth. Species can respond to changed climate with phenotypic plasticity or genetic adaptation, and these responses might vary at different levels of advanced and delayed snowmelt time. Here we mimicked future climate change projections for western Norway by transplanting individuals of Ranunculus acris towards warmer, wetter and warmer & wetter climates. And we replicated the experiment along regional-scale temperature and precipitation gradients. This setup resulted in both advanced (warmer and warmer & wetter transplants) and delayed (wetter transplants) snowmelt in the experimental sites. We recorded phenological development and growth over one growing season. The reproductive phenology of the transplanted R. acris individuals was affected by both phenotypic plasticity and genetic differences between populations of different origins, while growth showed only plastic responses. Plants expressed high plasticity to both advanced and delayed snowmelt time by acceleration of the onset of buds, flowers and fruits. Only the plants from wet and high-elevation sites showed a small response to advanced SMT. The late snowmelt time these populations experience could potentially cause high selection pressure leading to more constrains in plasticity. When grown under common conditions, plants from late snowmelt sites responded with earlier onset of phenological development, suggesting that the timing of snowmelt exerts strong selection on reproduction. To project species fates under future climate we need to consider the interplay between genetic adaptation and plastic responses under different climate contexts, especially towards the species range limits.

UV-B absorbing compounds such as para-coumaric acid are a major constituent of the sporopollenin-based exines of pollen grains. Recent research indicates that these compounds are found in higher concentrations in the pollen of plants exposed to higher levels of UV-B radiation and studies have proposed that variations of para-coumaric acid within fossil pollen could act as a proxy for changes in the amount of UV-B reaching the Earth's surface. However, the low analytical precision in the established method using Thermally Assisted Hydrolysis and Methylation with pyrolysis Gas-Chromatography Mass-Spectrometry (THM–GC/MS) means that quantification of UV-B absorbing compounds within sporopollenin remains a major challenge. Here, we test a variety of normalisation procedures combined with THM–GC/MS to find a method that can provide improved analytical precision in the quantification of UV-B absorbing compounds for Pinus sylvestris L. pollen. Normalisation of UV-B absorbing compounds against non-UV-B absorbing compounds found within sporopollenin was compared to external and internal standard-based approaches. Of the different methods tested, vanillic acid (4-hydroxy-3-methoxybenzoic acid) used as an internal standard provided the best potential for improved performance, with analytical precision improving by approximately 43% when the next-best normalisation procedures were used. Using this method, we estimate the abundance of para-coumaric acid to be 0.34 ± 0.02 ng grain− 1 (95% confidence intervals, n = 20) from a sample collected from a P. sylvestris individual from Catalunya, Spain. The findings from this study provide advantages to previous THM–GC/MS procedures proposed for quantification of para-coumaric acid in pollen grains in terms of improved analytical precision and increased robustness. This will result in improved consistency for batches of samples analysed over long time periods and will enable comparisons between sample sets run in different laboratories.

Successional dynamics in plant community assembly may result from both deterministic and stochastic ecological processes. The relative importance of different ecological processes is expected to vary over the successional sequence, between different plant functional groups, and with the disturbance levels and land-use management regimes of the successional systems. We evaluate the relative importance of stochastic and deterministic processes in bryophyte and vascular plant community assembly after fire in grazed and ungrazed anthropogenic coastal heathlands in Northern Europe. A replicated series of post-fire successions (n = 12) were initiated under grazed and ungrazed conditions, and vegetation data were recorded in permanent plots over 13 years. We used redundancy analysis (RDA) to test for deterministic successional patterns in species composition repeated across the replicate successional series and analyses of co-occurrence to evaluate to what extent species respond synchronously along the successional gradient. Change in species co-occurrences over succession indicates stochastic successional dynamics at the species level (i.e., species equivalence), whereas constancy in co-occurrence indicates deterministic dynamics (successional niche differentiation). The RDA shows high and deterministic vascular plant community compositional change, especially early in succession. Co-occurrence analyses indicate stochastic species-level dynamics the first two years, which then give way to more deterministic replacements. Grazed and ungrazed successions are similar, but the early stage stochasticity is higher in ungrazed areas. Bryophyte communities in ungrazed successions resemble vascular plant communities. In contrast, bryophytes in grazed successions showed consistently high stochasticity and low determinism in both community composition and species co-occurrence. In conclusion, stochastic and individualistic species responses early in succession give way to more niche-driven dynamics in later successional stages. Grazing reduces predictability in both successional trends and species-level dynamics, especially in plant functional groups that are not well adapted to disturbance. bryophytes; burning; Calluna vulgaris; coexistence; conservation management; determinism; disturbance; grazing; heathland; randomization test; stochasticity; vascular plants. Changing contributions of stochastic and deterministic processes in community assembly over a successional gradient

I den offentlege debatten om hogare utdanning er undervisarane pafallande fraverande. Dei sterkaste stemmene tilhoyrar politikarane, studentane, institusjonsleiarane og pedagogane. Nar undervisarane melder seg pa er det oftast i ein klagesong over hogt arbeidspress, krevjande studentar og mangel pa tid og ressursar til forsking. Kvifor oppfattar brorparten av undervisarar i hogare utdanning undervising som ei byrde og forsking som eit privilegium? Ein viktig skilnad ligg i kulturen, det kollegiale fellesskapet, som er sterkt og levande i forskinga, men naermast fraverande i undervisinga. Dette blir stadfesta i ei nasjonal undersoking av studentar, undervisingsstab og arbeidsgjevarar innan biologiske fag. Eit av hovudmala til Senter for framifra utdanning i biologi (bioCEED) er a bygge ein kollegial og forskande laerarkultur (Scholarship of Teaching and Learning – SoTL). Vi meiner at nokkelen til a utvikle ein SoTL kultur er a bringe det beste fra forskarkulturen inn i undervisingskulturen. A dokumentere, skildre og forankre undervisninga i pedagogisk teori og a dele erfaringar i laerarkollegiet, er ei ny oppleving for mange undervisarar – men likevel kjent for dei fleste i deira forskarrolle. Her viser vi korleis ein systematisk institusjonell innsats for a bygge ein forskande og kollegial laerarkultur, inspirert av forskarkulturen, kan hjelpe ei gruppe undervisarar a finne eit felles sprak og si eiga stemma i diskusjonen om laering og undervising. Ein kollegial og forskande laerarkultur endrar innhaldet og hevar nivaet pa dei undervisingsfaglege diskusjonane, og aukar og engasjement, og deltaking i debatten om laering og undervising bade lokalt og offentle

Education within higher education is often divided into discipline-oriented and professional programs. Professional programs prepare students for a specific profession and include relevant theoretical- and practical knowledge. Discipline-oriented programs emphasize theoretical knowledge and research within a specific discipline or field. Except for a career within research and higher education, discipline-oriented programs provide less obvious links to future careers. The transition from student life to working life may therefore be challenging. In this paper, we present and discuss the development and implementation of a work placement course as part of the disciplinary programs in biology at the University of Bergen. The course was developed to provide students with practical- and work- related skills and competences, inform about future careers and to foster motivation and learning. We have revised the course according to feedback from students, workplace hosts and our experience during the six semesters the course has been running. The work placement course is at the bachelor (BSc) level and consists of two main components; the work placement itself and the student’s own reporting of placement outcomes. For the placement, the students work 140 hours at a workplace as a biologist. The reporting consists of four open blog-posts, one written reflective essay and a final oral presentation. The course teachers also meet with the students and convey information on the roles of biology and biologists in today’s society through a Facebook group. Feedback from the students, hosts and course teachers point to a range of benefits from work practice courses in discipline- oriented study programs. Based on our experience, we provide guidance for developing such courses as part of discipline-oriented curricula.

Remnant forest fragments provide an opportunity for conservation in fragmented landscapes but some patches are more useful than others. Forest fragments around Budongo Forest Reserve, an Important Bird Area in western Uganda, were surveyed to explore the effects of different aspects of habitat fragmentation on bird guild composition. We recorded 1 128 individuals of 75 bird species over 7 056 net hours. The greatest number of birds and species were recorded in the forest fragments that were large, near to the continuous forest and surrounded by subsistence farmland. However, rarefied species richness was not affected by distance, size or matrix type; instead, forest specialist species were replaced by generalists and visitors with increasing fragmentation. The proportion of forest specialists and of terrestrial insectivores decreased with distance from the main forest, canopy openness and matrix intensity but not with fragment area. The findings show that bird assemblages vary in their response to habitat fragmentation but within guilds the response to fragmentation can be consistent, and can make ecological sense. Forest bird conservation can therefore benefit from information on species ecology when deciding which bird species and which parts of the landscape are to be prioritised for conservation or monitoring purposes.Keywords: forest specialist, fragment size, frugivore, insectivore, isolation, land use, matrix, species richness

Biology students traditionally use a textbook in the field and on courses to identify species, but now a new mobile-application tool has been developed as an alternative. Guided by Self-Determination Theory (SDT) we conducted an experimental study to test the effect of the mobile-application, relative to the traditional textbook, on students' intrinsic motivation, perceived competence, and achievement. Seventy-one students were randomly assigned to either an experimental condition (mobile application - ArtsApp) or control condition (textbook - Lids flora). As hypothesised, the students using ArtsApp had higher intrinsic motivation, perceived competence, and achievement, compared to the textbook control group, with medium to large effect sizes. Furthermore, using the mobile application, relative to the textbook, predicted intrinsic motivation, which in turn, predicted higher achievement scores in a path analysis. Lastly in a hierarchical regression analysis, intrinsic motivation and autonomous motivation accounted over and above in students' interest for species identification, and importance of knowing species. These results are in line with SDT's theorising: emphasising that when students act out of interest, choice, and have an internal locus of causality, they achieve better outcomes, presumably because these satisfy students' psychological needs for autonomy, competence, and relatedness. Factors facilitating this are interest, choice, and feedback, which we argue are in-built functions in the mobile application as opposed to the textbook, and which might account for the positive results. Further studies with several student-groups and complex designs are needed before inferring causality across educational levels. Based on the present study, we recommend that biology teachers in higher education employ mobile application tools in species identification due to increases in motivation and a higher degree of accurate identification of sedges. Mobile-application enhances intrinsic motivation, perceived competence and achievement.Intrinsic motivation mediates mobile-application and achievement.Intrinsic motivation and autonomous motivation explains valuing of species identification.Results are in line with Self-Determination Theory.

Questions Is there a shift from positive to negative biotic interaction effects on seedling recruitment along two different stress gradients, temperature and precipitation (the stress-gradient hypothesis); do such interaction effects differ between species with different bioclimatic affinities? Location Boreal, sub-alpine and alpine grassland in southern Norway. Methods We tested the stress-gradient hypothesis by comparing seedling recruitment in bare-ground gaps where vegetation has been removed vs in extant grassland vegetation in 12 boreal, sub-alpine and alpine grassland sites along a precipitation gradient. This was tested in (1) a seed-sowing experiment and (2) in naturally occurring recruitment of alpine, generalist and boreal species. Results Emergence of the sown alpine species was higher in the cold alpine than in the warmer sub-alpine sites, with no effects of precipitation or vegetation removal. The sown generalists also decreased in emergence towards warmer sites, whereas there was no effect of temperature on the sown boreal species. Vegetation removal, interacting with precipitation, increased the emergence of the generalist and boreal species sown at intermediate precipitation levels. In contrast, interactions between temperature and vegetation removal regulated the emergence of all groups of naturally occurring seedlings. Alpine and generalist species emerged at the highest rate in alpine sites, whereas boreal species had highest emergence in the lowlands. Conclusion For all species groups, strong effects of vegetation removal show that competition from the extant vegetation dominates in controlling seedling emergence across all study sites and species. In generalist and boreal species, positive interactions between vegetation removal and temperature show that competitive interactions affect seedling emergence more strongly towards warmer climates, in line with the stress-gradient hypothesis. In contrast, alpine species show no such interactions. This suggests that species’ adaptations to climate, in combination with environmental forcing, control seedling emergence along the bioclimatic gradients. Our results have implications for nature conservation, as we propose that disturbance from grazing animals can be useful to release competition and thereby increase seedling recruitment and biodiversity in boreal and alpine grasslands in a warmer future.

The progression of key plant life-history events, such as spring leaf-out and flowering, along bioclimatic gradients in elevation and latitude is one of the more conspicuous patterns in nature, and, as such, it has served as a source of opportunity, industry, inspiration, and wonder for farmers, natural scientists, and artists alike (1⇓–3). For example, in many regions across the world, transhumance, traditional land-use practices that involve the seasonal movement of people and their livestock between fixed summer and winter pastures, has developed to exploit such phenological gradients across the landscape (2, 4, 5). These phenological patterns are tightly linked to temperature, leading to the formulation of bioclimatic “laws” about phenology (6). Advancing spring phenologies were also among the first clear empirical examples of biotic responses to a warming climate (7, 8). In PNAS, Vitasse et al. (9) show convincingly that climate change is now altering not only the timing of the phenological events but also the underlying patterns in phenology along environmental gradients, to an extent where these patterns are no longer in concordance with “Hopkins bioclimatic law” (6). In particular, the elevation-induced shift in the time of leaf-out in four common tree species in the Swiss Alps between low and high elevation has contracted by 35% from the 1960s until today (i.e., an increase in the rate of progression of spring leaf-out with elevation). Vitasse et al. (9) investigated three possible explanations for the observed discrepancy: ( i ) stronger warming at high elevation, ( ii ) stronger warming later in the season affecting plants at high elevation more because of later leaf-out, and ( iii ) changes in the number of chilling days (mean temperature of 0–8 °C between November and mean leaf-out date). Their analyses show that the number of chilling days during warmer winters has … [↵][1]1To whom correspondence should be addressed. Email: vigdis.vandvik{at}uib.no. [1]: #xref-corresp-1-1

Synthesising trait observations and knowledge across the Tree of Life remains a grand challenge for biodiversity science. Despite the well-recognised importance of traits for addressing ecological and evolutionary questions, trait-based approaches still struggle with several basic data requirements to deliver openly accessible, reproducible, and transparent science. Here, we introduce the Open Traits Network (OTN) – a decentralised alliance of international researchers and institutions focused on collaborative integration and standardisation of the exponentially increasing availability of trait data across all organisms. The OTN embraces the use of Open Science principles in trait research, particularly open data, open source, and open methodology protocols and workflows, to accelerate the synthesis of trait data across the Tree of Life. Increased efforts at all levels – from individual scientists, research networks, scientific societies, funding agencies, to publishers – are necessary to fully exploit the opportunities offered by Open Science in trait research. Democratising access to data, tools and resources will facilitate rapid advances in the biological sciences and our ability to address pressing environmental and societal demands.

The Arctic is warming twice as fast as the rest of the planet, leading to rapid changes in species composition and plant functional trait variation. Landscape-level maps of vegetation composition and trait distributions are required to expand spatially-limited plot studies, overcome sampling biases associated with the most accessible research areas, and create baselines from which to monitor environmental change. Unmanned aerial vehicles (UAVs) have emerged as a low-cost method to generate high-resolution imagery and bridge the gap between fine-scale field studies and lower resolution satellite analyses. Here we used field spectroscopy data (400–2500 nm) and UAV multispectral imagery to test spectral methods of species identification and plant water and chemistry retrieval near Longyearbyen, Svalbard. Using the field spectroscopy data and Random Forest analysis, we were able to distinguish eight common High Arctic plant tundra species with 74% accuracy. Using partial least squares regression (PLSR), we were able to predict corresponding water, nitrogen, phosphorus and C:N values (r 2 = 0.61–0.88, RMSEmean = 12%–64%). We developed analogous models using UAV imagery (five bands: Blue, Green, Red, Red Edge and Near-Infrared) and scaled up the results across a 450 m long nutrient gradient located underneath a seabird colony. At the UAV level, we were able to map three plant functional groups (mosses, graminoids and dwarf shrubs) at 72% accuracy and generate maps of plant chemistry. Our maps show a clear marine-derived fertility gradient, mediated by geomorphology. We used the UAV results to explore two methods of upscaling plant water content to the wider landscape using Sentinel-2A imagery. Our results are pertinent for high resolution, low-cost mapping of the Arctic.

How plants allocate biomass to different parts strongly affects vegetation dynamics and ecosystem processes and services such as productivity and carbon storage. We tested the hypothesis that plant size explains the majority of variation in the size of plant parts (as predicted by allometric partitioning theory, APT) and that additional variation is explained by optimal responses for a given individual reproductive state and environment (as predicted by optimal partitioning theory, OPT) for alpine-lowland species pairs from three genera of grassland plants (Veronica, Viola and Carex) sampled along orthogonal gradients in temperature and precipitation. We found general patterns of allometric scaling (allometric exponents) of roots, stems, leaves and flowers, more or less as predicted by APT, and these patterns remained fairly constant across temperature and precipitation gradients. In contrast, basic allocation (allometric coefficients) was clearly related to climate, such as less allocation to leaves but more to roots, stems and flowers with increasing temperatures, in accordance with OPT. Furthermore, our results show that basic allocation is related to habitat affinity (alpine, lowland) and individual life-history states (reproductive or not) and that there is greater variability in small plants, which suggests that biomass partitioning theory should consider both the life-history and ecology of small plants to accurately predict climate-related grassland plant allocation and its implications.

Biotic interactions are often ignored in assessments of climate change impacts. However, climate-related changes in species interactions, often mediated through increased dominance of certain species or functional groups, may have important implications for how species respond to climate warming and altered precipitation patterns. We examined how a dominant plant functional group affected the population dynamics of four co-occurring forb species by experimentally removing graminoids in seminatural grasslands. Specifically, we explored how the interaction between dominants and subordinates varied with climate by replicating the removal experiment across a climate grid consisting of 12 field sites spanning broad-scale temperature and precipitation gradients in southern Norway. Biotic interactions affected population growth rates of all study species, and the net outcome of interactions between dominants and subordinates switched from facilitation to competition with increasing temperature along the temperature gradient. The impacts of competitive interactions on subordinates in the warmer sites could primarily be attributed to reduced plant survival. Whereas the response to dominant removal varied with temperature, there was no overall effect of precipitation on the balance between competition and facilitation. Our findings suggest that global warming may increase the relative importance of competitive interactions in seminatural grasslands across a wide range of precipitation levels, thereby favouring highly competitive dominant species over subordinate species. As a result, seminatural grasslands may become increasingly dependent on disturbance (i.e. traditional management such as grazing and mowing) to maintain viable populations of subordinate species and thereby biodiversity under future climates. Our study highlights the importance of population-level studies replicated under different climatic conditions for understanding the underlying mechanisms of climate change impacts on plants.

Background: Newly protected, tropical forests recovering from logging and clearance are increasingly important targets for conservation. Recovery is typically evaluated or monitored by using a few easily identified species groups, but this may not be sufficient as unmonitored groups of equivalent ecological importance are unlikely to respond in a similar manner due to physiological or dispersal differences. Aims: We compared four groups of plants: large trees, shrubs and saplings, herbs and ferns in a forest recovering from disturbance. We quantified the relative importance of disturbance history and local environmental conditions in determining species richness and community composition of these groups and assessed whether the groups could act as surrogate indicators for one another. Methods: Vegetation was surveyed on a gradient of disturbance intensity and recovery time (20–60 years) in Mabira Forest, Uganda. We looked for correlations between species groups in richness or composition across sites and used constrained ordinations to identify important environmental variables. Results: Neither species richness nor composition patterns were correlated between groups. All groups were weakly related to disturbance history; trees and shrubs were related to soil, herbs to microhabitat and ferns to microclimate. Conclusions: No group acted as an indicator for another. The relative influence of disturbance and local environmental effects varied in the manner predicted, with disturbance stronger for trees and environment stronger for ferns.

Tree growth at the treeline ecotone is known to be sensitive to climate variability and is thus considered to be a worldwide biomonitor of climate change. However, our understanding of within-region variation in growth responses through space and time is limited. A dry south-facing slope dominated by Pinus wallichiana A.B. Jacks. and a wet north-facing slope dominated by Abies spectabilis (D. Don) Spach in Nepal, central Himalaya, were used to analyze the intersite (i.e., dry vs. wet sites) and intrasite (i.e., treeline vs. forest line elevations) tree-growth relationships, as well as response to monthly and seasonal temperature and precipitation at annual and bidecadal time scales. At both study sites and at two elevations within each site, growth can be strongly affected by growing-season and nongrowing-season factors; however, there are inconsistencies in terms of the climate–growth relationship across space and over time. At the dry site, only a weak positive growth response to summer temperature is observed. At both sites, there is a negative growth response to winter precipitation at both high and low elevations, and this response is markedly independent of the summer and winter temperature trends of the respective site. At the wet site, growth at the higher elevation is negatively correlated to the early summer temperature, whereas a positive growth response to spring precipitation is observed at the lower elevation, indicating a possible drought effect. The results illustrate how different climatic drivers may govern tree-growth responses both between sites with contrasting climates within a region and along elevational gradients within the treeline ecotone. This underlines the need for multiscale studies and a focus on multiple climate variables when analyzing treeline ecotone responses to climate change.

Effective evidence-based nature conservation and habitat management relies on developing and refining our methodological toolbox for detecting critical ecological changes at an early stage. This requires not only optimizing the use and integration of evidence from available data, but also optimizing methods for dealing with imperfect knowledge and data deficiencies. For policy and management relevance, ecological data are often synthesized into indicators, which are assessed against reference levels and limit values. Here we explore challenges and opportunities in defining ecological condition in relation to a reference condition reflecting intact ecosystems, as well as setting limit values for good ecological condition, linked to critical ecological thresholds in dose–response relationships between pressures and condition variables. These two concepts have been widely studied and implemented in aquatic sciences, but rarely in terrestrial systems. In this paper, we address practical considerations, theoretical challenges and possible solutions using different approaches to determine reference and limit values for good ecological condition in terrestrial ecosystems, based on empirical experiences from a case study in central Norway. We present five approaches for setting indicator reference values for intact ecosystems: absolute biophysical boundaries, reference areas, reference communities, ecosystem dynamics based models, and habitat availability based models. We further present four approaches for identifying indicator limit values for good ecological condition: empirically estimated values, statistical distributions, assumed linear relationships, and expert judgement-based limits. This exercise highlights the versatile and robust nature of ecological condition assessments based on reference and limit values for different management purposes, for situations where knowledge of the underlying relationships is lacking, and for situations limited by data availability. Ecological condition Index Management Reference condition Terrestrial This is an open access article distributed under the terms of the Creative Commons CC-BY license, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

In the version of this Perspective originally published, the first author of reference 39 was incorrectly listed as W. Cornwell and the publication year was incorrect. The reference should have read as follows: “Flores-Moreno, H. et al. fungaltraits aka funfun: a dynamic functional trait database for the world's fungi (GitHub, 2019); https://doi.org/10.5281/zenodo.1216257”. This has now been corrected.

Aim Previous research on how climatic niches vary across species ranges has focused on a limited number of species, mostly invasive, and has not, to date, been very conclusive. Here we assess the d ...

In imbibing seeds, resumption of metabolism leads to the unavoidable release of volatile by-products that are perceived as cues by rodent seed predators. The crypsis hypothesis proposes that the primary function of a water-impermeable, hard seed coat is to reduce rodent seed predation by rendering seeds olfactorily cryptic. In an opinion paper, Jayasuriya et al. (2015) find the crypsis hypothesis unscientific and ‘not consistent with Darwin's theory of evolution by natural selection’. It is unfortunate that Jayasuriya et al. (2015) did not appreciate that the crypsis hypothesis offers an alternative explanation for the evolution of water-impermeable seeds: released seed volatiles are cues used by rodents to locate seeds, and variation in seed-coat permeability leading to differences in seed volatile release represents the variable under selection. Furthermore, the sealing of water-impermeable seed coats imposes a cost of increased generation time and, therefore, dormancy-release mechanisms are expected to subsequently evolve in response to local environmental conditions. We also disagree with most other claims by Jayasuriya et al. (2015), who failed to appreciate how species with dimorphic seeds – one morph with permeable and the other with impermeable seed coats – benefit from rodent caching behaviour and population dynamics. We welcome this opportunity to clarify and elaborate on key features and the evolution of water-impermeable seed coats according to the crypsis hypothesis.

Seedling recruitment is a critical life history stage for trees, and successful recruitment is tightly linked to both abiotic factors and biotic interactions. In order to better understand how tree species’ distributions may change in response to anticipated climate change, more knowledge of the effects of complex climate and biotic interactions is needed. We conducted a seed-sowing experiment to investigate how temperature, precipitation and biotic interactions impact recruitment of Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) seedlings in southern Norway. Seeds were sown into intact vegetation and experimentally created gaps. To study the combined effects of temperature and precipitation, the experiment was replicated across 12 sites, spanning a natural climate gradient from boreal to alpine and from sub-continental to oceanic. Seedling emergence and survival were assessed 12 and 16 months after sowing, respectively, and aboveground biomass and height were determined at the end of the experiment. Interestingly, very few seedlings were detected in the boreal sites, and the highest number of seedlings emerged and established in the alpine sites, indicating that low temperature did not limit seedling recruitment. Site precipitation had an overall positive effect on seedling recruitment, especially at intermediate precipitation levels. Seedling emergence, establishment and biomass were higher in gap plots compared to intact vegetation at all temperature levels. These results suggest that biotic interactions in the form of competition may be more important than temperature as a limiting factor for tree seedling recruitment in the sub- and low-alpine zone of southern Norway. acceptedVersion

Forest-dependent biodiversity is threatened throughout the tropics by habitat loss and land-use intensification of the matrix habitats. We resampled historic data on two moth families, known to play central roles in many ecosystem processes, to evaluate temporal changes in species richness and community structure in three protected forests in central Uganda in a rapidly changing matrix. Our results show some significant declines in the moth species richness and the relative abundance and richness of forest-dependent species over the last 20–40 years. The observed changes in species richness and composition among different forests, ecological types, and moth groups highlight the need to repeatedly monitor biodiversity even within protected and relatively intact forests. publishedVersion

Palaeoecology and ecology have a lot in common. However, the two disciplines have evolved almost separately, leading to an ongoing debate on how to link them better, as both would undoubtedly benefit from a higher degree of cross-fertilisation of ideas, research insights and questions. In this paper, we explore similarities and differences in the two branches of ecology over the past 40 years by assessing the publication output from an unusually large cohort of ‘academic siblings’ – researchers in ecology and palaeoecology who all share one of the strongest career-shaping influences on researchers; their supervisor. This was made possible by John Birks’ long and active career within ecology and palaeoecology, and his supervision of a large number of students in both fields ( n = 12 and 21, respectively). Among them, John Birks’ academic progeny has published 934 papers in the international peer-reviewed literature. We collected information on the year, titles, keywords and journals of all these publications and used these data to assess the extent of, and find potential explanations for, the historical and present-day separation of ecology and palaeoecology. Despite considerable thematic overlap, there is a real and possibly widening division between the two branches that is visible both at the scale of individual research careers, journals and papers. We argue that rather than being unique to the relationship between palaeoecology and ecology, this reflects trends for thematic and methodological specialisation evident across the research landscape. We propose that both individual researchers and journals would benefit from, and can contribute to, closing the gaps developing between various ‘special branches’ in science. A good title, an informative abstract, a careful and thought-through selection of keywords and a focus on readability and avoidance of jargon will likely improve readership and impact both within one’s own ‘special branch’ and beyond.

Aims We investigated the treeline dynamics of two environmentally contrasting areas in the Nepalese Himalaya to address the following questions: (i) Does the timing of establishment of the current treeline differ between the two study areas, and can area-specific treeline developments be identified? (ii) Do recruitment patterns and height growth indicate recent climate-driven treeline advance, following the general prediction for the central Himalayan region, in the two study areas? Methods A dry-climate treeline dominated by Pinus wallichiana and a mesicclimate treeline with Abies spectabilis were selected for study. In each area, we sampled the size and age structure of the study species along three elevational transects (20-m wide) from the forest line to the tree species line crossing the treeline. We also sampled treeline trees from within and outside transects to reconstruct past treeline establishment dynamics.

Seed banks contribute to forest regeneration after disturbance, but less is known about fern spore banks, particularly in a paleotropical context. We sampled the buried seed and fern spore bank in Mabira Forest, a 300 km2 forest in central Uganda, to explore the effect of time since disturbance. Soil cores (5 cm depth) were taken from 39 plots across three different classes of ‘recovery’: (1) not disturbed since 1950; (2) logged between 1950 and 1980; and (3) cleared for agriculture between 1970 and 1990 but reforested since. Plant emergence was monitored in a glasshouse. We predicted that the seed bank would reflect time since disturbance, with more pioneer species in recently disturbed stands, and that the fern spore bank would reflect stand age less closely due to greater dispersal capacity. We recorded a median 752 seeds per square meter, most of which were trees; the most abundant species was the invasive tree Broussonetia papyrifera. The fern spore bank was twice as dense, but 95 percent of fern spores were of one species, Christella parasitica. Tree seed density was significantly affected by time since disturbance with fewer seeds in the older stands. Herb seed density, fern spore density, and species richness for all groups were not significantly affected by time since disturbance. Neither seed bank nor fern spore bank closely resembled the aboveground vegetation. We compared our results to existing literature on seed banks in tropical forests, finding that our densities are relatively high for African forests, but low compared to the Neotropics and Australia. RESUME Les banques de graines contribuent a la regeneration des forets apres perturbation, mais nous savons encore peu de choses au sujet des banques de spores de fougeres, particulierement dans un contexte paleotropical. Nous avons enregistre les graines ainsi que les spores de fougeres enterrees dans la foret de Mabira, une foret de 300 km² au centre de l'Ouganda, et explore l'impact du temps passe depuis une perturbation. Les echantillons de terre ont ete preleves jusqu’a 5 cm de profondeur dans 39 parcelles caracterisees par differents degres de “reconstruction”: non perturbee depuis 1950, exploitee entre 1950 et 1980, et deboisee pour des fins d'agriculture entre 1970 et 1990 puis reboisee. L’emergence a ete suivie dans une serre. Nous avons predit que la banque de graines allait refleter le temps passe depuis la perturbation, avec davantage d'especes pionnieres dans les parcelles recemment perturbees, mais que ce patron serait moins remarquable pour la banque de spores en raison de meilleures capacites de dispersion. Nous avons enregistre une mediane de 752 graines par metre carre, dons la plupart etaient des graines d'arbres ; la graine la plus abondante etait le petit arbre invasif Broussonetia papyrifera. La banque de spores de fougeres etait deux fois plus dense mais 95 pourcent de ces spores appartenaient a une seule espece, Christella parasitica. La densite de graines d'arbres etait significativement affectee par le temps passe depuis la perturbation, avec moins de graines dans les parcelles les plus anciennes. La densite de graines d'herbes, la densite de spores de fougeres et la richesse specifique pour tous les groupes n’etaient pas significativement affectees par le temps passe depuis la perturbation. Ni la banque de graines, ni la banque de spores de fougeres ne ressemblait vraiment a la vegetation de surface. Nous avons compare nos resultats a la litterature existant sur les banques de graines en foret tropicale, et trouve que nos densites etaient relativement fortes par rapport aux forets africaines, mais basses comparees aux forets neotropicales et australiennes.