Urs A. Treier

I am an evolutionary ecologist interested in factors and evolutionary processes that determine the abundance and structure of plant populations.

Ecoinformatics & Biodiversity

Department of Bioscience

Aarhus University

Ny Munkegade 116, Building 1540

DK-8000 Aarhus C

Denmark

mail –  webpage

Current Research

Unmanned Aerial Systems (UAS or drones) give us the unique opportunity to map and monitor vegetation at ultra-high resolution on demand. Furthermore, UAS-based remote sensing will enable us to bridge the scale gap between field-based observations and satellite-based observations. I am responsible for all technical aspects of our drones and the sensors they carry as well as for flying the drones. Furthermore, I am involved in both the image- and field-based research, which aims at understanding vegetation dynamics in arctic ecosystems. Thus, my current field of research is “drone ecology” (the use of drones to answer ecological questions) and I spend most of my summers in remote areas of Greenland to collect ground-based ecological data and to map the tundra vegetation with a drone equipped with different sensors.

Quadrocopter with RedEdge(TM), Tasiilaq, Greenland (photo-copyright: Normand-Treier)Our quadcopter with multispectral sensor, Tasiilaq, east Greenland
13. Arthropod Sampling (photo-copyright: Normand-Treier)  

13. Meter scale variation in shrub dominance and soil moisture structure Arctic arthropod communities

Hansen RR, Hansen OLP, Bowden JJ, Treier UA, Normand S & Høye T
PeerJ, 4: e2224 (2016).

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The Arctic is warming at twice the rate of the rest of the world. This impacts Arctic species both directly, through increased temperatures, and indirectly, through structural changes in their habitats. Species are expected to exhibit idiosyncratic responses to structural change, which calls for detailed investigations at the species and community level. Here, we investigate how arthropod assemblages of spiders and beetles respond to variation in habitat structure at small spatial scales. We sampled transitions in shrub dominance and soil moisture between three different habitats (fen, dwarf shrub heath, and tall shrub tundra) at three different sites along a fjord gradient in southwest Greenland, using yellow pitfall cups. We identified 2,547 individuals belonging to 47 species. We used species richness estimation, indicator species analysis and latent variable modeling to examine differences in arthropod community structure in response to habitat variation at local (within site) and regional scales (between sites). We estimated species responses to the environment by fitting species-specific generalized linear models with environmental covariates. Species assemblages were segregated at the habitat and site level. Each habitat hosted significant indicator species, and species richness and diversity were significantly lower in fen habitats. Assemblage patterns were significantly linked to changes in soil moisture and vegetation height, as well as geographic location. We show that meter-scale variation among habitats affects arthropod community structure, supporting the notion that the Arctic tundra is a heterogeneous environment. To gain sufficient insight into temporal biodiversity change, we require studies of species distributions detailing species habitat preferences.

 

Keywords: Biodiversity • Biogeography • Conservation Biology • Ecology • Entomology
12. A greener Greenland? (photo-copyright: Normand-Treier)  

12. A greener Greenland? Climatic potential and long-term constraints on future expansions of trees and shrubs

Normand S, Randin C, Ohlemüller R, Bay C, Høye TT, Kjær ED, Körner C, Lischke H, Maiorano L, Paulsen J, Pearman PB, Psomas A, Treier UA, Zimmermann NE & Svenning JC
Philosophical Transactions B: Biological Sciences, 368 (1624): 20120479 (2013).

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Warming-induced expansion of trees and shrubs into tundra vegetation will strongly impact Arctic ecosystems. Today, a small subset of the boreal woody flora found during certain Plio- Pleistocene warm periods inhabits Greenland. Whether the 21st century warming will induce a re-colonisation of a rich woody flora depends on the roles of climate and migration limitations in shaping species ranges. Using potential tree-line and climatic niche modelling, we project shifts in areas climatically suitable for tree growth and 56 Greenlandic, North American and European tree and shrub species from the Last Glacial Maximum through the present and into the future. In combination with observed tree plantings, our modelling highlights that a majority of the non-native species find climatically suitable conditions in certain parts of Greenland today, even in areas harbouring no native trees. Analyses of analog climates indicate that these conditions are widespread outside Greenland, thus increasing the likelihood of woody invasions. Nonetheless, we find a substantial migration lag for Greenland’s current and future woody flora. In conclusion, the projected climatic scope for future expansions is strongly limited by dispersal, soil development, and other disequilibrium dynamics, with plantings and unintentional seed dispersal by humans having potentially large impacts on spread rates.

 

Keywords: arctic • climatic niche modelling • climate change impact • disequilibrium • postglacial re-colonisation • shrub expansion
11. cp-DNA alignment  

11. A set of 100 chloroplast DNA primer pairs to study population genetics and phylogeny in monocotyledons

Scarcelli N, Barnaud A, Eiserhardt W, Treier UA, Seveno M, d’Anfray A, Vigouroux Y & Pintaud J-C
PLoS ONE, 6(5): e19954 (2011).

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Chloroplast DNA sequences are of great interest for population genetics and phylogenetic studies. However, only a small set of markers are commonly used. Most of them have been designed for amplification in a large range of Angiosperms and are located in the Large Single Copy (LSC). Here we developed a new set of 100 primer pairs optimized for amplification in Monocotyledons. Primer pairs amplify coding (exon) and non-coding regions (intron and intergenic spacer). They span the different chloroplast regions: 72 are located in the LSC, 13 in the Small Single Copy (SSC) and 15 in the Inverted Repeat region (IR). Amplification and sequencing were tested in 13 species of Monocotyledons: Dioscorea abyssinica, D. praehensilis, D. rotundata, D. dumetorum, D. bulbifera, Trichopus sempervirens (Dioscoreaceae), Phoenix canariensis, P. dactylifera, Astrocaryum scopatum, A. murumuru, Ceroxylon echinulatum (Arecaceae), Digitaria excilis and Pennisetum glaucum (Poaceae). The diversity found in Dioscorea, Digitaria and Pennisetum mainly corresponded to Single Nucleotide Polymorphism (SNP) while the diversity found in Arecaceae also comprises Variable Number Tandem Repeat (VNTR). We observed that the most variable loci (rps15-ycf1, rpl32-ccsA, ndhF-rpl32, ndhG-ndhI and ccsA) are located in the SSC. Through the analysis of the genetic structure of a wild-cultivated species complex in Dioscorea, we demonstrated that this new set of primers is of great interest for population genetics and we anticipate that it will also be useful for phylogeny and bar-coding studies.

 

Keywords: Chloroplast • microsatellite • minisatellite • monocotyledon • primer • ArecaceaeDioscoreaPennisetumDigitaria

10. Veratrum in the southern Urals (photo-copyright: Ivan Sarapultsev)  

10. Differential effects of historical migration, glaciations and human impact on the genetic structure and diversity of the mountain pasture weed Veratrum album L.

Treier UA & Müller-Schärer H
Journal of Biogeography, 38(9): 1776–1791 (2011).

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Aim Today’s genetic population structure and diversity of species can be understood as the result of range expansion from the area of origin, past climatic oscillations and contemporary processes. We examined the relative importance of these factors in Veratrum album L., a toxic weed of mountain grasslands.

Location Continental Europe.

Methods Forty populations from the Asian border (Urals and Caucasus) to Portugal were studied using amplified fragment length polymorphisms (AFLPs) combined with selected plant and population measures. The data were analysed with phylogenetic, population genetic and regression methods inferring both genetic structure and diversity from geographic and ecological factors.

Results Fragment frequency clines together with genetic distance clustering and principal coordinates analysis indicated an east–west direction in the genetic structure of V. album, suggesting ancient migration into Europe from a proposed Asian origin. However, the strong geographic pattern in the genetic structure, pronounced isolation by distance (R2 = 0.74) and moderate overall population differentiation (FST = 0.13) suggests high historical gene flow, possibly during glacials, and vicariance into mountainous regions during interglacials. Occurrence of V. album during the last glaciation in several areas along the periphery of the Alps and recolonization of this mountain range from both eastern and central–western areas was indicated. Genetic diversity was highest in central Europe, a pattern that did not agree with the expectations from east–west migration into Europe. Furthermore, managed habitats showed higher levels of genetic diversity compared to unmanaged habitats. Stepwise linear regression determined shoot density and soil phosphorus as the main predictors of within-population genetic diversity (R2 = 0.40).

Main conclusions Our results showed that V. album retained genetic imprints of historical range expansion into Europe, although this was alleviated by the influence of climatic oscillations and contemporary processes. For example, genetic population structure was strongly affected by post-glacial vicariance while patterns of genetic diversity seemed mainly to be influenced by human land use. Our findings highlight the importance of applying a synthetic approach, testing the influence of both historical and contemporary processes on genetic structure and diversity in order to understand complex phylogeographic patterns. This may especially apply to widespread species, such as weeds. Implications of our findings for biological control are briefly discussed.

 

Keywords: Alpine grassland • biological control • ecological factors • false hellebore • genetic diversity • geographic origin • ice ages • Liliales • phylogeography • Quaternary

9. Picea abies tree  (photo-copyright: Normand-Treier)  

9. Tree refugia and slow forest development in response to post-LGM warming in North-Eastern European Russia

Normand S, Treier UA & Odgaard BV
Frontiers of Biogeography, 2.4: 91-93 (2011).

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The paper provides a commentary on the paleoecological study by Väliranta et al. (2011, Journal of Biogeography) and a minireview on open questions such as: How far north did tree species survive the Last Glacial Maximum (LGM, ca. 21kya)? How fast did tree species spread and thus current forest structure develop during post-LGM warming? We conclude that in order to understand the spread of boreal tree and other plant species with post-LGM warming, the areas of the Russian plain and Ural need special attention.

 

Keywords: Last Glacial Maximum (LGM) • post-LGM warming • boreal trees • Russian plain • Reid’s paradox • fossil record • migration • dispersal

8. Chromosomes of a hexaploid Centaurea stoebe plant (photo-copyright: Patrik Mráz)  

8. Polyploidy in phenotypic space and invasion context: a morphometric study of Centaurea stoebe s.l.

Mráz P, Bourchier RS, Treier UA, Schaffner U & Müller-Schärer H
International Journal of Plant Sciences, 172(3): 386-402 (2011).

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The taxonomy of the Centaurea stoebe complex is controversial. Diploid and tetraploid plants occur in its native European range, but to date only tetraploids have been recorded from its introduced range in North America. We examined morphological differentiation of C. stoebe using multivariate and univariate approaches to clarify the taxonomic status of the known cytotypes. We measured more than 40 morphological traits on plants originating from 78 populations, grown from seed under uniform glasshouse conditions. The ploidy of almost 300 plants from 2 native and 20 introduced populations from Canada was assessed to test for the absence of diploids from North America. Finally, we explored whether postintroduction processes have resulted in phenotypic changes in introduced plants which may have contributed to the invasion success of C. stoebe. Morphometric analyses showed a clear separation of 2x and 4x plants and thus supported recognition of both cytotypes as separate taxa. Differences in the life cycle, the number of florets, the shape of capitula, and the shape of young rosette leaves were the best discriminant characters. Only minor differences were found between native and introduced tetraploids. All plants from the introduced range except for one hexaploid were found to be tetraploid. Rare diploids from Canada were identified as Centaurea diffusa or Centaurea psamogenna.

 

Keywords: Asteraceae • biological invasion • flow cytometry • karyology • multivariate morphometrics • polyploidy • spotted knapweed

7. Centaurea stoebe (photo-copyright: Normand-Treier)  

7. Evidence for a combination of pre-adapted traits and rapid adaptive change in the invasive plant Centaurea stoebe

Henery ML, Bowman G, Mráz P, Treier, UA, Gex-Fabry E, Schaffner U & Müller-Schärer H

Journal of Ecology, 98(4): 800-813 (2010).

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1. Introduced plants have the potential to rapidly evolve traits of ecological importance that may add to their innate potential to become invasive. During invasions, selection may favour genotypes that are already pre-adapted to conditions in the new habitat and, over time, alter the characteristics of subsequent generations.

 

2. Spotted knapweed (Centaurea stoebe) occurs in two predominantly spatially separated cytotypes in its native range (Europe–Western Asia), but currently only the tetraploid form has been confirmed in the introduced range (North America), where it is invasive. We used several common garden experiments to examine, across multiple populations, whether tetraploids and diploids from the native range differ in life cycle, leaf traits and reproductive capacity and if such differences would explain the predominance of tetraploids and their advance into new habitats in the introduced range. We also compared the same traits in tetraploids from the native and introduced range to determine whether any rapid adaptive changes had occurred since introduction that may have enhanced invasive potential of the species in NorthAmerica.

 

3. We found tetraploids had lower specific leaf area, less lamina dissection and fewer, narrower leaves than diploids. Diploids exhibited a monocarpic life cycle and produced few if any accessory rosettes. Diploids produced significantly more seeds per capitulum and had more capitula per plant than tetraploids. In contrast, the vast majority of European tetraploids continued to flower in both seasons by regenerating from multiple secondary rosettes, demonstrating a predominantly polycarpic life cycle.

 

4. During early growth tetraploids from NorthAmerica achieved greater biomass than both tetraploids and diploids from the native range but this did not manifest as larger above-ground biomass at maturity. In NorthAmerican tetraploids there was also evidence of a shift towards a more strictly polycarpic life cycle, less leaf dissection, greater carbon investment per leaf, and greater seed production per capitulum.

 

5. Synthesis. Our results suggest that the characteristics of tetraploid C. stoebe pre-adapted them (compared to diploid conspecifics) for spread and persistence of the species into habitats in North America characterized by a more continental climate. After the species’ introduction, small but potentially important shifts in tetraploid biology have occurred that may have contributed significantly to successful invasion.

 

Keywords: biological invasion • Centaurea stoebe • plant life cycle • plant traits • ploidy • rapid adaptive change • reproductive potential

6. Carex flacca (photo-copyright: Normand-Treier)  

6. Importance of abiotic stress as a range-limit determinant for European plants: insights from species' responses to climatic gradients

Normand S, Treier UA, Randin C, Vittoz P, Guisan A & Svenning JC

Global Ecology and Biogeography, 18(4): 437-449 (2009).

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Aim: We examined whether species occurrences are primarily limited by physiological tolerance in the abiotically more stressful end of climatic gradients (the asymmetric abiotic stress limitation (AASL) hypothesis) and the geographical predictions of this hypothesis: abiotic stress mainly determines upper-latitudinal and upper-altitudinal species range limits, and the importance of abiotic stress for these range limits increases the further northwards and upwards a species occurs.

 

Location: Europe and the Swiss Alps.

 

Methods: The AASL hypothesis predicts that species have skewed responses to climatic gradients, with a steep decline towards the more stressful conditions. Based on presence–absence data we examined the shape of plant species responses (measured as probability of occurrence) along three climatic gradients across latitudes in Europe (1577 species) and altitudes in the Swiss Alps (284 species) using Huisman–Olff–Fresco, generalized linear and generalized additive models.

 

Results: We found that almost half of the species from Europe and one-third from the Swiss Alps showed responses consistent with the predictions of the AASL hypothesis. Cold temperatures and a short growing season seemed to determine the upper-latitudinal and upper-altitudinal range limits of up to one-third of the species, while drought provided an important constraint at lower-latitudinal range limits for up to one-fifth of the species. We found a biome-dependent influence of abiotic stress and no clear support for abiotic stress as a stronger upper range-limit determinant for species with higher latitudinal and altitudinal distributions. However, the overall influence of climate as a range-limit determinant increased with latitude.

 

Main conclusions: Our results support the AASL hypothesis for almost half of the studied species, and suggest that temperature-related stress controls the upper-latitudinal and upper-altitudinal range limits of a large proportion of these species, while other factors including drought stress may be important at the lower range limits.

 

Keywords: Biotic interactions • climate • Europe • HOF models • physiological tolerance • plant species • response curves • spatial scale • Swiss Alps

5. Centaurea maculosa syn. C. stoebe (photo-copyright: Normand-Treier)  

5. Shift in cytotype frequency and niche space in the invasive plant Centaurea maculosa

Treier UA, Broennimann O, Normand S, Guisan A, Schaffner U, Steinger T & Müller-Schärer H

Ecology, 90(5): 1366-1377 (2009).

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Polyploidy is often assumed to increase the spread and thus the success of alien plant species, but few empirical studies exist. We tested this hypothesis with Centaurea maculosa Lam., a species native to Europe and introduced into North America approximately 120 years ago where it became highly invasive. We analyzed the ploidy level of more than 2000 plants from 93 native and 48 invasive C. maculosa populations and found a pronounced shift in the relative frequency of diploid and tetraploid cytotypes. In Europe diploid populations occur in higher frequencies than tetraploids and only four populations had both cytotypes, while in North America diploid plants were found in only one mixed population and thus tetraploids clearly dominated. Our results showed a pronounced shift in the climatic niche between tetraploid populations in the native and introduced range toward drier climate in North America and a similar albeit smaller shift between diploids and tetraploids in the native range. The field data indicate that diploids have a predominately monocarpic life cycle, while tetraploids are often polycarpic. Additionally, the polycarpic life-form seems to be more prevalent among tetraploids in the introduced range than among tetraploids in the native range. Our study suggests that both ploidy types of C. maculosa were introduced into North America, but tetraploids became the dominant cytotype with invasion. We suggest that the invasive success of C. maculosa is partly due to preadaptation of the tetraploid cytotype in Europe to drier climate and possibly further adaptation to these conditions in the introduced range. The potential for earlier and longer seed production associated with the polycarpic life cycle constitutes an additional factor that may have led to the dominance of tetraploids over diploids in the introduced range.

 

Keywords: alien species • biogeography • biological invasion • Centaurea stoebe • ecological niche • ecological tolerance • flow cytometry • niche breadth • niche shift • ploidy • polyploidization • spotted knapweed

4. Senecio vulgaris infected by Puccinia lagenophorae (photo-copyright: Nigel D. Paul)  

4. Testing the evolution of increased competitive ability (EICA) hypothesis in a novel framework

Handley RJ, Steinger T, Treier UA & Müller-Schärer H

Ecology, 89(2): 407-417 (2008).

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The “evolution of increased competitive ability” (EICA) hypothesis proposes that escape from natural enemies, e.g., after transcontinental introductions, alters the selection regime because costly defenses no longer enhance fitness. Such an evolutionary loss of defenses enables resources to be directed toward growth or other traits improving performance. We tested the EICA hypothesis in a novel framework in which the natural enemy is the traveler that follows its widespread host by accidental or deliberate (biocontrol) introductions. In a greenhouse experiment we used populations of Senecio vulgaris from North America, Europe, and Australia that differ in the history of exposure to the rust fungus Puccinia lagenophorae. Contrary to what is predicted by EICA, we found no evidence for increased levels of resistance to the rust fungus in plant populations with a longer history of rust exposure (Australia). Similarly, there was no evidence for reduced fecundity in these populations, although vegetative vigor, measured as secondary branching and growth rate, was lower. The maintenance of high rust resistance in populations with no (North America) or only a short history (Europe) of rust exposure is surprising given that resistance seems to incur considerable fitness costs, as indicated by the negative association between family mean resistance and fitness in the absence of disease observed for all three continents. The comparison of population differentiation in quantitative traits with estimates of differentiation in amplified fragment length polymorphic (AFLP) markers suggests that a number of fitness-related traits are under divergent selection among the studied populations. The proposed framework to test changes in the evolutionary trajectory underlying EICA can be employed in an expanded range of systems. These may include investigations on a cosmopolitan weed or crop when an antagonist is expanding its geographic range (such as our study), studies along a chronosequence of introduction time with expected increasing accumulation of natural enemies over time, or comparisons between introduced plant populations that differ in exposure time to biocontrol organisms.

 

Keywords: common groundsel • differences in exposure time to a plant pathogen • evolution of increased competitive ability • EICA • fitness costs • molecular markers • Puccinia lagenophorae • resistance • rust fungus • selection differentials • Senecio vulgaris

3. Old olive tree (Olea europaea) on Crete (photo-copyright: Normand-Treier)  

3. Polyploidy in the olive complex (Olea europaea L.): evidence from flow cytometry and nuclear microsatellite analyses

Besnard G, García-Verdugo C, Rubio de Casas R, Treier UA, Galland N & Vargas P

Annals of Botany, 101(1): 25-30 (2008).

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Background: Phylogenetic and phylogeographic investigations have been previously performed to study the evolution of the olive tree complex (Olea europaea). A particularly high genomic diversity has been found in north-west Africa. However, to date no exhaustive study has been addressed to infer putative polyploidization events and their evolutionary significance in the diversification of the olive tree and its relatives.

 

Methods: Representatives of the six olive subspecies were investigated using (a) flow cytometry to estimate genome content, and (b) six highly variable nuclear microsatellites to assess the presence of multiple alleles at co-dominant loci. In addition, nine individuals from a controlled cross between two individuals of O. europaea subsp. maroccana were characterized with microsatellites to check for chromosome inheritance.

 

Key Results: Based on flow cytometry and genetic analyses, strong evidence for polyploidy was obtained in subspp. cerasiformis (tetraploid) and maroccana (hexaploid), whereas the other subspecies appeared to be diploids. Agreement between flow cytometry and genetic analyses gives an alternative approach to chromosome counting to determine ploidy level of trees. Lastly, abnormalities in chromosomes inheritance leading to aneuploid formation were revealed using microsatellite analyses in the offspring from the controlled cross in subsp. maroccana.

 

Conclusions: This study constitutes the first report for multiple polyploidy in olive tree relatives. Formation of tetraploids and hexaploids may have played a major role in the diversification of the olive complex in north-west Africa. The fact that polyploidy is found in narrow endemic subspecies from Madeira (subsp. cerasiformis) and the Agadir Mountains (subsp. maroccana) suggests that polyploidization has been favoured to overcome inbreeding depression. Lastly, based on previous phylogenetic analyses, we hypothesize that subsp. cerasiformis resulted from hybridization between ancestors of subspp. guanchica and europaea.

 

Keywords: Flow cytometry • hexaploidy • High Atlas • Macaronesia • Olea europaea • olive • SSR • tetraploidy

2. Niche shift (PCA, Fig. 1 in Broennimann et al 2007, Ecol Lett)  

2. Evidence of climatic niche shift during biological invasion

Broennimann O, Treier UA, Müller-Schärer H, Thuiller W, Peterson AT & Guisan A

Ecology Letters, 10(8): 701-709. (2007)

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Niche-based models calibrated in the native range by relating species observations to climatic variables are commonly used to predict the potential spatial extent of species' invasion. This climate matching approach relies on the assumption that invasive species conserve their climatic niche in the invaded ranges. We test this assumption by analysing the climatic niche spaces of Spotted Knapweed in western North America and Europe. We show with robust cross-continental data that a shift of the observed climatic niche occurred between native and non-native ranges, providing the first empirical evidence that an invasive species can occupy climatically distinct niche spaces following its introduction into a new area. The models fail to predict the current invaded distribution, but correctly predict areas of introduction. Climate matching is thus a useful approach to identify areas at risk of introduction and establishment of newly or not-yet-introduced neophytes, but may not predict the full extent of invasions.

 

Keywords: Biological invasion • Centaurea maculosa • climate matching • niche conservatism • niche shift • niche-based models • Spotted Knapweed

1. Veratrum album (photo-copyright: Urs A. Treier)  

1. The importance of nitrogen and carbohydrate storage for plant growth of the alpine herb Veratrum album

Kleijn D, Treier UA & Müller-Schärer H

New Phytologist, 166(2): 565-575 (2005).

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We examined whether nitrogen (N) and carbohydrates reserves allow Veratrum album, an alpine forb, to start spring growth earlier than the neighbouring vegetation and to survive unpredictable disturbances resulting in loss of above-ground biomass.

 

Seasonal dynamics of plant reserves, soil N availability and vegetation growth were monitored. Veratrum album shoots were experimentally removed when carbohydrate reserves were at a seasonal minimum and the subsequent changes in biomass and reserves were compared with those in control plants.

 

Reserves did not give V. album a competitive advantage in spring; however, they did function as a buffer against the impact of calamities. Shoot removal resulted in significantly lower root dry weight, higher N concentration in rhizome and roots and lower starch concentrations in rhizome and roots but no plant mortality was observed.

 

Veratrum album used stored N reserves to supplement N uptake and establish high leaf N concentrations, which facilitated a rapid refilling of depleted carbohydrate reserves. The primary function of N reserves appears to be to allow V. album to complete the growing cycle in as short a period as possible, thus minimizing exposure to above-ground risks.

 

Keywords: carbohydrates • competition • defoliation • Liliaceae • nitrogen (N) • risk aversion • reserves • storage

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Other Publications

6. Arctic tundra in change (photo-copyright: Normand-Treier)  

6. Arctic tundra in change / Die arktische Tundra wandelt sich

Treier UA & Normand S
Kennzeichen DK, 2015, Nr. 104.

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Global change does not manifest itself everywhere to the same extend. In the arctic, temperatures rise faster than average which affects the occurrence and distribution of plants. Signe Normand and her team at Aarhus University, Denmark, aims at understanding the underlying processes.

 

Die globale Erwärmung manifestiert sich nicht überall gleich, in der Arktis wird es überdurchschnittlich wärmer. Das wirkt sich auf das Vorkommen und die Verbreitung der Pflanzen aus. Ein dänisches Forscherteam um Signe Normand von der Universität Aarhus untersucht die Zusammenhänge.

 

Keywords: arctic • climate change • shrub expansion • drone ecology • UAS • Greenland

5. Species list (graphics Urs A. Treier)  

5. Species list of the GEO-day of species’ diversity in the Sense-canyon, june 10th 2006 / Artenliste GEO-Tag der Artenvielfalt im Sensegraben, 10. Juni 2006

Verein O.S.K.A.R. & ÖkoBüro Jacques Studer

Made available online at Verein O.S.K.A.R., 2006.

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On the 9th and 10th of June 2006, 762 school children and 60 experts examined the „Sensegraben” (canyon of the Sense river, canton of Fribourg/Bern, Switzerland) within a 24 hours period (24 hour biodiversity blitz). It was possibly the largest field research campaign which took place in Switzerland. During this field campaign, 660 species where found, about 3 every minute. The present species list contains those 632 species, which have been determined unambiguously. The German GEO magazine reported on the highlights of the field campaign and the results were  summarised in a newspaper article (in German).

 

Am 9. und 10. Juni 2006 nahmen762 Schulkinder und 60 Experten den Sensegraben innerhalb 24 Stunden unter die Lupe. Es war wohl die grösste Feldforschungsaktion, die in der Schweiz je stattgefunden hat. Während der Feldarbeiten wurden 660 Arten gefunden, ca. 3 jede Minute. Die vorliegende Artenliste enthält diejenigen 632 Arten, welche zweifelsfrei bestimmt werden konnten. Das GEO Magazin berichtete über die Höhepunkte der Feldforschungsaktion und die Resultate wurden in einem Zeitungsartikel zusammengefasst.

 

Keywords: field study • biodiversity • nature • species diversity • 24 hour biodiversity blitz • BioBlitz • Switzerland • Sense river

4. Sense canyon (photo-copyright: Normand-Treier)  

4. Diverse and surprising discoveries / Vielfältige und überraschende Entdeckungen

Treier U

Freiburger Nachrichten, SA 30.09.06: 11 (2006). Newspaper Article (in German).

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Analysis of the „GEO-day“ of species’ diversity (BioBlitz): life in the nature paradise “Sensegraben”.

On the 9th and 10th of June 2006, 762 school children and 60 experts examined carefully the „Sensegraben” (canyon of the Sense river, canton of Fribourg/Bern, Switzerland); it was possibly the largest field research campaign that took place in Switzerland. At publishing time 650 species have been determined. After finishing the comprehensive determination work, 632 species have been named unambiguously. The highlights of the field campaign were  summarised in the German GEO magazine.

 

Auswertung des Geo-Tags der Artenvielfalt: das Leben im Naturparadies Sensegraben.

Am 9. und 10. Juni 2006 nahmen762 Schulkinder und 60 Experten den Sensegraben unter die Lupe; es war wohl die grösste Feldforschungsaktion, die in der Schweiz je stattgefunden hat. Zur Zeit der Veröffentlichung wurden 650 Arten bestimmt. Nach Beendigung der umfassenden Bestimmungsarbeiten konnten 632 Arten zweifelsfrei benannt werden. Das GEO Magazin berichtet über die Höhepunkte der Feldforschungsaktion.

 

Keywords: field study • biodiversity • nature • species diversity • 24 hour biodiversity blitz • BioBlitz • Geo magazine • Switzerland • Sense river

3. Plant determination (photo-copyright: Verein O.S.K.A.R.)  

3. Biodiversity / Biologische Vielfalt

Von Planta U & ÖkoBüro Jacques Studer

Made available online at Verein O.S.K.A.R., 2006.
Educational material / Unterrichtsmaterial (in German).

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The aim of the present educational material is, to sensibilise teacher and children for the significance of biodiversity and to enable insight into the immense richness of life-forms. The material should not only impart knowledge but also cause surprise and reflexion. At the same time, it should alert for the threats of biodiversity and motivate for its protection. The educational material is primarily directed at elementary schools and arranges in three parts: 1. background information, 2. supplementary information, and 3. educational aids.

 

Die vorliegende Unterrichtshilfe hat zum Ziel, Lehrpersonen und Kinder für die Bedeutung der biologischen Vielfalt zu sensibilisieren und ihnen einen Einblick in die unermessliche Vielfalt an Lebensformen zu ermöglichen. Sie soll nicht nur Wissen vermitteln, sondern auch zum Staunen und nachdenken anregen. Gleichzeitig soll sie auch auf die Bedrohungen der biologischen Vielfalt aufmerksam machen und zu ihrem Schutz motivieren. Diese Unterrichtshilfe richtet sich sowohl an die Primar- wie Orientierungsstufe und gliedert sich in drei Teile: 1. Hintergrundinformation, 2. Zusatzinformationen zum Vertiefen und 3. Unterrichtshilfen.

 

Keywords: biodiversity • nature • species diversity • threatened species • extinct species • ecosystem • floodplain

2. Computer work (graphics Urs A. Treier)  

2. Analysis Protocol for ABI GA 310 AFLP-runs

Treier UA

Made available online at University of Fribourg / Ecology & Evolution, 2004 (modified 2010).
Lab protocol.

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A lab protocol that provides a step-by-step guide to convert AFLP raw data, e.g. as generated by an ABI PRISM® 310 Genetic Analyzer, into a binary matrix by using the GelComparII™ software (version 3.5, Applied Maths). The proposed procedure allows an almost fully automated processing of ABI files.

 

Keywords: amplified fragment length polymorphism • automatic fragment scoring • raw data • molecular ecology • applied biosystems

1. Lab work (graphics Urs A. Treier)  

1. AFLP Protocol

Treier UA

Made available online at University of Fribourg / Ecology & Evolution, 2003 (modified 2010).
Lab protocol.

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A lab protocol that applies a multiplex PCR approach, a method that uses more than one labelled primer per PCR reaction (e.g. three). The proposed procedure increases efficiency, both concerning time and money, and was applied successfully for different species. The method was used in e.g. Handley et al. (2008) and Treier & Müller-Schärer (2011).

 

Keywords: amplified fragment length polymorphism • multiplex PCR • primer • molecular ecology • genetic analyzer • applied biosystems

My fascination for nature goes as far back as I can remember. What fascinated me was the different processes involved in growing plants rather than just learning the names given to them in our environment. I'm still very thankful to the occupational counselor who suggested high school and university rather than a gardening apprenticeship, although gardening and keeping some Bonsai trees still remain as some of my favourite hobbies alongside rock climbing and travelling. I studied Biology at the University of Fribourg, Switzerland, where I received a master's degree in Biology, specialising in Ecology and Evolution. In addition to my MSc degree in biology, I also completed courses in pedagogic and didactics to obtain an additional degree as a high school teacher (University of Fribourg/CH). Already during my studies I acquired working experience in fields outside academia, e.g. as collaborator and translator (Papiliorama/Nocturama, Switzerland) and Scientific employee (Nature and Landscape Conservation, State of Fribourg/CH; and Environmental consultants firm 'ÖkoBüro Jacques Studer', Fribourg/CH). However, science remained my primary interest, so I started a PhD project (University of Fribourg/CH, H. Müller-Schärer) and soon got involved in more exciting scientific projects and collaborations. My research carreer that started in Switzerland, guided me to the United States (University of Missouri-St. Louis, R. Ricklefs), Denmark (Aarhus University, J.C. Svenning), back to Switzerland (Swiss Federal Research Institute WSL, Christian Ginzler), and just recently again to Denmark (Aarhus University, S. Normand).

 

Urs A. Treier, field work in the Swiss Alps (Sangernboden, FR)enjoying field work in the Swiss Alps

Urs A. Treier, field work in Greenland (Nuuk Fjord, West GL)

and Greenland

Quadcopter mapping arctic vegetation, Sisimiut, Greenland 2015 (photo-copyright: Normand-Treier)

Our quadcopter is mapping arctic vegetation, Sisimiut, Greenland, July 2015.

Check out some images posted by the provider of our power supply system, which is based on renewable solar energy: SIStech 1, SIStech 2, SIStech 3

See our quadcopter in action published in the brochure for the cloud-based data platform ATLAS of MicaSense (download)