Logo: to the web site of Uppsala University

uu.sePublications from Uppsala University
Change search
Refine search result
1234567 1 - 50 of 822
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 1. Aarrestad, P. A.
    et al.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Masunga, G.
    Skarpe, C.
    Vegetation: Between Soils and Herbivores2014In: Elephants and Savanna Woodland Ecosystems: A Study from Chobe National Park, Botswana / [ed] Christina Skarpe, Johan T. du Toit and Stein R. Moe, Wiley-Blackwell, 2014, p. 61-88Chapter in book (Refereed)
    Abstract [en]

    The vegetation of the study area in Chobe National Park is influenced by a range of factors, including inundation by the Chobe River, soil moisture and fertility, and the impacts of different-size grazers and browsers. This chapter focuses on how the structure and species composition of the present vegetation in northern Chobe National Park is related to recent herbivory by elephants, as agents shaping the vegetation, and by mesoherbivores acting as controllers or responders, along with abiotic controllers such as soil type and distance to the river. In the study, a two-way indicator species analysis classified the vegetation data into four more or less distinct plant community groups (i) Baikiaea plurijuga-Combretum apiculatum woodland, (ii) Combretum mossambicense-Friesodielsia obovata wooded shrubland, (iii) Capparis tomentosa-Flueggea virosa shrubland and (iv) Cynodon dactylon-Heliotropium ovalifolium floodplain, named after the TWINSPAN indicator or preferential species with high cover, and the relative amount of shrubs and trees.

  • 2. Aarrestad, P. A.
    et al.
    Masunga, G. S.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Pitlagano, M. L.
    Marokane, W.
    Skarpe, C.
    Influence of soil, tree cover and large herbivores on field layer vegetation along a savanna landscape gradient in northern Botswana2011In: Journal of Arid Environments, ISSN 0140-1963, E-ISSN 1095-922X, Vol. 75, no 3, p. 290-297Article in journal (Refereed)
    Abstract [en]

    The response of the field layer vegetation to co-varying resource availability (soil nutrients, light) and resource loss (herbivory pressure) was investigated along a landscape gradient highly influenced by elephants and smaller ungulates at the Chobe River front in Botswana. TWINSPAN classification was used to identify plant communities. Detrended Correspondence Analysis (DCA) and Canonical Correspondence Analysis (CCA) were used to explore the vegetation-environment relationships. Four plant communities were described: Panicum maximum woodland, Tribulus terrestris woodland/shrubland, Chloris virgata shrubland and Cynodon dactylon floodplain. Plant height, species richness and diversity decreased with increasing resource availability and resource loss. The species composition was mainly explained by differences in soil resources, followed by variables related to light availability (woody cover) and herbivory, and by interactions between these variables. The vegetation structure and species richness, on the other hand, followed the general theories of vegetation responses to herbivory more closely than resource related theories. The results suggest a strong interaction between resource availability and herbivory in their influence on the composition, species richness and structure of the plant communities.

  • 3. Aguirre, A.
    et al.
    Vallejo-Marin, M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Piedra-Malagon, E. M.
    Cruz-Ortega, R.
    Dirzo, R.
    Morphological variation in the flowers of Jacaratia mexicana A. DC. (Caricaceae), a subdioecious tree2009In: Plant Biology, ISSN 1435-8603, E-ISSN 1438-8677, Vol. 11, no 3, p. 417-424Article in journal (Refereed)
    Abstract [en]

    The Caricaceae is a small family of tropical trees and herbs in which most species are dioecious. In the present study, we extend our previous work on dioecy in the Caricaceae, characterising the morphological variation in sexual expression in flowers of the dioecious tree Jacaratia mexicana. We found that, in J. mexicana, female plants produce only pistillate flowers, while male plants are sexually variable and can bear three different types of flowers: staminate, pistillate and perfect. To characterise the distinct types of flowers, we measured 26 morphological variables. Our results indicate that: (i) pistillate flowers from male trees carry healthy-looking ovules and are morphologically similar, although smaller than, pistillate flowers on female plants; (ii) staminate flowers have a rudimentary, non-functional pistil and are the only flowers capable of producing nectar; and (iii) perfect flowers produce healthy-looking ovules and pollen, but have smaller ovaries than pistillate flowers and fewer anthers than staminate flowers, and do not produce nectar. The restriction of sexual variation to male trees is consistent with the evolutionary path of dioecy from hermaphrodite ancestors through the initial invasion of male-sterile plants and a subsequent gradual reduction in female fertility in cosexual individuals (gynodioecy pathway), but further work is needed to confirm this hypothesis.

  • 4. Aguirre, A.
    et al.
    Vallejo-Marin, M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Salazar-Goroztieta, L.
    Arias, D. M.
    Dirzo, R.
    Variation in sexual expression in Jacaratia mexicana (Caricaceae) in southern Mexico: Frequency and relative seed performance of fruit-producing males2007In: Biotropica, ISSN 0006-3606, E-ISSN 1744-7429, Vol. 39, no 1, p. 79-86Article in journal (Refereed)
    Abstract [en]

    Dioecy, the segregation of male and female structures among individuals, is widespread in tropical plants, encompassing 10-30 percent of species in some sites. In many cases, interindividual sex separation is not complete, as individual plants, although nominally dioecious, may produce both types of reproductive structures. A common form of this sexual variation is the production of female structures in otherwise male individuals, commonly referred to as fruiting males. Here we report the existence of fruiting males in the dioecious tropical tree Jacaratia mexicana (Caricaceae). We show that fruiting males can constitute up to 45 percent of all males in some populations of a tropical forest in Southern Mexico. In order to determine the functional significance of fruiting males for the breeding system of J. mexicana, we compared the relative performance of male- and female-borne seeds. Our results show that seeds from fruiting males are three times less likely to germinate and survive than seeds from female trees. Based on relative seed fitness data, and sex ratios in natural populations, we estimate that 6-15 percent of the genes contributed by fruiting males to the next generation are transmitted via ovules, meaning that morphological variation in gender is at least partially accompanied by functional gender variation. Finally, our seed fitness estimates for fruiting males suggest that fruiting males will not replace female plants in natural populations.

  • 5.
    Aguirre-Gutierrez, Jesus
    et al.
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England.;Naturalis Biodivers Ctr, Biodivers Dynam, Leiden, Netherlands..
    Malhi, Yadvinder
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Lewis, Simon L.
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England.;UCL, Dept Geog, London, England..
    Fauset, Sophie
    Univ Plymouth, Sch Geog Earth & Environm Sci, Plymouth, Devon, England..
    Adu-Bredu, Stephen
    KNUST, CSIR Forestry Res Inst Ghana, Univ Post Off, Kumasi, Ghana..
    Affum-Baffoe, Kofi
    Forestry Commiss Ghana, Mensurat Unit, Kumasi, Ghana..
    Baker, Timothy R.
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England..
    Gvozdevaite, Agne
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Hubau, Wannes
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England.;Royal Museum Cent Africa, Serv Wood Biol, Tervuren, Belgium..
    Moore, Sam
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Peprah, Theresa
    KNUST, CSIR Forestry Res Inst Ghana, Univ Post Off, Kumasi, Ghana..
    Zieminska, Kasia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Arnold Arboretum Harvard Univ, Boston, MA 02115 USA..
    Phillips, Oliver L.
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England..
    Oliveras, Imma
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Long-term droughts may drive drier tropical forests towards increased functional, taxonomic and phylogenetic homogeneity2020In: Nature Communications, E-ISSN 2041-1723, Vol. 11, no 1Article in journal (Refereed)
    Abstract [en]

    Tropical ecosystems adapted to high water availability may be highly impacted by climatic changes that increase soil and atmospheric moisture deficits. Many tropical regions are experiencing significant changes in climatic conditions, which may induce strong shifts in taxonomic, functional and phylogenetic diversity of forest communities. However, it remains unclear if and to what extent tropical forests are shifting in these facets of diversity along climatic gradients in response to climate change. Here, we show that changes in climate affected all three facets of diversity in West Africa in recent decades. Taxonomic and functional diversity increased in wetter forests but tended to decrease in forests with drier climate. Phylogenetic diversity showed a large decrease along a wet-dry climatic gradient. Notably, we find that all three facets of diversity tended to be higher in wetter forests. Drier forests showed functional, taxonomic and phylogenetic homogenization. Understanding how different facets of diversity respond to a changing environment across climatic gradients is essential for effective long-term conservation of tropical forest ecosystems. Different aspects of biodiversity may not necessarily converge in their response to climate change. Here, the authors investigate 25-year shifts in taxonomic, functional and phylogenetic diversity of tropical forests along a spatial climate gradient in West Africa, showing that drier forests are less stable than wetter forests.

    Download full text (pdf)
    FULLTEXT01
  • 6.
    Ahmed, Engy
    et al.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Sci Life Lab, Tomtebodavagen 23A, SE-17165 Solna, Sweden..
    Parducci, Laura
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Unneberg, Per
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Cell and Molecular Biology, Molecular Evolution.
    Ågren, Rasmus
    Chalmers Univ Technol, Dept Chem & Biol Engn, Sci Life Lab, SE-41296 Gothenburg, Sweden..
    Schenk, Frederik
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Rattray, Jayne E.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Univ Calgary, Biol Sci, 2500 Univ Dr NW, Calgary, AB, Canada..
    Han, Lu
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics. Jilin Univ, Coll Life Sci, Ancient DNA Lab, Changchun, Jilin, Peoples R China..
    Muschitiello, Francesco
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden.;Columbia Univ, Lamont Doherty Earth Observ, 61 Route 9NW, Palisades, NY USA..
    Pedersen, Mikkel W.
    Univ Cambridge, Dept Zool, Downing St, Cambridge CB2 3EJ, England..
    Smittenberg, Rienk H.
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Yamoah, Kweku Afrifa
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Slotte, Tanja
    Stockholm Univ, Dept Ecol Environm & Plant Sci, SE-10691 Stockholm, Sweden.;Sci Life Lab, Tomtebodavagen 23A, SE-17165 Solna, Sweden..
    Wohlfarth, Barbara
    Stockholm Univ, Dept Geol Sci, SE-10691 Stockholm, Sweden.;Stockholm Univ, Bolin Ctr Climate Res, SE-10691 Stockholm, Sweden..
    Archaeal community changes in Lateglacial lake sediments: Evidence from ancient DNA2018In: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 181, p. 19-29Article in journal (Refereed)
    Abstract [en]

    The Lateglacial/early Holocene sediments from the ancient lake at Hasseldala Port, southern Sweden provide an important archive for the environmental and climatic shifts at the end of the last ice age and the transition into the present Interglacial. The existing multi-proxy data set highlights the complex interplay of physical and ecological changes in response to climatic shifts and lake status changes. Yet, it remains unclear how microorganisms, such as Archaea, which do not leave microscopic features in the sedimentary record, were affected by these climatic shifts. Here we present the metagenomic data set of Hasseldala Port with a special focus on the abundance and biodiversity of Archaea. This allows reconstructing for the first time the temporal succession of major Archaea groups between 13.9 and 10.8 ka BP by using ancient environmental DNA metagenomics and fossil archaeal cell membrane lipids. We then evaluate to which extent these findings reflect physical changes of the lake system, due to changes in lake-water summer temperature and seasonal lake-ice cover. We show that variations in archaeal composition and diversity were related to a variety of factors (e.g., changes in lake water temperature, duration of lake ice cover, rapid sediment infilling), which influenced bottom water conditions and the sediment-water interface. Methanogenic Archaea dominated during the Allerod and Younger Dryas pollen zones, when the ancient lake was likely stratified and anoxic for large parts of the year. The increase in archaeal diversity at the Younger Dryas/Holocene transition is explained by sediment infilling and formation of a mire/peatbog. (C) 2017 Elsevier Ltd. All rights reserved.

  • 7.
    Akiyama, Reiko
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Life History and Tolerance and Resistance against Herbivores in Natural Populations of Arabidopsis thaliana2011Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis, I combined observational studies with field and greenhouse experiments to examine selection on life history traits and variation in tolerance and resistance against herbivores in natural populations of the annual herb Arabidopsis thaliana in its native range. I investigated (1) phenotypic selection on flowering time and plant size, (2) the effects of timing of germination on plant fitness, (3) the effect of leaf damage on seed production, and (4) correlations between resistance against a specialist and a generalist insect herbivore.

    In all three study populations, flowering time was negatively related to plant fitness, but in only one of the populations, significant selection on flowering time was detected when controlling for size prior to the flowering season. The results show that correlations between flowering time and plant fecundity may be confounded by variation in plant size prior to the reproductive season.

    A field experiment detected conflicting selection on germination time: Early germination was associated with low seedling survival, but also with large leaf rosette before winter and high survival and fecundity among established plants. The results suggest that low survival among early germinating seeds is the main force opposing the evolution of earlier germination, and that the optimal timing of germination should vary in space and time as a function of the relative strength of selection acting during different life-history stages.

    Experimental leaf damage demonstrated that tolerance to damage was lowest among vegetative plants early in the season, and highest among flowering plants later in the season. Given similar damage levels, leaf herbivores feeding on plants before flowering should thus exert stronger selection on defence traits than those feeding on plants during flowering.

    Resistance against larval feeding by the specialist Plutella xylostella was negatively correlated with resistance against larval feeding by the generalist Mamestra brassicae and with resistance against oviposition by P. xylostella when variation in resistance was examined within and among two Swedish and two Italian A. thaliana populations. The results suggest that negative correlations between resistance against different herbivores and different life-history stages of herbivores may contribute to the maintenance of genetic variation in resistance.

    List of papers
    1. Selection on flowering time in three natural populations of Arabidopsis thaliana
    Open this publication in new window or tab >>Selection on flowering time in three natural populations of Arabidopsis thaliana
    (English)Manuscript (preprint) (Other academic)
    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159506 (URN)
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-03 Last updated: 2011-11-10
    2. Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana
    Open this publication in new window or tab >>Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana
    2014 (English)In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 27, no 1, p. 193-199Article in journal (Refereed) Published
    Abstract [en]

    The timing of germination is a key life-history trait that may strongly influence plant fitness and that sets the stage for selection on traits expressed later in the life cycle. In seasonal environments, the period favourable for germination and the total length of the growing season are limited. The optimal timing of germination may therefore be governed by conflicting selection through survival and fecundity. We conducted a field experiment to examine the effects of timing of germination on survival, fecundity and overall fitness in a natural population of the annual herb Arabidopsis thaliana in north-central Sweden. Seedlings were transplanted at three different times in late summer and in autumn covering the period of seed germination in the study population. Early germination was associated with low seedling survival, but also with high survival and fecundity among established plants. The advantages of germinating early more than balanced the disadvantage and selection favoured early germination. The results suggest that low survival among early germinating seeds is the main force opposing the evolution of earlier germination and that the optimal timing of germination should vary in space and time as a function of the direction and strength of selection acting during different life-history stages.

    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159664 (URN)10.1111/jeb.12293 (DOI)000329254500018 ()
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-06 Last updated: 2022-01-28Bibliographically approved
    3. Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)
    Open this publication in new window or tab >>Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)
    2012 (English)In: PLOS ONE, E-ISSN 1932-6203, Vol. 7, no 1, p. e30015-Article in journal (Refereed) Published
    Abstract [en]

    Background: The effect of herbivory on plant fitness varies widely. Understanding the causes of this variation is of considerable interest because of its implications for plant population dynamics and trait evolution. We experimentally defoliated the annual herb Arabidopsis thaliana in a natural population in Sweden to test the hypotheses that (a) plant fitness decreases with increasing damage, (b) tolerance to defoliation is lower before flowering than during flowering, and (c) defoliation before flowering reduces number of seeds more strongly than defoliation during flowering, but the opposite is true for effects on seed size.

    Methodology/Principal Findings: In a first experiment, between 0 and 75% of the leaf area was removed in May from plants that flowered or were about to start flowering. In a second experiment, 0, 25%, or 50% of the leaf area was removed from plants on one of two occasions, in mid April when plants were either in the vegetative rosette or bolting stage, or in mid May when plants were flowering. In the first experiment, seed production was negatively related to leaf area removed, and at the highest damage level, also mean seed size was reduced. In the second experiment, removal of 50% of the leaf area reduced seed production by 60% among plants defoliated early in the season at the vegetative rosettes, and by 22% among plants defoliated early in the season at the bolting stage, but did not reduce seed output of plants defoliated one month later. No seasonal shift in the effect of defoliation on seed size was detected.

    Conclusions/Significance: The results show that leaf damage may reduce the fitness of A. thaliana, and suggest that in this population leaf herbivores feeding on plants before flowering should exert stronger selection on defence traits than those feeding on plants during flowering, given similar damage levels.

    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159665 (URN)10.1371/journal.pone.0030015 (DOI)000301457200028 ()
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-06 Last updated: 2021-06-14Bibliographically approved
    4. Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thaliana
    Open this publication in new window or tab >>Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thaliana
    (English)Manuscript (preprint) (Other academic)
    National Category
    Ecology Evolutionary Biology Botany
    Research subject
    Biology with specialization in Ecological Botany
    Identifiers
    urn:nbn:se:uu:diva-159685 (URN)
    Funder
    Swedish Research Council
    Available from: 2011-10-06 Created: 2011-10-06 Last updated: 2011-11-10
    Download full text (pdf)
    fulltext
  • 8.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Noack, Sibylle
    Department of Zoology, Stockholm University.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thalianaManuscript (preprint) (Other academic)
  • 9.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana2014In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 27, no 1, p. 193-199Article in journal (Refereed)
    Abstract [en]

    The timing of germination is a key life-history trait that may strongly influence plant fitness and that sets the stage for selection on traits expressed later in the life cycle. In seasonal environments, the period favourable for germination and the total length of the growing season are limited. The optimal timing of germination may therefore be governed by conflicting selection through survival and fecundity. We conducted a field experiment to examine the effects of timing of germination on survival, fecundity and overall fitness in a natural population of the annual herb Arabidopsis thaliana in north-central Sweden. Seedlings were transplanted at three different times in late summer and in autumn covering the period of seed germination in the study population. Early germination was associated with low seedling survival, but also with high survival and fecundity among established plants. The advantages of germinating early more than balanced the disadvantage and selection favoured early germination. The results suggest that low survival among early germinating seeds is the main force opposing the evolution of earlier germination and that the optimal timing of germination should vary in space and time as a function of the direction and strength of selection acting during different life-history stages.

    Download full text (pdf)
    Akiyama & Ågren JEB 2014
  • 10.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)2012In: PLOS ONE, E-ISSN 1932-6203, Vol. 7, no 1, p. e30015-Article in journal (Refereed)
    Abstract [en]

    Background: The effect of herbivory on plant fitness varies widely. Understanding the causes of this variation is of considerable interest because of its implications for plant population dynamics and trait evolution. We experimentally defoliated the annual herb Arabidopsis thaliana in a natural population in Sweden to test the hypotheses that (a) plant fitness decreases with increasing damage, (b) tolerance to defoliation is lower before flowering than during flowering, and (c) defoliation before flowering reduces number of seeds more strongly than defoliation during flowering, but the opposite is true for effects on seed size.

    Methodology/Principal Findings: In a first experiment, between 0 and 75% of the leaf area was removed in May from plants that flowered or were about to start flowering. In a second experiment, 0, 25%, or 50% of the leaf area was removed from plants on one of two occasions, in mid April when plants were either in the vegetative rosette or bolting stage, or in mid May when plants were flowering. In the first experiment, seed production was negatively related to leaf area removed, and at the highest damage level, also mean seed size was reduced. In the second experiment, removal of 50% of the leaf area reduced seed production by 60% among plants defoliated early in the season at the vegetative rosettes, and by 22% among plants defoliated early in the season at the bolting stage, but did not reduce seed output of plants defoliated one month later. No seasonal shift in the effect of defoliation on seed size was detected.

    Conclusions/Significance: The results show that leaf damage may reduce the fitness of A. thaliana, and suggest that in this population leaf herbivores feeding on plants before flowering should exert stronger selection on defence traits than those feeding on plants during flowering, given similar damage levels.

    Download full text (pdf)
    fulltext
  • 11.
    Akiyama, Reiko
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Selection on flowering time in three natural populations of Arabidopsis thalianaManuscript (preprint) (Other academic)
  • 12.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Jaegerbrand, Annika K.
    Molau, Ulf
    Climate change and climatic events: community-, functional- and species-level responses of bryophytes and lichens to constant, stepwise, and pulse experimental warming in an alpine tundra2014In: Alpine Botany, ISSN 1664-2201, E-ISSN 1664-221X, Vol. 124, no 2, p. 81-91Article in journal (Refereed)
    Abstract [en]

    We experimentally imposed three different kinds of warming scenarios over 3 years on an alpine meadow community to identify the differential effects of climate warming and extreme climatic events on the abundance and biomass of bryophytes and lichens. Treatments consisted of (a) a constant level of warming with open top chambers (an average temperature increase of 1.87 A degrees C), (b) a yearly stepwise increase of warming (average temperature increases of 1.0; 1.87 and 3.54 A degrees C, consecutively), and (c) a pulse warming, i.e., a single first year pulse event of warming (average temperature increase of 3.54 A degrees C only during the first year). To our knowledge, this is the first climate change study that attempts to distinguish between the effects of constant, stepwise and pulse warming on bryophyte and lichen communities. We hypothesised that pulse warming would have a significant short-term effect compared to the other warming treatments, and that stepwise warming would have a significant mid-term effect compared to the other warming treatments. Acrocarpous bryophytes as a group increased in abundance and biomass to the short-term effect of pulse warming. We found no significant effects of mid-term (third-year) stepwise warming. However, one pleurocarpous bryophyte species, Tomentypnum nitens, generally increased in abundance during the warm year 1997 but decreased in control plots and in response to the stepwise warming treatment. Three years of experimental warming (all treatments as a group) did have a significant impact at the community level, yet changes in abundance did not translate into significant changes in the dominance hierarchies at the functional level (for acrocarpous bryophytes, pleurocarpous bryophytes, Sphagnum or lichens), or in significant changes in other bryophyte or lichen species. The results suggest that bryophytes and lichens, both at the functional group and species level, to a large extent are resistant to the different climate change warming simulations that were applied.

  • 13.
    Alatalo, Juha M
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Jägerbrand, Annika K.
    VTI, Swedish Natl Rd & Transport Res Inst, S-10215 Stockholm, Sweden..
    Molau, Ulf
    Univ Gothenburg, Dept Biol & Environm Sci, SE-40530 Gothenburg, Sweden..
    Testing reliability of short-term responses to predict longer-term responses of bryophytes and lichens to environmental change2015In: Ecological Indicators, ISSN 1470-160X, E-ISSN 1872-7034, Vol. 58, p. 77-85Article in journal (Refereed)
    Abstract [en]

    Environmental changes are predicted to have severe and rapid impacts on polar and alpine regions. At high latitudes/altitudes, cryptogams such as bryophytes and lichens are of great importance in terms of biomass, carbon/nutrient cycling, cover and ecosystem functioning. This seven-year factorial experiment examined the effects of fertilizing and experimental warming on bryophyte and lichen abundance in an alpine meadow and a heath community in subarctic Sweden. The aim was to determine whether shortterm responses (five years) are good predictors of longer-term responses (seven years). Fertilizing and warming had significant negative effects on total and relative abundance of bryophytes and lichens, with the largest and most rapid decline caused by fertilizing and combined fertilizing and warming. Bryophytes decreased most in the alpine meadow community, which was bryophyte-dominated, and lichens decreased most in the heath community, which was lichen-dominated. This was surprising, as the most diverse group in each community was expected to be most resistant to perturbation. Warming alone had a delayed negative impact. Of the 16 species included in statistical analyses, seven were significantly negatively affected. Overall, the impacts of simulated warming on bryophytes and lichens as a whole and on individual species differed in time and magnitude between treatments and plant communities (meadow and heath). This will likely cause changes in the dominance structures over time. These results underscore the importance of longer-term studies to improve the quality of data used in climate change models, as models based on short-term data are poor predictors of long-term responses of bryophytes and lichens.

  • 14.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Little, Chelsea J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Simulated global change: contrasting short and medium term growth and reproductive responses of a common alpine/Arctic cushion plant to experimental warming and nutrient enhancement2014In: SpringerPlus, E-ISSN 2193-1801, Vol. 3, article id 157Article in journal (Refereed)
    Abstract [en]

    Cushion plants are important components of alpine and Arctic plant communities around the world. They fulfill important roles as facilitators, nurse plants and foundation species across trophic levels for vascular plants, arthropods and soil microorganisms, the importance of these functions increasing with the relative severity of the environment. Here we report results from one of the few experimental studies simulating global change impacts on cushion plants; a factorial experiment with warming and nutrient enhancement that was applied to an alpine population of the common nurse plant, Silene acaulis, in sub-arctic Sweden. Experimental perturbations had significant short-term impacts on both stem elongation and leaf length. S. acaulis responded quickly by increasing stem elongation and (to a lesser extent) leaf length in the warming, nutrient, and the combined warming and nutrient enhancements. Cover and biomass also initially increased in response to the perturbations. However, after the initial positive short-term responses, S. acaulis cover declined in the manipulations, with the nutrient and combined warming and nutrient treatments having largest negative impact. No clear patterns were found for fruit production. Our results show that S. acaulis living in harsh environments has potential to react quickly when experiencing years with favorable conditions, and is more responsive to nutrient enhancement than to warming in terms of vegetative growth. While these conditions have an initial positive impact, populations experiencing longer-term increased nutrient levels will likely be negatively affected.

    Download full text (pdf)
    fulltext
  • 15.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Little, Chelsea J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Jagerbrand, Annika K.
    Molau, Ulf
    Dominance hierarchies, diversity and species richness of vascular plants in an alpine meadow: contrasting short and medium term responses to simulated global change2014In: PeerJ, E-ISSN 2167-8359, Vol. 2, p. e406-Article in journal (Refereed)
    Abstract [en]

    We studied the impact of simulated global change on a high alpine meadow plant community. Specifically, we examined whether short-term (5 years) responses are good predictors for medium-term (7 years) changes in the system by applying a factorial warming and nutrient manipulation to 20 plots in Latnjajaure, subarctic Sweden. Seven years of experimental warming and nutrient enhancement caused dramatic shifts in dominance hierarchies in response to the nutrient and the combined warming and nutrient enhancement treatments. Dominance hierarchies in the meadow moved from a community being dominated by cushion plants, deciduous, and evergreen shrubs to a community being dominated by grasses, sedges, and forbs. Short-termresponses were shown to be inconsistent in their ability to predict medium-term responses for most functional groups, however, grasses showed a consistent and very substantial increase in response to nutrient addition over the seven years. The non-linear responses over time point out the importance of longer-term studies with repeated measurements to be able to better predict future changes. Forecasted changes to temperature and nutrient availability have implications for trophic interactions, and may ultimately influence the access to and palatability of the forage for grazers. Depending on what anthropogenic change will be most pronounced in the future (increase in nutrient deposits, warming, or a combination of them both), different shifts in community dominance hierarchies may occur. Generally, this study supports the productivity-diversity relationship found across arctic habitats, with community diversity peaking in mid-productivity systems and degrading as nutrient availability increases further. This is likely due the increasing competition in plant-plant interactions and the shifting dominance structure with grasses taking over the experimental plots, suggesting that global change could have high costs to biodiversity in the Arctic.

    Download full text (pdf)
    fulltext
  • 16.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Little, Chelsea J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Jagerbrand, Annika K.
    Molau, Ulf
    Vascular plant abundance and diversity in an alpine heath under observed and simulated global change2015In: Scientific Reports, E-ISSN 2045-2322, Vol. 5, article id 10197Article in journal (Refereed)
    Abstract [en]

    Global change is predicted to cause shifts in species distributions and biodiversity in arctic tundra. We applied factorial warming and nutrient manipulation to a nutrient and species poor alpine/arctic heath community for seven years. Vascular plant abundance in control plots increased by 31%. There were also notable changes in cover in the nutrient and combined nutrient and warming treatments, with deciduous and evergreen shrubs declining, grasses overgrowing these plots. Sedge abundance initially increased significantly with nutrient amendment and then declined, going below initial values in the combined nutrient and warming treatment. Nutrient addition resulted in a change in dominance hierarchy from deciduous shrubs to grasses. We found significant declines in vascular plant diversity and evenness in the warming treatment and a decline in diversity in the combined warming and nutrient addition treatment, while nutrient addition caused a decline in species richness. The results give some experimental support that species poor plant communities with low diversity may be more vulnerable to loss of species diversity than communities with higher initial diversity. The projected increase in nutrient deposition and warming may therefore have negative impacts on ecosystem processes, functioning and services due to loss of species diversity in an already impoverished environment.

    Download full text (pdf)
    fulltext
  • 17.
    Alatalo, Juha M.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ostapenko, Oksana V.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    The Swedish system: The image cracking when taking a closer look2014In: Geoforum, ISSN 0016-7185, E-ISSN 1872-9398, Vol. 53, p. 82-83Article, review/survey (Refereed)
    Abstract [en]

    Sweden has a high international profile regarding social issues and projects an image as one of the best countries in the world in terms of social indicators. Here we argue for a revised view as the reality is that Swedish system is very segregated, particularly in terms of (1) relative lack of women in positions of high influence, (2) it is the worst country in the EU28 regarding long-term unemployment for people born outside the country, and (3) it has a education system that after a number of reforms is involved in a "race towards the bottom" to profit from students. At the same time Sweden undervalues foreign academic qualifications and getting work largely depends on "who you know", not "what you know".

  • 18. Alberts, Susan C.
    et al.
    Altmann, Jeanne
    Brockman, Diane K.
    Cords, Marina
    Fedigan, Linda M.
    Pusey, Anne
    Stoinski, Tara S.
    Strier, Karen B.
    Morris, William F.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Bronikowski, Anne M.
    Reproductive aging patterns in primates reveal that humans are distinct2013In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 110, no 33, p. 13440-13445Article in journal (Refereed)
    Abstract [en]

    Women rarely give birth after similar to 45 y of age, and they experience the cessation of reproductive cycles, menopause, at similar to 50 y of age after a fertility decline lasting almost two decades. Such reproductive senescence in mid-lifespan is an evolutionary puzzle of enduring interest because it should be inherently disadvantageous. Furthermore, comparative data on reproductive senescence from other primates, or indeed other mammals, remains relatively rare. Here we carried out a unique detailed comparative study of reproductive senescence in seven species of nonhuman primates in natural populations, using long-term, individual-based data, and compared them to a population of humans experiencing natural fertility and mortality. In four of seven primate species we found that reproductive senescence occurred before death only in a small minority of individuals. In three primate species we found evidence of reproductive senescence that accelerated throughout adulthood; however, its initial rate was much lower than mortality, so that relatively few individuals experienced reproductive senescence before death. In contrast, the human population showed the predicted and well-known pattern in which reproductive senescence occurred before death for many women and its rate accelerated throughout adulthood. These results provide strong support for the hypothesis that reproductive senescence in midlife, although apparent in natural-fertility, natural-mortality populations of humans, is generally absent in other primates living in such populations.

  • 19.
    Alessi, Nicola
    et al.
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bozen Bolzano, Italy.
    Tesitel, Jakub
    Masaryk Univ, Dept Bot, Brno, Czech Republic.
    Zerbe, Stefan
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bozen Bolzano, Italy.
    Spada, Francesco
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Sapienza Univ Roma, Dept Environm Biol, Rome, Italy.
    Agrillo, Emiliano
    Sapienza Univ Roma, Dept Environm Biol, Rome, Italy.
    Wellstein, Camilla
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bozen Bolzano, Italy.
    Ancient refugia and present-day habitat suitability of native laurophylls in Italy2019In: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 30, no 3, p. 564-574Article in journal (Refereed)
    Abstract [en]

    Questions European native laurophyllous species are interesting for their biogeography and evolutionary history, as well as for their responses to global changes. We identified Italian native laurophylls on the basis of morphology, biogeographical history and ecological niche to study whether these species are in equilibrium with the present-day climate. Furthermore, we localized Quaternary refugia and areas of potential spread of native laurophylls using distribution patterns of realized and potential aggregations of native laurophylls, respectively. Location Italy. Methods We extracted data for 17 087 forest plots from a phytosociological database. Detrended Correspondence Analysis of these plots with overlay of climatic and environmental variables was performed to identify native laurophylls, i.e., evergreen broad-leaved species of late Tertiary radiation, occupying a warm and humid niche. Potential ranges of laurophylls were calculated using Beals' index of sociological favourability. The realized/potential range-size ratio was calculated for each single laurophyll to understand whether it is in equilibrium with the present-day climate. Distribution patterns of realized and potential aggregations of laurophylls were mapped. Results Ordination analysis provided a selection of 11 species as Italian native laurophylls. Most of them occupied less than half of their estimated potential range. Realized aggregations richest in native laurophylls were localized in the central Apennines. However, the Italian forests showed high potential for native laurophylls with the richest potential aggregations in the whole Apennines and in the southern Alps. Conclusions Most of the Italian native laurophylls showed non-equilibrium with the current climate, suggesting that late-Quaternary events could better explain their present-day distribution than on-going climate change. Furthermore, their refugia in central Italy suggest the persistence in sites with temperate climate during Quaternary environmental changes. The high suitability of Italian forests for laurophylls, along with global changes, suggests possible future spreading of these species.

  • 20.
    Alessi, Nicola
    et al.
    Free Univ Bozen Bolzano, Fac Sci & Technol, Pzza Univ 5, I-39100 Bozen Bolzano, Italy.
    Wellstein, Camilla
    Free Univ Bozen Bolzano, Fac Sci & Technol, Pzza Univ 5, I-39100 Bozen Bolzano, Italy.
    Spada, Francesco
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Sapienza Univ Roma, Dept Environm Biol, Lgo Cristina di Svezia 24, I-00165 Rome.
    Zerbe, Stefan
    Free Univ Bozen Bolzano, Fac Sci & Technol, Pzza Univ 5, I-39100 Bozen Bolzano, Italy.
    Phytocoenological approach to the ecology of Laurus nobilis L. in Italy2018In: Rendiconti Lincei SCIENZE FISICHE E NATURALI, ISSN 2037-4631, E-ISSN 1720-0776, Vol. 29, no 2, p. 343-354Article in journal (Refereed)
    Abstract [en]

    Laurus nobilis L. (Laurel) is considered one of the most emblematic epigones of the late-Tertiary laurophyllous biome, persisting within the Mediterranean vegetation. Describing its present ecology and coenology is crucial to understand its biogeographical history as well as to develop consistent conservation and management practices in the context of the European Habitat Directive. We used recently available vegetation and environmental databases to investigate the coenological amplitude of Laurus in Italy, and to elucidate significant aspects of its persistence in the country. The coenological amplitude was assessed using the clustering method. Ordination techniques and regression trees were used to understand which environmental factors influence, respectively, the occurrence and the abundance of the species and, therefore, characterize its niche. Our results show a wide coenological amplitude of Laurus with respect to other laurophyllous species, growing within a wide range of forest communities. While the occurrence of the species is limited by winter temperature and favored by precipitation seasonality, changes in its abundance show a more refined pattern. In this latter case, two main groups of Laurus populations were differentiated based on water availability. The first group depends on abundant precipitations during the year while the second one buffers the summer aridity with soils rich in nutrients and moisture. Our findings provide crucial knowledge on Laurus habitats in Italy. However, discrepancies between our results and guidelines of the European Habitat Directive arose. The results presented here allow scientifically sound procedures for the regional conservation and management program.

  • 21.
    Alessi, Nicola
    et al.
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bolzano, Italy.;Univ Bologna, Dept Biol Geol & Environm Sci, Geol & Environm Sci, Biodivers & Macroecol Grp,Alma Mater Studiorum, Via Irnerio 42, I-40126 Bologna, Italy..
    Wellstein, Camilla
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bolzano, Italy..
    Spada, Francesco
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Zerbe, Stefan
    Free Univ Bozen Bolzano, Fac Sci & Technol, Bolzano, Italy..
    Population structure of Laurus nobilis L. in Central Italian forests: evidence for its ongoing expansion2021In: Rendiconti Lincei SCIENZE FISICHE E NATURALI, ISSN 2037-4631, E-ISSN 1720-0776, Vol. 32, p. 365-376Article in journal (Refereed)
    Abstract [en]

    During the last decades, an ongoing spread of broad-leaved evergreen laurophyllous species has been reported for forests of Southern Europe. Several factors were suggested as the main drivers of the phenomenon, namely global warming, land-use change, evolutionary history, and increase in atmospheric CO2. Among laurophylls, Laurus nobilis L. is considered one of the most prominent from the morphological, evolutionary, and ecological point of view. We studied the population structure of L. nobilis in Central Italy in its natural habitat to investigate its regeneration and potential expansion along with the influence biotic and abiotic factors. To define types of population structures, we collected proportions of six growth classes of L. nobilis in 16 sites. We obtained three types of population structure, i.e., (1) stable, (2) dynamic, and (3) regressive. The first two types are the most frequent, suggesting a potential increase of L. nobilis abundance within forests of Central Italy. The regressive population type occurs mainly in sites with heavy ungulate impact. High propagule pressure along with shaded and moist environmental conditions favor L. nobilis regeneration. Accordingly, we found evidence of a recent L. nobilis spread in Central Italian forests. We suggest the increase of forest cover and age, due to the abandonment of traditional rural practices, as key factors for the regeneration of this apparently late-successional laurophyll. In conclusion, the recent expansion of L. nobilis that we observed in the Italian forest stands can therefore be ascribed to a process of natural recover of a potential niche following land-use change.

    Download full text (pdf)
    FULLTEXT01
  • 22.
    Ament-Velásquez, S. Lorena
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology. Stockholm University.
    Vogan, Aaron A.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Granger-Farbos, Alexandra
    Institut de Biochimie et de Génétique Cellulaire, UMR 5095 CNRS, Université de Bordeaux, France.
    Bastiaans, Eric
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology. Laboratory of Genetics, Wageningen University & Research, Droeven-daalsesteeg 1, Wageningen, The Netherlands.
    Martinossi-Allibert, Ivain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology. Norwegian University of Science and Technology.
    Saupe, Sven J.
    Institut de Biochimie et de Génétique Cellulaire, UMR 5095 CNRS, Université de Bordeaux, France.
    de Groot, Suzette
    Laboratory of Genetics, Wageningen University & Research, Droeven-daalsesteeg 1, Wageningen, The Netherlands.
    Lascoux, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Debets, Alfons J. M.
    Laboratory of Genetics, Wageningen University & Research, Droeven-daalsesteeg 1, Wageningen, The Netherlands.
    Clavé, Corinne
    Institut de Biochimie et de Génétique Cellulaire, UMR 5095 CNRS, Uni-versité de Bordeaux, France.
    Johannesson, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology.
    Allorecognition genes drive reproductive isolation in Podospora anserina2022In: Nature Ecology & Evolution, E-ISSN 2397-334X, Vol. 6, no 7, p. 910-923Article in journal (Refereed)
    Abstract [en]

    Allorecognition, the capacity to discriminate self from conspecific non-self, is a ubiquitous organismal feature typically governed by genes evolving under balancing selection. Here, we show that in the fungus Podospora anserina, allorecognition loci controlling vegetative incompatibility (het genes), define two reproductively isolated groups through pleiotropic effects on sexual compatibility. These two groups emerge from the antagonistic interactions of the unlinked loci het-r (encoding a NOD-like receptor) and het-v (encoding a methyltransferase and an MLKL/HeLo domain protein). Using a combination of genetic and ecological data, supported by simulations, we provide a concrete and molecularly defined example whereby the origin and coexistence of reproductively isolated groups in sympatry is driven by pleiotropic genes under balancing selection.

    Download full text (pdf)
    fulltext
  • 23. Amer, M.
    et al.
    Tyler, A.
    Fouda, T.
    Hunter, P.
    Elmetwalli, A.
    Wilson, C.
    Vallejo-Marin, M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Spectral characteristics for estimation heavy metals accumulation in wheat plants and grain2017In: Scientific Papers-Series Management Economic Engineering in Agriculture and Rural Development, Vol. 17, no 3, p. 47-55Article in journal (Refereed)
    Abstract [en]

    Plants would the start with step of a metal's pathway starting with the dirt on heterotrophic creatures for example, such that animals and humans, thus the substance from claiming metallic follow components for eatable parts of a plant representable accessible load of these metals that might enter those natural way of life through plants. Around metal elements, Cu and Zn would micro nutrients as they are essential in trace concentrations for physiological processes in plants. Furthermore consequently would a critical part from the soil-plant-food continuum. Therefor this study aimed to analysing the performance of multivariate hyperspectral vegetation indices of wheat (Triticum aestivum L.) in estimating the accumulation of these elements in plant dry mutter and the final product of Egyptian wheat crop irrigated with high concentrations of Zn and Cu. We applied five concentrations for each element (0.05, 20, 40, 100, and 150 ppm of Zn) and (0.02, 8, 10, 12, and 15 ppm of Cu) to a controlled greenhouse experiment to examine the effect of these concentrations on plant spectral characteristics and study the possibility of using spectroradiometry measurements for identifying the grain content of these metals. The results demonstrated that The hyperspectral vegetation indices had a potential for monitoring Zn concentration in the plant dry matter. NPCI and PSSR had a highest correlation with Cu phytoaccumulation into the grains with highest significant level (P-Value < 0.01) and (r) values (-0.39, -0.42).

  • 24.
    Anderson, Bruce
    et al.
    Department of Botany & Zoology, Stellenbosch Univ., Cape Town, South Africa..
    Pannell, John
    Department of Ecology and Evolution, University of Lausanne, 1015 Lausanne, Switzerland..
    Billiard, Sylvain
    University Lille, CNRS, UMR 8198 – Evo-Eco-Paleo, 59000 Lille, France..
    Burgarella, Concetta
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Evolutionary Biology.
    de Boer, Hugo
    Natural History Museum, University of Oslo, 0318 Oslo, Norway..
    Dufay, Mathilde
    CEFE, University Montpellier, CNRS, University Paul Valéry Montpellier 3, Ephe, IRD, Montpellier, France..
    Helmstetter, Andrew J.
    FRB – CESAB, 5 Rue de l’École de Médecine, 34000 Montpellier, France..
    Méndez, Marcos
    Area of Biodiversity and Conservation, Universidad Rey Juan Carlos, Madrid, Spain..
    Otto, Sarah P.
    Department of Zoology, University of British Columbia, Vancouver, BC, Canada.
    Roze, Denis
    IRL 3614, CNRS, Sorbonne Université, Station Biologique de Roscoff, 29688 Roscoff Cedex, France..
    Sauquet, Hervé
    National Herbarium of New South Wales, Royal Botanic Gardens and Domain Trust, Sydney, NSW 2000, Australia.;Evolution and Ecology Research Centre, School of Biological, Earth and Environmental Sciences, University of New South Wales, Sydney, NSW, Australia..
    Schoen, Daniel
    Department of Biology, McGill University, Montreal, QC, Canada..
    Schönenberger, Jürg
    Department of Botany and Biodiversity Research, University of Vienna, Rennweg 14, 1030 Vienna, Austria..
    Vallejo‐Marín, Mario
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Zenil-Ferguson, Rosana
    Department of Biology, University of Kentucky, Lexington, KY 40506-0225, USA..
    Käfer, Jos
    Université de Lyon, Université Lyon 1, CNRS, Laboratoire de Biométrie et Biologie Evolutive UMR 5558, 69622 Villeurbanne, France..
    Glemin, Sylvain
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. CNRS, Ecosystèmes Biodiversité Evolution (Université de Rennes), 35000 Rennes, France.
    Opposing effects of plant traits on diversification2023In: iScience, E-ISSN 2589-0042, Vol. 26, no 4, article id 106362Article in journal (Refereed)
    Abstract [en]

    Species diversity can vary dramatically across lineages due to differences in speciation and extinction rates. Here, we explore the effects of several plant traits on diversification, finding that most traits have opposing effects on diversification. For example, outcrossing may increase the efficacy of selection and adaptation but also decrease mate availability, two processes with contrasting effects on lineage persistence. Such opposing trait effects can manifest as differences in diversification rates that depend on ecological context, spatiotemporal scale, and associations with other traits. The complexity of pathways linking traits to diversification suggests that the mechanistic underpinnings behind their correlations may be difficult to interpret with any certainty, and context dependence means that the effects of specific traits on diversification are likely to differ across multiple lineages and timescales. This calls for taxonomically and context-controlled approaches to studies that correlate traits and diversification.

    Download full text (pdf)
    fulltext
  • 25.
    Angert, Amy L.
    et al.
    Univ British Columbia, Dept Bot & Zool, Vancouver, BC V6T 1Z4, Canada..
    Bontrager, Megan G.
    Univ Calif Davis, Dept Ecol & Evolut, Davis, CA 95616 USA..
    Ågren, Jon
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    What Do We Really Know About Adaptation at Range Edges?2020In: ANNUAL REVIEW OF ECOLOGY, EVOLUTION, AND SYSTEMATICS, VOL 51, 2020 / [ed] Futuyma, D J, PALO ALTO USA: ANNUAL REVIEWS, 2020, p. 341-361Chapter in book (Refereed)
    Abstract [en]

    Recent theory and empirical evidence have provided new insights regarding how evolutionary forces interact to shape adaptation at stable and transient range margins. Predictions regarding trait divergence at leading edges are frequently supported. However, declines in fitness at and beyond edges show that trait divergence has sometimes been insufficient to maintain high fitness, so identifying constraints to adaptation at range edges remains a key challenge. Indirect evidence suggests that range expansion may be limited by adaptive genetic variation, but direct estimates of genetic constraints at and beyond range edges are still scarce. Sequence data suggest increased genetic load in edge populations in several systems, but its causes and fitness consequences are usually poorly understood. The balance between maladaptive and positive effects of gene flow on fitness at range edges deserves further study. It is becoming increasingly clear that characterizations about degree of adaptation based solely on geographical peripherality are unsupported.

  • 26.
    Apuli, Rami-Petteri
    et al.
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala BioCtr, Dept Plant Biol, Uppsala, Sweden..
    Richards, Thomas J.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala BioCtr, Dept Plant Biol, Uppsala, Sweden..
    Rendon-Anaya, Martha
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala BioCtr, Dept Plant Biol, Uppsala, Sweden..
    Karacic, Almir
    Swedish Univ Agr Sci, Inst Crop Prod Ecol, Uppsala, Sweden..
    Rönnberg-Wästljung, Ann-Christin
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala BioCtr, Dept Plant Biol, Uppsala, Sweden..
    Ingvarsson, Pär K.
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala BioCtr, Dept Plant Biol, Uppsala, Sweden..
    The genetic basis of adaptation in phenology in an introduced population of Black Cottonwood (Populus trichocarpa, Torr. & Gray)2021In: BMC Plant Biology, E-ISSN 1471-2229, Vol. 21, article id 317Article in journal (Refereed)
    Abstract [en]

    Background: Entering and exiting winter dormancy present important trade-offs between growth and survival at northern latitudes. Many forest trees display local adaptation across latitude in traits associated with these phenology transitions. Transfers of a species outside its native range introduce the species to novel combinations of environmental conditions potentially requiring different combinations of alleles to optimize growth and survival. In this study, we performed genome wide association analyses and a selection scan in a P. trichocarpa mapping population derived from crossings between clones collected across the native range and introduced into Sweden. GWAS analyses were performed using phenotypic data collected across two field seasons and in a controlled phytotron experiment.

    Results: We uncovered 584 putative candidate genes associated with spring and autumn phenology traits as well as with growth. Many regions harboring variation significantly associated with the initiation of leaf shed and leaf autumn coloring appeared to have been evolving under positive selection in the native environments of P. trichocarpa. A comparison between the candidate genes identified with results from earlier GWAS analyses performed in the native environment found a smaller overlap for spring phenology traits than for autumn phenology traits, aligning well with earlier observations that spring phenology transitions have a more complex genetic basis than autumn phenology transitions.

    Conclusions: In a small and structured introduced population of P. trichocarpa, we find complex genetic architectures underlying all phenology and growth traits, and identify multiple putative candidate genes despite the limitations of the study population.

    Download full text (pdf)
    FULLTEXT01
  • 27. Arkani, Samara
    et al.
    Cao, Jia
    Lundin, Johanna
    Nilsson, Daniel
    Källman, Thomas
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Medical Biochemistry and Microbiology.
    Barker, Gillian
    Holmdahl, Gundela
    Clementsson Kockum, Christina
    Matsson, Hans
    Nordenskjöld, Agneta
    Evaluation of the ISL1 gene in the pathogenesis of bladder exstrophy in a Swedish cohort2018In: Human genome variation, ISSN 2054-345X, Vol. 5, no 1, article id 18009Article in journal (Refereed)
    Abstract [en]

    Bladder exstrophy is a congenital closure defect of the urinary bladder with a profound effect on morbidity. Although the malformation is usually sporadic, a genetic background is supported by an increased recurrence risk in relatives, higher concordance rates in monozygotic twins and several associated chromosomal aberrations. Recently, the ISL1 gene was presented as a candidate gene for bladder exstrophy and epispadias complex (BEEC) development in two different studies. In our study, we screened for genetic variants in the ISL1 gene in DNA from 125 Swedish patients using Sanger sequencing and array-CGH analysis. In addition, we evaluated ISL1 expression in RNA of human bladder during embryonic and fetal weeks 5–10 relative to that in lung tissue (week 9). In total, 21 single-nucleotide variants were identified, including a potentially novel missense variant, c.137C>G p.(Ala46Gly), substituting a conserved amino acid. This variant was inherited from an unaffected mother. No structural variants were identified. RNA sequencing revealed ISL1 mRNA expression during the critical time frame of human bladder development. In conclusion, we did not detect any known or likely pathogenic variants in the ISL1 gene in 125 Swedish BEEC patients, indicating that variation in the ISL1 gene is not a common genetic mechanism of BEEC development in the Swedish population.

    Download full text (pdf)
    fulltext
  • 28. Armbruster, W. Scott
    et al.
    Hansen, Thomas F.
    Pélabon, Christophe
    Pérez-Barrales, Rocio
    Maad, Johanne
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    The adaptive accuracy of flowers: measurement and microevolutionary patterns2009In: Annals of Botany, ISSN 0305-7364, E-ISSN 1095-8290, Vol. 103, no 9, p. 1529-1545Article in journal (Refereed)
  • 29.
    Asplund, Linnea
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Evolution.
    Hagenblad, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Leino, Matti W.
    Re-evaluating the history of the wheat domestication gene NAM-B1 using historical plant material2010In: Journal of Archaeological Science, ISSN 0305-4403, E-ISSN 1095-9238, Vol. 37, no 9, p. 2303-2307Article in journal (Refereed)
    Abstract [en]

    The development of agriculture is closely associated with the domestication of wheat, one of the earliest crop species. During domestication key genes underlying traits important to Neolithic agriculture were targeted by selection. One gene believed to be such a domestication gene is NAM-B1, affecting both nutritional quality and yield but with opposite effects. A null mutation, first arisen in emmer wheat, decreases the nutritional quality but delays maturity and increases grain size; previously the ancestral allele was believed lost during the domestication of durum and bread wheat by indirect selection for larger grain. By genotyping 63 historical seed samples originating from the 1862 International Exhibition in London, we found that the ancestral allele was present in two spelt wheat and two bread wheat cultivars widely cultivated at the time. This suggests that fixation of the mutated allele of NAM-B1 in bread wheat, if at all, occurred during modern crop improvement rather than during domestication. We also discuss the value of using archaeological and historical plant material to further the understanding of the development of agriculture.

  • 30.
    Asplund, Linnea
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Leino, Matti W.
    Hagenblad, Jenny
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Allelic Variation at the Rht8 Locus in a 19th Century Wheat Collection2012In: Scientific World Journal, E-ISSN 1537-744X, p. 385610-Article in journal (Refereed)
    Abstract [en]

    Wheat breeding during the 20th century has put large efforts into reducing straw length and increasing harvest index. In the 1920s an allele of Rht8 with dwarfing effects, found in the Japanese cultivar "Akakomugi," was bred into European cultivars and subsequently spread over the world. Rht8 has not been cloned, but the microsatellite marker WMS261 has been shown to be closely linked to it and is commonly used for genotyping Rht8. The "Akakomugi" allele is strongly associated with WMS261-192bp. Numerous screens of wheat cultivars with different geographical origin have been performed to study the spread and influence of the WMS261-192bp during 20th century plant breeding. However, the allelic diversity of WMS261 in wheat cultivars before modern plant breeding and introduction of the Japanese dwarfing genes is largely unknown. Here, we report a study of WMS261 allelic diversity in a historical wheat collection from 1865 representing worldwide major wheats at the time. The majority carried the previously reported 164 bp or 174 bp allele, but with little geographical correlation. In a few lines, a rare 182 bp fragment was found. Although straw length was recognized as an important character already in the 19th century, Rht8 probably played a minor role for height variation. The use of WMS261 and other functional markers for analyses of historical specimens and characterization of historic crop traits is discussed.

  • 31. Avia, Komlan
    et al.
    Karkkainen, Katri
    Lagercrantz, Ulf
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Savolainen, Outi
    Association of FLOWERING LOCUS T/TERMINAL FLOWER 1-like gene FTL2 expression with growth rhythm in Scots pine (Pinus sylvestris)2014In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 204, no 1, p. 159-170Article in journal (Refereed)
    Abstract [en]

    Understanding the genetic basis of the timing of bud set, an important trait in conifers, is relevant for adaptation and forestry practice. In common garden experiments, both Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) show a latitudinal cline in the trait. We compared the regulation of their bud set biology by examining the expression of PsFTL2, a Pinus sylvestris homolog to PaFTL2, a FLOWERING LOCUS T/TERMINAL FLOWER 1 (FT/TFL1)-like gene, the expression levels of which have been found previously to be associated with the timing of bud set in Norway spruce. In a common garden study, we analyzed the relationship of bud phenology under natural and artificial photoperiods and the expression of PsFTL2 in a set of Scots pine populations from different latitudes. The expression of PsFTL2 increased in the needles preceding bud set and decreased during bud burst. In the northernmost population, even short night periods were efficient to trigger this expression, which also increased earlier under all photoperiodic regimes compared with the southern populations. Despite the different biology, with few limitations, the two conifers that diverged 140 million yr ago probably share an association of FTL2 with bud set, pointing to a common mechanism for the timing of growth cessation in conifers.

  • 32.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Det är långt mer än doften som gör skvattram unik2022In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 116, no 1, p. 22-31Article in journal (Refereed)
  • 33.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Dynamik och evolution på de östafrikanska bergen2017In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 111, no 5, p. 228-239Article in journal (Refereed)
    Abstract [en]

    A brief overview of the conspicuous alpine flora and vegetation of the East African mountains is presented. 

  • 34.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ett etnobotaniskt livsverk2015In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 109, no 6, p. 346-347Article in journal (Refereed)
    Abstract [sv]

    Vagn J. Brøndegaard skrev mer än 1600 artiklar om allt som hade med relationen mellan växter och människor att göra. Många av dessa har nu ställts samman i två vackra volymer.

  • 35.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Gunnar Björkman och hans expedition till Lule lappmark 1924: Gunnar Björkman’s expedition to Swedish Lapland in 19242013In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 107, no 6, p. 354-358Article in journal (Other academic)
    Abstract [en]

    Drawings by Torsten Höjer from Gunnar Björkman's botanical expedition to Swedish Lapland in 1924 are presented with some biographical notes on Björkman. The paleontologist  Birger Bohlin also participated.

  • 36.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Mossflora över Sankta Helena2013In: Myrinia, ISSN 1102-4194, Vol. 23, p. 84-87Article in journal (Other academic)
    Abstract [en]

    A new bryophyte flora of St. Helena in the South Atlantic is presented. Of the known 110 species, 26 are (as presently known) endemic.

  • 37.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre.
    Om São Tomé, begonior och öar i havet2018In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 112, no 1, p. 32-40Article in journal (Refereed)
    Abstract [en]

    A brief overview of the vegetation of São Tomë and Príncipe is presented. The several endemic and large species of Begonia on the islands are discussed in more detail.

  • 38.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Sankta Helena: en hotad endemisk flora. 1. Den ursprungliga floran och vegetationen och den historiska utvecklingen2014In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, no 3-4, p. 206-218Article in journal (Other academic)
    Abstract [en]

    An overview of the endemic flora and the original vegetation of Saint Helena is given.

  • 39.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Sankta Helena: en hotad endemisk flora. 2. situationen i dag2014In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, no 5, p. 232-244Article in journal (Refereed)
    Abstract [en]

    The present-day situation for the endemic flora of Saint Helena is described.

  • 40.
    Backéus, Ingvar
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Växterna på Indiska oceanens öar kom över havet.2020In: Fauna & flora: en spegling av svensk natur, E-ISSN 0014-8903, Vol. 115, no 3, p. 34-48Article in journal (Refereed)
  • 41.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre. Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Emanuelsson, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Swedish Biodiversity Centre.
    Karakin, Vladimir (Contributor)
    Russian Academy of Sciences, Far East Division, Vladivostok.
    von Bothmer, Roland (Contributor)
    Swedish University of Agriculture, Alnarp.
    The rural landscapes of Northeast Asia.2016Book (Other academic)
  • 42.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Gunnarsson, Urban
    Swedish Species Information Centre, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Strömquist, Lennart
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Social Sciences, Department of Human Geography.
    Bog vegetation re-mapped after 63 and 103 years: expansion of Rhynchospora alba (Studies on Skagershultsmossen 2)2023In: Mires and Peat, ISSN 1819-754X, E-ISSN 1819-754X, Vol. 29, p. 1-16, article id 18Article in journal (Refereed)
    Abstract [en]

    The vegetation in an area of the ombrotrophic bog Skagershultsmossen, South-Central Sweden, was mapped in 2010. The same area was previously surveyed in 1907 and 1970. Only small changes were found in 1970, in contrast to the situation in 2010, when a large shift in the vegetation was observed. The previously dominating vegetation type, lawns dominated by Eriophorum vaginatum, had more or less disappeared and was replaced by carpet vegetation dominated by Rhynchospora alba, Sphagnum tenellum and S. balticum. Also, the carpets dominated by Scheuchzeria palustris had decreased to a large extent. There are several possible climatic explanations behind the changes, and we suggest that increased frost action linked to the reduction in snow cover may be important. The shift in the vegetation has most certainly led to a decrease in peat productivity and, hence, a reduction in carbon sequestration by the bog is assumed. Skagershultsmossen is an important reference site for future studies of long-term vegetation changes.

    Download full text (pdf)
    fulltext
  • 43.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    "Det har vi vetat hela tiden!": akademikerna och lövängen för hundra år sedan2019In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 113, no 3/4, p. 219-231Article in journal (Refereed)
    Abstract [en]

    Mown meadows with scattered trees were a characteristic of the old Swedish landscape.  It has been an established truth that the botanists, particularly R. Sernander and H. Hesselman, did not understand that the meadows would turn into forests when abandoned, whereas the human geographer M. Sjöbeck in several publications from 1927 onwards made this clear. This view was supported by, i.a,. L.-G. Romell.

     We have scrutinized the literature and the minutes of the Plant Biology Seminar in Uppsala from 1892 to 1944, in order to understand Sernander’s views. Hesselman considered the matter uncertain. Sernander probably understood the dynamics also before 1927, but his standpoint was influenced by a wish to restore the postglacial broadleaved forests of which he saw the meadows as degraded relicts. This could be done by leaving meadows for free development. Gradually he saw the need also to maintain meadows and the cultural landscape as such. Several other botanists, e.g. G. Samuelsson and G. Einar Du Rietz, already early on understood the dependence of meadows on human management. 

  • 44.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Rydin, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Var Sellingaffären kulmen på en sekellång botanisk konflikt?2018In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 112, no 6, p. 380-393Article in journal (Refereed)
    Abstract [en]

    The 1950s saw a series of miscarriages of justice against public persons in Sweden. In one of these, the Royal Swedish Academy of Sciences tried to force Olof Selling from his professorship in paleobotany at the Swedish Museum of Natural History, on the basis of mental illness, but this failed after a long and public calamity. In his book Naturen inför rätta [Nature facing trial], Keith Wijkander (2017) claims that Selling was the victimof a century-long conflict between botanists in Uppsala and Stockholm,and places Selling in the Uppsala camp. We try to give a more balanced picture of the relationships between plant ecology in Uppsala and Stockholm during the early 20th century. R. Sernander, L.-G. Romell and G. E. Du Rietz are among the main actors. The fierce debates between the two camps make this an interesting period in Swedish botany.

  • 45.
    Backéus, Ingvar
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Skoglund, Jerry
    Department of Ecology, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Skarpe, Christina
    Campus Evenstad, Faculty of Applied Ecology, Agricultural Sciences and Biotechnology, Inland Norway University of Applied Sciences, Elverum, Norway.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Diameter growth of trees in miombo and acacia woodland in an eroded landscape in NE Tanzania2022In: African Journal of Ecology, ISSN 0141-6707, E-ISSN 1365-2028Article in journal (Refereed)
    Abstract [en]

    Diameter increment of trees typical of miombo and acacia woodland was studied dur- ing a period of 20 years in Kondoa district, Tanzania. The study was performed in permanent plots in a severely degraded area subjected to considerable restoration efforts. A total of 15 species were selected from a database collected within a pro- ject for monitoring the landscape recovery. Growth performance of African woodland species was searched for in the literature for comparison, and a comprehensive list of citations was compiled. We found growth to fall within the range reported in earlier studies, although growth varied both between and within species. There are reports that the radial increments of trees are unimodal over their lifespan, but we found no clear support. In several species, the annual growth increased with stem diameter. Growth during the rainy ENSO year 1997/98 was pairwise compared with the preced- ing two years and was found to be significantly higher during the wet year, pointing to soil water as a limiting factor. We conclude that free development is an alternative to tree planting on marginal land.

    Download full text (pdf)
    fulltext
  • 46.
    Bai, Yang
    et al.
    Shanghai Acad Environm Sci, Inst Appl Ecol, Shanghai 200233, Peoples R China..
    Jiang, Bo
    Changjiang Water Resources Protect Inst, Wuhan 430051, Peoples R China..
    Wang, Min
    Shanghai Acad Environm Sci, Inst Appl Ecol, Shanghai 200233, Peoples R China..
    Li, Hui
    Yunnan Univ, Sch Urban Construct & Management, Kunming 650091, Peoples R China..
    Alatalo, Juha M.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Qatar Univ, Coll Arts & Sci, Dept Biol & Environm Sci, POB 2713, Doha, Qatar..
    Huang, Shenfa
    Shanghai Acad Environm Sci, Inst Appl Ecol, Shanghai 200233, Peoples R China..
    New ecological redline policy (ERP) to secure ecosystem services in China2016In: Land use policy, ISSN 0264-8377, E-ISSN 1873-5754, Vol. 55, p. 348-351Article in journal (Refereed)
    Abstract [en]

    China is facing huge environmental problems, with its current rapid rate of urbanization and industrialization causing biodiversity loss, ecosystem degradation, and land resources degradation on a major scale. To overcome management conflicts and secure ecosystem services, China has proposed a new 'ecological redline policy' (ERP) using ecosystem services as a way to meet its targets. By giving environmental policy redline status, China is demonstrating strong commitment in its efforts to tackle environmental degradation and secure ecosystem services for the future. This is already having impact, as the Chinese Ministry of Environmental Protection and the National Development and Reform Commission are prepared to work together to implement the new environmental policy.

  • 47. Bakker, Jan P.
    et al.
    Hoffmann, Frank
    Ozinga, Wim A.
    Rosén, Eje
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Shading results in depletion of the soil seed bank2014In: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 32, no 5, p. 674-679Article in journal (Refereed)
    Abstract [en]

    To what extent is the decline of characteristic dry alvar species related to the decline in the soil seed bank during scrub encroachment? We recorded the number of flower stems in the vegetation in relation to light attenuation along an encroachment series progressing from open alvar through small gaps inside dense scrub of Juniperus communis (cover of 60%) to intact dense scrub (cover of 100%) on the island of oland, Sweden. This measurement of potential reproduction (number of flower stems) was then compared to the number of species in the soil seed bank at each site along the alvar encroachment series. Scrub encroachment results in light attenuation between and under the shrubs. The total number of flower stems averaged over all species was similar between gaps and open alvar, but that of alvar species was significantly lower in the gaps, indicating that light attenuation could reduce their seed set. Shading in gaps is related to depletion of the soil seed bank and loss of alvar species, particularly those that do not form a persistent soil seed bank.

  • 48. Bakker, Jan P.
    et al.
    Rosén, Eje
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Ozinga, Wim A.
    Bretfeld, Mario
    Feldt, Tobias
    Stahl, Julia
    Long-term effects of scrub clearance and litter removal on the re-establishment of dry alvar grassland species2012In: Annales Botanici Fennici, ISSN 0003-3847, E-ISSN 1797-2442, Vol. 49, no 1-2, p. 21-30Article in journal (Refereed)
    Abstract [en]

    Many characteristic dry alvar grassland species disappear after cessation of livestock grazing as a result of encroachment by Juniperus communis. We studied the re-establishment of these species after scrub clearance with and without the removal of the layer of litter and mosses in long-term (14 years) permanent plots. Most of the species belonging to the community species pool of dry alvar grassland species before clearance were found in permanent plots between 2 and 14 years after the clearance. A large part originated from vegetative spread of already occurring species in the established vegetation in the surroundings. Only a small part of the long-term persistent soil seed bank resulted in the re-establishment of alvar species. There was no significant difference in the traits soil seed bank, seed weight and long-distance dispersal by wind, dung or fur of animals of established and non-established species. Removal of litter and mosses positively affected the re-establishment of alvar species.

  • 49.
    Balanzategui, Daniel
    et al.
    GFZ German Res Ctr Geosci, Potsdam, Germany.;Humboldt Univ, Inst Geog, Berlin, Germany.;DAI German Archaeol Inst, Dept Nat Sci, Berlin, Germany..
    Nordhauss, Henry
    GFZ German Res Ctr Geosci, Potsdam, Germany..
    Heinrich, Ingo
    GFZ German Res Ctr Geosci, Potsdam, Germany.;Humboldt Univ, Inst Geog, Berlin, Germany.;DAI German Archaeol Inst, Dept Nat Sci, Berlin, Germany..
    Biondi, Franco
    Univ Nevada, Dept Nat Resources & Environm Sci, DendroLab, Reno, NV 89557 USA..
    Miley, Nicholas
    Univ Nevada, Dept Nat Resources & Environm Sci, DendroLab, Reno, NV 89557 USA..
    Hurley, Alexander G.
    GFZ German Res Ctr Geosci, Potsdam, Germany..
    Ziaco, Emanuele
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. GFZ German Res Ctr Geosci, Potsdam, Germany.
    Wood Anatomy of Douglas-Fir in Eastern Arizona and Its Relationship With Pacific Basin Climate2021In: Frontiers in Plant Science, E-ISSN 1664-462X, Vol. 12, article id 702442Article in journal (Refereed)
    Abstract [en]

    Dendroclimatic reconstructions, which are a well-known tool for extending records of climatic variability, have recently been expanded by using wood anatomical parameters. However, the relationships between wood cellular structures and large-scale climatic patterns, such as El Nino-Southern Oscillation (ENSO) and the Pacific Decadal Oscillation (PDO), are still not completely understood, hindering the potential for wood anatomy as a paleoclimatic proxy. To better understand the teleconnection between regional and local climate processes in the western United States, our main objective was to assess the value of these emerging tree-ring parameters for reconstructing climate dynamics. Using Confocal Laser Scanning Microscopy, we measured cell lumen diameter and cell wall thickness (CWT) for the period 1966 to 2015 in five Douglas-firs [Pseudotsuga menziesii (Mirb.) Franco] from two sites in eastern Arizona (United States). Dendroclimatic analysis was performed using chronologies developed for 10 equally distributed sectors of the ring and daily climatic records to identify the strongest climatic signal for each sector. We found that lumen diameter in the first ring sector was sensitive to previous fall-winter temperature (September 25(th) to January 23(rd)), while a precipitation signal (October 27(th) to February 13(th)) persisted for the entire first half of the ring. The lack of synchronous patterns between trees for CWT prevented conducting meaningful climate-response analysis for that anatomical parameter. Time series of lumen diameter showed an anti-phase relationship with the Southern Oscillation Index (a proxy for ENSO) at 10 to 14year periodicity and particularly in 1980-2005, suggesting that chronologies of wood anatomical parameters respond to multidecadal variability of regional climatic modes. Our findings demonstrate the potential of cell structural characteristics of southwestern United States conifers for reconstructing past climatic variability, while also improving our understanding of how large-scale ocean-atmosphere interactions impact local hydroclimatic patterns.

    Download full text (pdf)
    FULLTEXT01
  • 50.
    Balslev, Henrik
    et al.
    Aarhus Univ, Dept Biosci, Sect Ecoinformat & Biodivers, DK-8000 Aarhus, Denmark.
    Kristiansen, Soren M.
    Aarhus Univ, Dept Geosci, DK-8000 Aarhus, Denmark.
    Muscarella, Robert
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Aarhus Univ, Dept Biosci, Sect Ecoinformat & Biodivers, DK-8000 Aarhus, Denmark.
    Palm community transects and soil properties in western Amazonia2019In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 100, no 12, article id e02841Article in journal (Refereed)
    Abstract [en]

    Western Amazonia is a global biodiversity hotspot that encompasses extensive variation in geologic, climatic, and biotic features. Palms (Arecaceae) are among the most diverse and iconic groups of plants in the region with more than 150 species that exhibit extraordinary variation of geographical distributions, regional abundance patterns, and life history strategies and growth forms, and provide myriad ecosystem services. Understanding the ecological and evolutionary drivers that underpin palm distribution and abundance patterns may shed light on the evolution and ecology of the tropical forest biomes more generally. Edaphic conditions, in particular, are increasingly recognized as critical drivers of tropical plant diversity and distributions but data deficiencies inhibit our understanding of plant-soil relationships at broad scales, especially in the tropics. We present data from 546, 0.25-ha (5 x 500 m) georeferenced transects located throughout western Amazonia where all individual palms were identified, counted, and assigned to a life-history stage. Several environmental covariates were recorded along each transect and surface soil samples were collected from multiple points in N = 464 of transects. Altogether, the transects include 532,602 individuals belonging to 135 species. Variation among transects in terms of palm species richness and abundance is associated with major habitat types and soil properties. The soil properties including pH, acidity, all macronutrients for all samples, and texture, carbon, nitrogen, and micronutrients for some transects vary substantially across the study area, providing insight to broad-scale variation of tropical surface soils. The data provided here will help advance our understanding of plant distributions and abundance patterns, and associations with soil conditions. No copyright restrictions are associated with this data set but please cite this paper if data are used for publication.

    Download full text (pdf)
    fulltext
1234567 1 - 50 of 822
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf