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  • 1. Aarrestad, P. A.
    et al.
    Hytteborn, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Masunga, G.
    Skarpe, C.
    Vegetation: Between Soils and Herbivores2014Inngår i: 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, s. 61-88Kapittel i bok, del av antologi (Fagfellevurdert)
    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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 Botswana2011Inngår i: Journal of Arid Environments, ISSN 0140-1963, E-ISSN 1095-922X, Vol. 75, nr 3, s. 290-297Artikkel i tidsskrift (Fagfellevurdert)
    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.
    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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Unneberg, Per
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för cell- och molekylärbiologi, Molekylär 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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik. 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 DNA2018Inngår i: Quaternary Science Reviews, ISSN 0277-3791, E-ISSN 1873-457X, Vol. 181, s. 19-29Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 4.
    Akiyama, Reiko
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Life History and Tolerance and Resistance against Herbivores in Natural Populations of Arabidopsis thaliana2011Doktoravhandling, med artikler (Annet vitenskapelig)
    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.

    Delarbeid
    1. Selection on flowering time in three natural populations of Arabidopsis thaliana
    Åpne denne publikasjonen i ny fane eller vindu >>Selection on flowering time in three natural populations of Arabidopsis thaliana
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-159506 (URN)
    Forskningsfinansiär
    Swedish Research Council
    Tilgjengelig fra: 2011-10-06 Laget: 2011-10-03 Sist oppdatert: 2011-11-10
    2. Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana
    Åpne denne publikasjonen i ny fane eller vindu >>Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana
    2014 (engelsk)Inngår i: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 27, nr 1, s. 193-199Artikkel i tidsskrift (Fagfellevurdert) 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.

    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-159664 (URN)10.1111/jeb.12293 (DOI)000329254500018 ()
    Forskningsfinansiär
    Swedish Research Council
    Tilgjengelig fra: 2011-10-06 Laget: 2011-10-06 Sist oppdatert: 2017-12-08bibliografisk kontrollert
    3. Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)
    Åpne denne publikasjonen i ny fane eller vindu >>Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)
    2012 (engelsk)Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, nr 1, s. e30015-Artikkel i tidsskrift (Fagfellevurdert) 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.

    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-159665 (URN)10.1371/journal.pone.0030015 (DOI)000301457200028 ()
    Forskningsfinansiär
    Swedish Research Council
    Tilgjengelig fra: 2011-10-06 Laget: 2011-10-06 Sist oppdatert: 2017-12-08bibliografisk kontrollert
    4. Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thaliana
    Åpne denne publikasjonen i ny fane eller vindu >>Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thaliana
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-159685 (URN)
    Forskningsfinansiär
    Swedish Research Council
    Tilgjengelig fra: 2011-10-06 Laget: 2011-10-06 Sist oppdatert: 2011-11-10
  • 5.
    Akiyama, Reiko
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Noack, Sibylle
    Department of Zoology, Stockholm University.
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Genetic variation in leaf morphology and resistance against specialist and generalist insect herbivores in natural populations of Arabidopsis thalianaManuskript (preprint) (Annet vitenskapelig)
  • 6.
    Akiyama, Reiko
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Conflicting selection on the timing of germination in a natural population of Arabidopsis thaliana2014Inngår i: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 27, nr 1, s. 193-199Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 7.
    Akiyama, Reiko
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Magnitude and timing of leaf damage affect seed production in a natural population of Arabidopsis thaliana (Brassicaceae)2012Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 7, nr 1, s. e30015-Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 8.
    Akiyama, Reiko
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ågren, Jon
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Selection on flowering time in three natural populations of Arabidopsis thalianaManuskript (preprint) (Annet vitenskapelig)
  • 9.
    Alatalo, Juha M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 tundra2014Inngår i: Alpine Botany, ISSN 1664-2201, E-ISSN 1664-221X, Vol. 124, nr 2, s. 81-91Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 10.
    Alatalo, Juha M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Jagerbrand, 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 change2015Inngår i: Ecological Indicators, ISSN 1470-160X, E-ISSN 1872-7034, Vol. 58, s. 77-85Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 11.
    Alatalo, Juha M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Little, Chelsea J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 enhancement2014Inngår i: SpringerPlus, E-ISSN 2193-1801, Vol. 3, artikkel-id 157Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 12.
    Alatalo, Juha M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Little, Chelsea J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 change2014Inngår i: PeerJ, ISSN 2167-8359, E-ISSN 2167-8359, Vol. 2, s. e406-Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 13.
    Alatalo, Juha M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Little, Chelsea J.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Jagerbrand, Annika K.
    Molau, Ulf
    Vascular plant abundance and diversity in an alpine heath under observed and simulated global change2015Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 5, artikkel-id 10197Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 14.
    Alatalo, Juha M.
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ostapenko, Oksana V.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    The Swedish system: The image cracking when taking a closer look2014Inngår i: Geoforum, ISSN 0016-7185, E-ISSN 1872-9398, Vol. 53, s. 82-83Artikkel, forskningsoversikt (Fagfellevurdert)
    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".

  • 15. 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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Bronikowski, Anne M.
    Reproductive aging patterns in primates reveal that humans are distinct2013Inngår i: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 110, nr 33, s. 13440-13445Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 16.
    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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 Italy2019Inngår i: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 30, nr 3, s. 564-574Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 17.
    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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 Italy2018Inngår i: Rendiconti Lincei SCIENZE FISICHE E NATURALI, ISSN 2037-4631, E-ISSN 1720-0776, Vol. 29, nr 2, s. 343-354Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 18. Armbruster, W. Scott
    et al.
    Hansen, Thomas F.
    Pélabon, Christophe
    Pérez-Barrales, Rocio
    Maad, Johanne
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    The adaptive accuracy of flowers: measurement and microevolutionary patterns2009Inngår i: Annals of Botany, ISSN 0305-7364, E-ISSN 1095-8290, Vol. 103, nr 9, s. 1529-1545Artikkel i tidsskrift (Fagfellevurdert)
  • 19.
    Asplund, Linnea
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och evolution.
    Hagenblad, Jenny
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Leino, Matti W.
    Re-evaluating the history of the wheat domestication gene NAM-B1 using historical plant material2010Inngår i: Journal of Archaeological Science, ISSN 0305-4403, E-ISSN 1095-9238, Vol. 37, nr 9, s. 2303-2307Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 20.
    Asplund, Linnea
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Leino, Matti W.
    Hagenblad, Jenny
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Allelic Variation at the Rht8 Locus in a 19th Century Wheat Collection2012Inngår i: Scientific World Journal, ISSN 1537-744X, E-ISSN 1537-744X, s. 385610-Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 21. Avia, Komlan
    et al.
    Karkkainen, Katri
    Lagercrantz, Ulf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Savolainen, Outi
    Association of FLOWERING LOCUS T/TERMINAL FLOWER 1-like gene FTL2 expression with growth rhythm in Scots pine (Pinus sylvestris)2014Inngår i: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 204, nr 1, s. 159-170Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 22.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Dynamik och evolution på de östafrikanska bergen2017Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 111, nr 5, s. 228-239Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

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

  • 23.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Ett etnobotaniskt livsverk2015Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 109, nr 6, s. 346-347Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 24.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Gunnar Björkman och hans expedition till Lule lappmark 1924: Gunnar Björkman’s expedition to Swedish Lapland in 19242013Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 107, nr 6, s. 354-358Artikkel i tidsskrift (Annet vitenskapelig)
    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.

  • 25.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Mossflora över Sankta Helena2013Inngår i: Myrinia, ISSN 1102-4194, Vol. 23, s. 84-87Artikkel i tidsskrift (Annet vitenskapelig)
    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.

  • 26.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Centrum för biologisk mångfald.
    Om São Tomé, begonior och öar i havet2018Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 112, nr 1, s. 32-40Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 27.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Centrum för biologisk mångfald. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Sankta Helena: en hotad endemisk flora. 1. Den ursprungliga floran och vegetationen och den historiska utvecklingen2014Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, nr 3-4, s. 206-218Artikkel i tidsskrift (Annet vitenskapelig)
    Abstract [en]

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

  • 28.
    Backéus, Ingvar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Centrum för biologisk mångfald. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Sankta Helena: en hotad endemisk flora. 2. situationen i dag2014Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 108, nr 5, s. 232-244Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

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

  • 29.
    Backéus, Ingvar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Centrum för biologisk mångfald. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Emanuelsson, Urban
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Centrum för biologisk mångfald.
    Karakin, Vladimir ()
    Russian Academy of Sciences, Far East Division, Vladivostok.
    von Bothmer, Roland ()
    Swedish University of Agriculture, Alnarp.
    The rural landscapes of Northeast Asia.2016Bok (Annet vitenskapelig)
  • 30.
    Backéus, Ingvar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Hytteborn, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    "Det har vi vetat hela tiden" – akademikerna och lvängen för hundra år sedan.2019Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 113, nr 3–4, s. 219-231Artikkel i tidsskrift (Fagfellevurdert)
    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. 

  • 31.
    Backéus, Ingvar
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Hytteborn, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Rydin, Håkan
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Var Sellingaffären kulmen på en sekellång botanisk konflikt?2018Inngår i: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 112, nr 6, s. 380-393Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 32.
    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 universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 China2016Inngår i: Land use policy, ISSN 0264-8377, E-ISSN 1873-5754, Vol. 55, s. 348-351Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 33. Bakker, Jan P.
    et al.
    Hoffmann, Frank
    Ozinga, Wim A.
    Rosén, Eje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Shading results in depletion of the soil seed bank2014Inngår i: Nordic Journal of Botany, ISSN 0107-055X, E-ISSN 1756-1051, Vol. 32, nr 5, s. 674-679Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 34. Bakker, Jan P.
    et al.
    Rosén, Eje
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och 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 species2012Inngår i: Annales Botanici Fennici, ISSN 0003-3847, E-ISSN 1797-2442, Vol. 49, nr 1-2, s. 21-30Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 35.
    Bartoszek, Krzysztof
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen.
    Glemin, Sylvain
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution. CNRS Univ Montpellier IRD EPHE, UMR ISEM 5554, Montpellier, France..
    Kaj, Ingemar
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Matematisk-datavetenskapliga sektionen, Matematiska institutionen.
    Lascoux, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Using the Ornstein-Uhlenbeck process to model the evolution of interacting populations2017Inngår i: Journal of Theoretical Biology, ISSN 0022-5193, E-ISSN 1095-8541, Vol. 429, s. 35-45Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Ornstein-Uhlenbeck (OU) process plays a major role in the analysis of the evolution of phenotypic traits along phylogenies. The standard OU process includes random perturbations and stabilizing selection and assumes that species evolve independently. However, evolving species may interact through various ecological process and also exchange genes especially in plants. This is particularly true if we want to study phenotypic evolution among diverging populations within species. In this work we present a straightforward statistical approach with analytical solutions that allows for the inclusion of adaptation and migration in a common phylogenetic framework, which can also be useful for studying local adaptation among populations within the same species. We furthermore present a detailed simulation study that clearly indicates the adverse effects of ignoring migration. Similarity between species due to migration could be misinterpreted as very strong convergent evolution without proper correction for these additional dependencies. Finally, we show that our model can be interpreted in terms of ecological interactions between species, providing a general framework for the evolution of traits between "interacting" species or populations.

  • 36. Bella, Eleni
    et al.
    Liepelt, Sascha
    Parducci, Laura
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Drouzas, Andreas D.
    Genetic insights into the hybrid origin of Abies borisii-regis Mattf.2015Inngår i: Plant Systematics and Evolution, ISSN 0378-2697, E-ISSN 1615-6110, Vol. 301, nr 2, s. 749-759Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Abies × borisii-regis Mattf. (King Boris fir) is a taxon endemic to the southern Balkan Peninsula, described as a hybrid between the widespread A. alba Mill. (Silver fir) and the Greek endemic A. cephalonica Loud (Greek fir). Even though A. × borisii-regis has attracted much research attention in the past, its origin, geographical distribution and taxonomic status are not fully elucidated and molecular evidence for hybridization is missing. To shed more light on this issue, we analyzed representative populations from these three Abies taxa using paternally inherited (chloroplast) and maternally inherited (mitochondrial) DNA markers. Both Silver and Greek fir could be clearly distinguished using mitochondrial markers, while we observed a mixture of maternal lineages in theA. × borisii-regis populations. In contrast, using chloroplast markers, we could not identify species-specific haplotypes, but a neighbor-joining analysis of population genetic distances revealed two separate clusters for the Silver fir and the Greek fir, while the A. × borisii-regis populations were placed in intermediate positions. Our results are in agreement with the hypothesis that the A. ×borisii-regis populations investigated are a result of hybridization between A. cephalonica and A. alba.

  • 37.
    Bengtsson, Fia
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.
    Functional Traits in Sphagnum2019Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Peat mosses (Sphagnum) are ecosystem engineers that largely govern carbon sequestration in northern hemisphere peatlands. I investigated functional traits in Sphagnum species and addressed the questions: (I) Are growth, photosynthesis and decomposition and the trade-offs between these traits related to habitat or phylogeny?, (II) Which are the determinants of decomposition and are there trade-offs between metabolites that affect decomposition?, (III) How do macro-climate and local environment determine growth in Sphagnum across the Holarctic?, (IV) How does N2 fixation vary among different species and habitats?, (V) How do species from different microtopographic niches avoid or tolerate desiccation, and are leaf and structural traits adaptations to growth high above the water table?

    Photosynthetic rate and decomposition in laboratory conditions (innate growth and decay resistance) were related to growth and decomposition in their natural habitats. We found support for a trade-off between growth and decay resistance, but innate qualities translated differently to field responses in different species. There were no trade-offs between production of different decay-affecting metabolites. Their production is phylogenetically controlled, but their effects on decay are modified by nutrient availability in the habitat. Modelling growth of two species across the Holarctic realm showed that precipitation, temperature and vascular plant cover are the best predictors of performance, but responses were stronger for the wetter growing species. N2 fixation rates were positively related to moss decomposability, field decomposition and tissue phosphorus concentration. Hence, higher decomposition can lead to more nutrients available to N2-fixing microorganisms, while higher concentrations of decomposition-hampering metabolites may impede N2 fixation. A mesocosm experiment, testing effects of water level drawdown on water content and chlorophyll fluorescence, showed that either slow water loss or high maximum water holding capacity can lead to desiccation avoidance. Furthermore, leaf anatomical traits rather than structural traits affected the water economy.

    This thesis has advanced the emerging field of trait ecology in Sphagnum by comparing many species and revealing novel mechanisms and an ever more complex picture of Sphagnum ecology. In addition, the species-specific trait measurements of this work offers opportunities for improvements of peatland ecosystem models.

    Delarbeid
    1. Photosynthesis, growth, and decay traits in Sphagnum – a multispecies comparison
    Åpne denne publikasjonen i ny fane eller vindu >>Photosynthesis, growth, and decay traits in Sphagnum – a multispecies comparison
    2016 (engelsk)Inngår i: Ecology and Evolution, ISSN 2045-7758, E-ISSN 2045-7758, Vol. 6, nr 10, s. 3325-3341Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Peat mosses (Sphagnum) largely govern carbon sequestration in Northern Hemisphere peatlands. We investigated functional traits related to growth and decomposition in Sphagnum species. We tested the importance of environment and phylogeny in driving species traits and investigated trade-offs among them. We selected 15 globally important Sphagnum species, representing four sections (subgenera) and a range of peatland habitats. We measured rates of photosynthesis and decomposition in standard laboratory conditions as measures of innate growth and decay potential, and related this to realized growth, production, and decomposition in their natural habitats. In general, we found support for a trade-off between measures of growth and decomposition. However, the relationships are not strong, with r ranging between 0.24 and 0.45 for different measures of growth versus decomposition. Using photosynthetic rate to predict decomposition in standard conditions yielded R2 = 0.20. Habitat and section (phylogeny) affected the traits and the trade-offs. In a wet year, species from sections Cuspidata and Sphagnum had the highest production, but in a dry year, differences among species, sections, and habitats evened out. Cuspidata species in general produced easily decomposable litter, but their decay in the field was hampered, probably due to near-surface anoxia in their wet habitats. In a principal components analysis, PCA, photosynthetic capacity, production, and laboratory decomposition acted in the same direction. The species were imperfectly clustered according to vegetation type and phylogeny, so that some species clustered with others in the same section, whereas others clustered more clearly with others from similar vegetation types. Our study includes a wider range of species and habitats than previous trait analyses in Sphagnum and shows that while the previously described growth–decay trade-off exists, it is far from perfect. We therefore suggest that our species-specific trait measures offer opportunities for improvements of peatland ecosystem models. Innate qualities measured in laboratory conditions translate differently to field responses. Most dramatically, fast-growing species could only realize their potential in a wet year. The same species decompose fast in laboratory, but their decomposition was more retarded in the field than that of other species. These relationships are crucial for understanding the long-term dynamics of peatland communities.

    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-284287 (URN)10.1002/ece3.2119 (DOI)000376646700024 ()27103989 (PubMedID)
    Forskningsfinansiär
    Swedish Research CouncilSwedish Research Council FormasThe Royal Swedish Academy of Sciences
    Tilgjengelig fra: 2016-04-16 Laget: 2016-04-16 Sist oppdatert: 2019-02-01bibliografisk kontrollert
    2. Biochemical determinants of litter quality in 15 species of Sphagnum
    Åpne denne publikasjonen i ny fane eller vindu >>Biochemical determinants of litter quality in 15 species of Sphagnum
    2018 (engelsk)Inngår i: Plant and Soil, ISSN 0032-079X, E-ISSN 1573-5036, Vol. 425, nr 1-2, s. 161-176Artikkel i tidsskrift (Fagfellevurdert) Published
    Abstract [en]

    Background and aims Sphagnum mosses are ecosystem engineers that create and maintain boreal peatlands. With unique biochemistry, waterlogging and acidifying capacities, they build up meters-thick layers of peat, reducing competition and impeding decomposition. We quantify within-genus differences in biochemical composition to make inferences about decay rates, related to hummock-hollow and fen-bog gradients and to phylogeny. Methods We sampled litter from 15 Sphagnum species, abundant over the whole northern hemisphere. We used regression and Principal Components Analysis (PCA) to evaluate general relationships between litter quality parameters and decay rates measured under laboratory and field conditions. Results Both concentrations of the polysaccharide sphagnan and the soluble phenolics were positively correlated with intrinsic decay resistance, however, so were the previously understudied lignin-like phenolics. More resistant litter had more of all the important metabolites; consequently, PC1 scores were related to lab mass loss (R-2 = 0.57). There was no such relationship with field mass loss, which is also affected by the environment. PCA also revealed that metabolites clearly group Sphagnum sections (subgenera). Conclusions We suggest that the commonly stated growth-decomposition trade-off is largely due to litter quality. We show a strong phylogenetic control on Sphagnum metabolites, but their effects on decay are affected by nutrient availability in the habitat.

    Emneord
    Peatland, Decay resistance, Sphagnan, Phenolics, Lignin, Hummock-hollow
    HSV kategori
    Identifikatorer
    urn:nbn:se:uu:diva-354249 (URN)10.1007/s11104-018-3579-8 (DOI)000430992300011 ()
    Forskningsfinansiär
    Swedish Research CouncilThe Royal Swedish Academy of Sciences
    Merknad

    Correction in: PLANT AND SOIL, Volume: 439, Issue: 1-2, Pages: 569-572, Special Issue: SI, DOI: 10.1007/s11104-019-04046-5

    Tilgjengelig fra: 2018-06-29 Laget: 2018-06-29 Sist oppdatert: 2019-08-16bibliografisk kontrollert
    3. Environmental drivers of Sphagnum growth in mires across the Holarctic region
    Åpne denne publikasjonen i ny fane eller vindu >>Environmental drivers of Sphagnum growth in mires across the Holarctic region
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Emneord
    climate, global change, NPP, peatlands, peat mosses, nitrogen deposition
    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik; Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-375010 (URN)
    Tilgjengelig fra: 2019-01-24 Laget: 2019-01-24 Sist oppdatert: 2019-02-01
    4. Variation in symbiotic Nfixation among Sphagnum and feather mosses
    Åpne denne publikasjonen i ny fane eller vindu >>Variation in symbiotic Nfixation among Sphagnum and feather mosses
    Vise andre…
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Emneord
    diazotrophs, peat moss, bog, peatland, nitrogen, phosphorus, carbon, nutrient cycling, traits, boreal forest
    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-375008 (URN)
    Tilgjengelig fra: 2019-01-24 Laget: 2019-01-24 Sist oppdatert: 2019-02-01
    5. Mechanisms behind species-specific water economy responses to water level drawdown in peat mosses
    Åpne denne publikasjonen i ny fane eller vindu >>Mechanisms behind species-specific water economy responses to water level drawdown in peat mosses
    (engelsk)Manuskript (preprint) (Annet vitenskapelig)
    Emneord
    peat mosses, water economy, capitulum water content, bulk density, hyaline cell, pore size, leaf anatomy
    HSV kategori
    Forskningsprogram
    Biologi med inriktning mot ekologisk botanik
    Identifikatorer
    urn:nbn:se:uu:diva-375009 (URN)
    Tilgjengelig fra: 2019-01-24 Laget: 2019-01-24 Sist oppdatert: 2019-02-01
  • 38.
    Bengtsson, Fia
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik, Växtekologi och evolution.