sh.sePublications
Change search
Refine search result
12 51 - 71 of 71
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • harvard-anglia-ruskin-university
  • apa-old-doi-prefix.csl
  • 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.
  • 51.
    Ramula, Satu
    et al.
    Södertörn University, School of Life Sciences.
    Dinnétz, Patrik
    University of Kalmar.
    Lehtilä, Kari
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Spatial data replacing temporal data in population viability analyses: An empirical investigation for plants2009In: Basic and Applied Ecology, ISSN 1439-1791, E-ISSN 1618-0089, Vol. 10, no 5, p. 401-410Article in journal (Refereed)
    Abstract [en]

    In conservation management, there is an urgent need for estimates of population viability and for knowledge of the contributions of different life-history stages to population growth rates. Collection of long-term demographic data from a study population is time-consuming and may considerably delay the start of proper management actions. We examined the possibility of replacing a long-term temporal data set (demographic data from several years within a population) with a short-term spatial data set (demographic data from different populations for the same subset of two continuous years) for stochastic estimates of population viability. Using matrix population models for ten perennial plant species, we found that the matrix elements of spatial data sets often deviated from those of temporal data sets and that matrix elements generally varied more spatially than temporally. The appropriateness of replacing temporal data with spatial data depended on the subset of years and populations used to estimate stochastic population growth rates (log lambda(s)). Still, the precision of log lambda(s) estimates measured as variation in the yearly change of logarithmic population size rarely differed significantly between the spatial and temporal data sets. Since a spatiotemporal comparison of matrix elements and their variation cannot be used to assess whether spatial and temporal data sets are interchangeable, we recommend further research on the topic.

  • 52. Reitalu, Triin
    et al.
    Sykes, Martin T.
    Johansson, Lotten M.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Hall, Karin
    Vanderwalle, Marie
    Prentice, Honor C.
    Small-scale plant species richness and evenness in semi-natural grasslands respond differently to habitat fragmentation2009In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 142, no 4, p. 899-908Article in journal (Refereed)
    Abstract [en]

    The study explores whether small-scale species diversity, species evenness and species richness in semi-natural grassland communities are similarly associated with present management regime and/or present and historical landscape context (percentage of different land-cover types in the surroundings). Species diversity, evenness and richness were recorded within 441 50 × 50 cm grassland plots in 4.5 × 4.5 km agricultural landscape on Öland, Sweden. Recent and historical land-cover maps (years 2004, 1959, 1938, 1835, and 1800) were used to characterize the present and past landscape context of the sampled vegetation plots. Partial regression and simultaneous autoregressive models were used to explore the relationships between species diversity measures (Shannon diversity, richness and evenness) and different explanatory variables while accounting for spatial autocorrelation in the data. The results indicated that species richness was relatively sensitive to grassland isolation, while the response of species evenness to isolation was characterized by a degree of inertia. Because the richness and evenness components of species diversity may respond differently to habitat fragmentation, we suggest that monitoring projects and empirical studies that focus on changes in biodiversity in semi-natural grasslands should include the assessment of species evenness – as a complement to the assessment of species richness. In addition, our results indicated that the development and persistence of a species-rich and even grassland vegetation was favoured in areas that have historically (in the 19th century) been surrounded by grasslands. Information on landscape history should, whenever possible, be incorporated into the planning of strategies for grassland conservation.

  • 53.
    Reyhanian, Nasim
    et al.
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    Volkova, Kristina
    Södertörn University, School of Life Sciences, Environmental science.
    Hallgren, Stefan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Bollner, Tomas
    Södertörn University, School of Life Sciences, Biology.
    Olsson, Per-Erik
    Olsén, K Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Porsch Hällström, Inger
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    17α-Ethinyl estradiol affects anxiety and shoaling behavior in adult male zebra fish (Danio rerio)2011In: Aquatic Toxicology, ISSN 0166-445X, E-ISSN 1879-1514, Vol. 105, p. 41-48Article in journal (Refereed)
  • 54.
    Robeck, Alexandra
    et al.
    Södertörn University, School of Life Sciences.
    Mattsson, Jan-Eric
    Södertörn University, School of Life Sciences, Biology.
    Lindblom, Louise
    University of Bergen, Museum of Natural History.
    Patterns of genetic diversity of Pseudevernia furfuracea compared to chemistry, morphology and substrate ecology2006Conference paper (Other academic)
  • 55. Saheed, Sefiu A.
    et al.
    Jonsson, Lisbeth M. V.
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Botha, Christaan E. J.
    Russian wheat aphid causes greater reduction in phloem transport apacity of barley leaves than bird cherry-oat aphid.2010In: Acta Botanica Croatica, ISSN 0365-0588, E-ISSN 1847-8476, Vol. 69, no 1, p. 7-18Article in journal (Refereed)
    Abstract [en]

    The effects of feeding by the Russian wheat aphid (RWA). Dutraplu.s nom! ordvilko and the Bird cherry-oat aphid (BC A). Rhopaloppluan pad, L on he transport capacity of barley Holdeum vulgare L leaves were nvestigated and compated with a view to i-elan ng these effects to the isible symptoms shown by the respective infested plants RWA causes xtensive chlorosis and neciosis on an infested plant whereas I3CA auses no obseivable symptoms Our results using the xenobiotic. phloem obile Bum ophole. 5, 6 carboxyBurn escei n chacetate (5. 6-CFDA) evealed striking ch fletences in damage to the transpol t of ssimilates thiough the phloem by these two aphids The result clearly uggests that short-term feeding by RWA causes a reduction in tiansport f assimikites and a mole severe reduction oi pei haps even permanent essation of transport during long-term feed111,2. In contrast. feechntz y BCA does not lead to a !milked dect ease in transport do ring hort-term feeding period. howevei, a !eduction in the uanspoit was ecorded donne long-term feeding activities These iesults perhaps uggest that damage to ti ansport capacities of the barley leaves ppeals lobe partly responsible for the observed symptoms in WIA-infested plants and the lack of them during BCA in symptoms such as eduction ol cessation in transport of assionlates to growing tissues ay lead to such observable symptoms

  • 56. Saheed, Sefiu Adekilekun
    et al.
    Botha, Christiaan Edward Johannes
    Liu, Lin
    Jonsson, Lisbeth
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Comparison of structural damage caused by Russian wheat aphid (Diuraphis noxia) and Bird cherry-oat aphid (Rhopalosiphum padi) in a susceptible barley cultivar, Hordeum vulgare cv. Clipper2007In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 129, no 2, p. 429-435Article in journal (Refereed)
    Abstract [en]

    The Russian wheat aphid (RWA, (Diuraphis noxia) and the Bird cherry-oat aphid (BCA, (Rhopalosiphum padi L.) cause severe damage to grain crops, including barley. An investigation of the effects of these aphids on a susceptible cultivar revealed that BCA-infested barley plants remained healthy looking for 2 weeks after feeding commenced. In contrast, signs of stress and damage, including chlorosis and leaf necrosis were evident in RWA-infested plants. Our study suggests that damage to the vascular tissue because of sustained feeding by BCA was not as extensive as that caused by RWA. In addition, there is a marked difference in the salivary secretion pattern within xylem elements punctured by aphids tapping the xylem for water. RWA deposit electron-dense, amorphous to smooth saliva, which completely encases the inner walls of affected elements, and saliva encases pit membranes between xylem elements, and between xylem vessels and xylem parenchyma. Xylem tapped by BCA contained more granular saliva, which apparently does not occlude vessel wall apertures or the pit membranes to the same extent, as was observed with RWA. Damage to phloem tissue, including phloem parenchyma elements, sieve tube-companion cell (CC-ST) complexes as well as thick-walled ST, was extensive. Plasmodesmata between phloem parenchyma elements as well as pore plasmodesmata between the CC and ST were occluded by callose. We conclude that severe, perhaps permanent damage to conducting elements in RWA-infested leaves may be responsible for the detrimental chlorosis and necrosis symptoms. These symptoms are absent in BCA-infested plants.

  • 57. Saheed, Sefiu
    et al.
    Cierlik, Izabela
    Södertörn University, School of Life Sciences.
    Larsson, Kristina A. E.
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Delp, Gabriele
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Bradley, Graeme
    Jonsson, Lisbeth M. V.
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Botha, Christiaan E. J.
    Stronger induction of callose deposition in barley by Russian wheat aphid than bird cherry-oat aphid is not associated with differences in callose synthase or beta-1,3-glucanase transcript abundance2009In: Physiologia Plantarum: An International Journal for Plant Biology, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 135, no 2, p. 150-161Article in journal (Refereed)
    Abstract [en]

    The effects of infestation by the bird cherry-oat aphid (BCA), (Rhopalosiphum padi L) and the Russian wheat aphid (RWA) (Diuraphis noxia Mordvilko) on callose deposition and transcription of genes related to callose accumulation were investigated in barley (Hordeum vulgare L. cv. Clipper). The BCA, which gives no visible symptoms, induced very limited callose deposition, even after 14 days of infestation. In contrast, RWA, which causes chlorosis, white and yellow streaking and leaf rolling, induced callose accumulation already after 24 h in longitudinal leaf veins. The deposition was pronounced after 72 h, progressing during 7 and 14 days of infestation. In RWA-infested source leaves, callose was also induced in longitudinal veins basipetal to the aphid-infested tissue, whereas in sink leaves, more callose deposition was found above the feeding sites. Eight putative callose synthase genes were identified in a database search, of which seven were expressed in the leaves, but with similar transcript accumulation in control and aphid-infested tissue. Five out of 12 examined beta-1,3-glucanases were expressed in the leaves. All five were upregulated in RWA-infested tissue, but only two in BCA-infested tissue, and to a lesser extent than by RWA. The results suggest that callose accumulation may be partly responsible for the symptoms resulting from RWA infestation and that a callose-inducing signal may be transported in the phloem. Furthermore, it is concluded that the absence of callose deposition in BCA-infested leaves is not because of a stronger upregulation of callose-degrading beta-1,3-glucanases in this tissue, as compared to RWA-infested leaves.

  • 58.
    Simoff, Ivailo
    et al.
    Södertörn University, School of Life Sciences.
    Moradi, Hossein
    Södertörn University, School of Life Sciences.
    Nygård, Odd
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Functional characterization of ribosomal protein L15 from Saccharomyces cerevisiae2009In: Current Genetics, ISSN 0172-8083, E-ISSN 1432-0983, Vol. 55, no 2, p. 111-125Article in journal (Refereed)
    Abstract [en]

    In this study we provide general information on the little studied eukaryotic ribosomal protein rpL15. Saccharomyces cerevisiae has two genes, YRPL15A and YRPL15B that could potentially code for yeast rpL15 (YrpL15). YRPL15A is essential while YRPL15B is dispensable. However, a plasmid-borne copy of the YRPL15B gene, controlled by the GAL1 promoter or by the promoter controlling expression of the YRPL15A gene, can functionally complement YrpL15A in yeast cells, while the same gene controlled by the authentic promoter is inactive. Analysis of the levels of YrpL15B-mRNA in yeast cells shows that the YRPL15B gene is inactive in transcription. The function of YrpL15A is highly resilient to single and multiple amino acid substitutions. In addition, minor deletions from both the N- and C-terminal ends of YrpL15A has no effect on protein function, while addition of a C-terminal tag that could be used for detection of plasmid-encoded YrpL15A is detrimental to protein function. YrpL15A could also be replaced by the homologous protein from Arabidopsis thaliana despite almost 30% differences in the amino acid sequence, while the more closely related protein from Schizosaccharomyces pombe was inactive. The lack of function was not caused by a failure of the protein to enter the yeast nucleus.

  • 59. Souter, Petra
    et al.
    Henriksson, Oskar
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Olsson, Niklas
    Södertörn University, School of Life Sciences.
    Grahn, Mats
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Patterns of genetic structuring in the coral Pocillopora damicornis on reefs in East Africa.2009In: BMC Ecology, ISSN 1472-6785, E-ISSN 1472-6785, Vol. 9, p. 19-Article in journal (Refereed)
    Abstract [en]

    This study showed that population differentiation in P. damicornis varied over spatial scales and that this variability occurred at both evolutionary and ecological time scales. This paradox is discussed in light of stochastic recruitment and small scale population structures found in other species of coral. The study also identifies potential source reefs, such as those within Mnemba Conservation area near Zanzibar and genetically isolated reefs such as those within Malindi Marine National Park and Reserve in northern Kenya.

  • 60. Stacey, N. E.
    et al.
    Van der Kraak, G. J.
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Male primer endocrine responses to preovulatory female cyprinids under natural conditions in Sweden2012In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 80, no 1, p. 147-165Article in journal (Refereed)
    Abstract [en]

    This study investigated two related aspects of male-female reproductive interactions in the family Cyprinidae: (1) whether ovulating female rudd Scardinius erythrophthalmus (subfamily Leuciscinae) induce endocrine and gonadal priming responses in conspecific males, a phenomenon which has been described only in species from the subfamily Cyprininae such as goldfish, Carassius auratus, crucian carp Carassius carassius and common carp, Cyprinus carpio and (2) whether the stimuli mediating these responses are species-specific. Field studies of three sympatric European cyprinids, two leuciscins (S. erythrophthalmus and white bream Blicca bjoerkna) and one cyprinin (C. carassius), were conducted on fishes captured in Sweden in the spawning season and held in net pens under natural conditions. As previously reported in C. carassius, male S. erythrophthalmus increased milt (sperm and seminal fluid) volume and plasma concentrations of the sperm maturation hormone 4-pregnen-17,20 beta-diol-3-one (17,20 beta-P) when they were held with female S. erythrophthalmus induced to ovulate by injection of Ovaprim (GnRH analogue plus dopamine antagonist). Male S. erythrophthalmus had larger milt volumes than male C. carassius prior to and following exposure to ovulatory conspecifics, but exhibited a smaller proportional milt increase in response to stimulation, suggesting species differences in sperm allocation at spawning. The presence of female S. erythrophthalmus and B. bjoerkna did not affect milt volumes of C. carassius under two experimental conditions: (1) ovulating S. erythrophthalmus and B. bjoerkna did not increase the milt volumes of C. carassius and (2) S. erythrophthalmus and B. bjoerkna did not interfere with the milt volume increase induced in male C. carassius by ovulating conspecifics. These results suggest that, as in C. auratus, C. carassius and C. carpio (subfamily Cyprininae), female S. erythrophthalmus (subfamily Leuciscinae) release a preovulatory pheromone that exerts priming effects on male hormones and sperm allocation. The findings also indicate that C. carassius discriminate between the reproductive odours of conspecifics and heterospecifics.

  • 61.
    Svanberg, Ingvar
    et al.
    Institutionen för rysslandsstudier Uppsala universitet.
    Bonow, Madeleine
    Södertörn University, School of Life Sciences, Geography.
    Olsén, Håkan
    Södertörn University, School of Life Sciences, Biology.
    Fish ponds in Scania, and Linnaeus's attempt to promote aquaculture in Sweden2012In: Svenska Linnésällskapets årsskrift, ISSN 0375-2038, p. 85-100Article in journal (Other academic)
  • 62.
    Svensson, Linda
    et al.
    Södertörn University, School of Life Sciences, Biology.
    Mattsson, Jan-Eric
    Södertörn University, School of Life Sciences, Biology.
    Cooperation between botanical societies and academic institutions2005Conference paper (Other academic)
  • 63. Visram, Shakil
    et al.
    Yang, Ming-Che
    Pillay, Ruby Moothien
    Said, Sadri
    Henriksson, Oskar
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Grahn, Mats
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Chen, Chaolun Allen
    Genetic connectivity and historical demography of the blue barred parrotfish (Scarus ghobban) in the western Indian Ocean2010In: Marine Biology, ISSN 0025-3162, E-ISSN 1432-1793, Vol. 157, no 7, p. 1475-1487Article in journal (Refereed)
    Abstract [en]

    Studies on genetic connectivity are essential for the design of management strategies for coral reef fisheries. In this study we used a mitochondrial DNA marker to investigate population structure of the reef-associated parrotfish, Scarus ghobban, from four countries, Kenya, Mauritius, Seychelles and Tanzania, in the western Indian Ocean. We obtained nucleotide sequences of the mitochondrial control region for 117 individuals. Measures of haplotype diversity were relatively high. Pairwise population differentiation (F (ST)) was low, but not always non-significant. Analysis of molecular variance (AMOVA) showed genetic differentiation between groups, when the data was partitioned into two groups consisting of samples from Mauritius and Tanzania in one group, and samples from Kenya and Seychelles in another group. Direction of gene flow was estimated using a Bayesian approach. Migration was sometimes asymmetric or directional, coinciding with the flow of major oceanic and coastal currents in the region. Mismatch distributions, based on the observed number of differences among haplotype pairs, produced a unimodal distribution, indicative of recent demographic expansion. Phylogenetic analyses revealed three clades without any geographic structure, suggesting recent migration between historically isolated lineages. We reconstructed the historical demography of S. ghobban and examined it in the context of Pleistocene climate stages and changes in relative sea level. Overall, these results showed that populations of S. ghobban are genetically diverse and have relatively high gene flow, with some genetic structuring in the western Indian Ocean.

  • 64. Vladic, Tomislav
    et al.
    Forsberg, Lars A.
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Järvi, Torbjörn
    Sperm competition between alternative reproductive tactics of the Atlantic salmon in vitro2010In: Aquaculture, ISSN 0044-8486, E-ISSN 1873-5622, Vol. 302, no 04-mar, p. 265-269Article in journal (Refereed)
    Abstract [en]

    The maintenance of brood stock in appropriate conditions is an important equirement for the production of high quality offspring. In this study, e investigated fertility of the two life history forms of Atlantic almon males, precocious parr, brought up in breeding tanks in the atchery and anadromous, migratory searanched males, caught when eturning to the home river. The sperm quality was assessed by xperiments between equal amount of sperm from one adult and one parr ale in competition to fertilize eggs of a single female. The paternity as determined by a microsatellite analysis. Parr males achieved greater eproductive success than anadromous males under competition, and nadromous adults had greater fertility in controls as compared to the perm competition situation. In total, parr males achieved 3.6 times reater fertilization success than anadromous males. Sperm ATP content ontributed significantly to male fertility. Our results provide vidence that ejaculates of precociously mature Atlantic salmon parr are f increased quality as an adaptation to high sperm competition ntensity due to better maintenance in the fish farm than in the wild.

  • 65.
    Volkova, Kristina
    et al.
    Södertörn University, School of Life Sciences, Environmental science.
    Reyhanian, Nasim
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    Kot-Wasik, Agata
    Gdańsk University of Technology.
    Olsén, Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Porsch-Hällström, Inger
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Molecular biology.
    Hallgren, Stefan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Brain circuit imprints of developmental 17α-ethinylestradiol exposure in guppies (Poecilia reticulata): Persistent effects on anxiety but not on reproductive behaviour2012In: General and Comparative Endocrinology, ISSN 0016-6480, E-ISSN 1095-6840, Vol. 178, no 2, p. 282-290Article in journal (Refereed)
    Abstract [en]

    The effects of endocrine disruptors may vary with the timing of exposure. The physiological implications of adult exposure are present during and shortly after exposure while embryonic exposure can imprint changes manifested in adulthood. In this study, guppy (Poecilia reticulata) embryos were exposed to 2 ng/L and 20 ng/L of 17α-ethinylestradiol during development via the mother and reared in clean water from gestation until 6 months of age. As adults, fish exposed to 20ng/L during development showed significantly altered behaviour in the Novel Tank test, where anxiety is determined as the tendency to remain at the bottom upon introduction into an unfamiliar tank. 17α-ethinylestradiol treatment increased the latency time before swimming to the upper half of the tank and decreased the number of transitions to the upper half. In control females the basal stress behaviour responses were significantly higher than in males, as indicated by longer latency period and fewer and shorter visits to the upper half, supporting the importance of gonadal hormones for the behaviour. The anxiety increased, however, with treatment in both sexes, suggesting that the observed response is not entirely due to feminization of the males. Shoaling behaviour, analyzed as tendency to leave a shoal of littermates, was neither sex-differentiated nor changed by treatment. Also male reproductive behaviour, brain aromatase activity and testes histology, previously shown to respond to oestrogen exposure in adult guppy, were unaffected by the developmental treatment. This suggests that the stress system in the guppy is very sensitive to 17α-ethinylestradiol, which possibly causes an early organisational imprint on the brain circuit that regulates stress reactions.

  • 66. Wallin, Lotta
    et al.
    Svensson, Brita M.
    Lönn, Mikael
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Environmental science.
    Artificial dispersal as a restoration tool in meadows: Sowing or planting?2009In: Restoration Ecology, ISSN 1061-2971, E-ISSN 1526-100X, Vol. 17, no 2, p. 270-279Article in journal (Refereed)
    Abstract [en]

    Habitat fragmentation and the abandonment of former agricultural practices have led to extremely low dispersal rates for plant species growing in traditionally managed hay meadows in Sweden. Historically, seed dispersal between populations was maintained by hay movement, grazing animals, and farmers sharing their equipment. Because these means of dispersal typically are no longer occurring, artificial dispersal using seeds and plug-plants is tested here as a restoration tool. In this study, we chose two perennial herbs commonly occurring in meadows as test species, viz, Hypochoeris maculata L. (Asteraceae) and Succisa pratensis Moench. (Dipsacaceae). We found that plug-plant transplants were twice as effective as seed sowing for both species. The seed collection site was found to be important for seed-based establishment and survival; consequently, the choice of donor meadow is important when acquiring seeds used for restoration. We also found that survival of plants introduced as seeds was generally lower at sites harboring species favored by nitrogen as well as at sites in later successional phases. Both methods of introducing meadow species worked well, even though long-term establishment may well be more successful with the plug-plant method due to higher plug-plant establishment 2 years after introduction in the field.

  • 67.
    Wouters, Johanna
    et al.
    Södertörn University, School of Life Sciences, Environmental science.
    Janson, Sven
    Södertörn University, School of Life Sciences, Environmental science.
    Luskova, Vera
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Molecular identification of hybrids of the invasive gibel carp Carassius auratus gibelio and crucian carp Carassius carassius in Swedish waters2012In: Journal of Fish Biology, ISSN 0022-1112, E-ISSN 1095-8649, Vol. 80, no 7, p. 2595-2604Article in journal (Refereed)
    Abstract [en]

    Both mitochondrial DNA sequence and two nuclear microsatellite markers were used to confirm the identity of the first record of Carassius auratus gibelio in the western (Swedish) Baltic Sea region. A total of 49 fishes were analysed, where 22 were from three Swedish sites connected to the Baltic Sea. The D-loop mitochondrial DNA sequences showed that 16 of 22 Swedish fishes were related to C. a. gibelio. The phylogenetic analysis of these sequences showed that these fish are probably not native, but represent different lineages of C. a. gibelio from China, Japan and Russia. All except three of these 16 fishes had microsatellite alleles suggesting hybridization with Carassius carassius. These findings suggest that a cryptic invasion of C. a. gibelio might be in progress.

  • 68.
    Wouters, Johanna
    et al.
    Södertörn University, School of Life Sciences, Environmental science.
    Janson, Sven
    Södertörn University, School of Life Sciences, Environmental science.
    Olsén, K. Håkan
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Why didn’t we notice them earlier? The invasive fish Carassius gibelio(gibel carp) identified by genetic methods in Swedish waters.2011In: 7th International Conference on Marine Bioinvasions: Abstract Book, 2011, p. 162-Conference paper (Other academic)
  • 69.
    Wramner, Per
    et al.
    Södertörn University, School of Life Sciences, Coastal Management Research Center (COMREC). Södertörn University, School of Life Sciences, Environmental science.
    Nygård, Odd
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Från naturskydd till bevarande av biologisk mångfald: Utvecklingen av naturvårdsarbetet i Sverige med särskild inriktning på områdesskyddet2010Report (Other academic)
    Abstract [sv]

    Boken beskriver och analyserar utvecklingen av naturvårdsarbetet i Sverige under dess första sekel. Tonvikten ligger på områdesskyddet och de naturvetenskapliga, naturvårdsideologiska och naturvårdspolitiska grunderna för detta. Tyngdpunkten ligger på den senare delen av naturskyddets utveckling i Sverige, en period som hittills endast tilldragit sig begränsat forskningsintresse.

    I en kommande bok kommer skeendena i samband med införandet av EU:s naturvårdsdirektiv i Sverige att behandlas mer ingående.

    Download full text (pdf)
    Från naturskydd till bevarande av biologisk mångfald
    Download (jpg)
    presentationsbild
  • 70.
    Wramner, Per
    et al.
    Södertörn University, School of Life Sciences, Coastal Management Research Center (COMREC). Södertörn University, School of Life Sciences, Environmental science.
    Nygård, Odd
    Södertörn University, School of Life Sciences, Environmental science. Södertörn University, School of Life Sciences, Biology.
    Godset Almnäs i Norra Fågelås socken: natur- och naturvårdsförhållanden2012Report (Other academic)
    Download full text (pdf)
    Godset Almnäs i Norra Fågelås socken: natur- och naturvårdsförhållanden
    Download (jpg)
    presentationsbild
  • 71. Wrzaczek, Michael
    et al.
    Brosche, Mikael
    Salojarvi, Jarkko
    Kangasjarvi, Saijaliisa
    Idanheimo, Niina
    Mersmann, Sophia
    Robatzek, Silke
    Karpinski, Stanislaw
    Karpinska, Barbara
    Södertörn University, School of Life Sciences, Biology. Södertörn University, School of Life Sciences, Molecular biology.
    Kangasjarvi, Jaakko
    Transcriptional regulation of the CRK/DUF26 group of Receptor-like rotein kinases by ozone and plant hormones in Arabidopsis2010In: BMC Plant Biology, ISSN 1471-2229, E-ISSN 1471-2229, Vol. 10, p. 95-Article in journal (Refereed)
    Abstract [en]

    Background: Plant Receptor-like/Pelle kinases (RLK) are a group of onserved signalling components that regulate developmental programs and esponses to biotic and abiotic stresses. One of the largest RLK groups s formed by the Domain of Unknown Function 26 (DUF26) RLKs, also called ysteine-rich Receptor-like Kinases (CRKs), which have been suggested to lay important roles in the regulation of pathogen defence and rogrammed cell death. Despite the vast number of RLKs present in lants, however, only a few of them have been functionally haracterized. esults: We examined the transcriptional regulation of all Arabidopsis RKs by ozone (O(3)), high light and pathogen/ elicitor reatment-conditions known to induce the production of reactive oxygen pecies (ROS) in various subcellular compartments. Several CRKs were ranscriptionally induced by exposure to O(3) but not by light stress. (3) induces an extracellular oxidative burst, whilst light stress leads o ROS production in chloroplasts. Analysis of publicly available icroarray data revealed that the transcriptional responses of the CRKs o O(3) were very similar to responses to microbes or athogen-associated molecular patterns (PAMPs). Several mutants altered n hormone biosynthesis or signalling showed changes in basal and (3)-induced transcriptional responses. onclusions: Combining expression analysis from multiple treatments with utants altered in hormone biosynthesis or signalling suggest a model in hich O(3) and salicylic acid (SA) activate separate signaling pathways hat exhibit negative crosstalk. Although O(3) is classified as an biotic stress to plants, transcriptional profiling of CRKs showed trong similarities between the O(3) and biotic stress responses.

12 51 - 71 of 71
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • harvard-anglia-ruskin-university
  • apa-old-doi-prefix.csl
  • 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