1. |
- Boberg, Pelle, et al.
(författare)
-
The effect of high temperatures on seed germination of one native and two introduced conifers in Patagonia
- 2010
-
Ingår i: Nordic Journal of Botany. - Chichester : Wiley-Blackwell. - 0107-055X .- 1756-1051. ; 28:2, s. 231-239
-
Tidskriftsartikel (refereegranskat)abstract
- We examined the effect of thermal shock on the germination of seeds of three conifers, two introduced (Pseudotsuga menziesii and Pinus ponderosa), and one native to Patagonia (Araucaria araucana). Previous research has suggested increased susceptibility to invasions in burnt areas, and therefore, the effect of simulated fire (heat) on seed germination in these native and introduced species was compared. Seeds were heated to two different heat intensities (50°C and 100°C) for 1 or 5 min, which is within the temperature range reached in the upper soil layers during forest fires. Germination tests were then carried out in a growth chamber. The heat treatments had a negative effect on the germination of P. menziesii at temperatures of 100°C, and a negative effect on the germination of P. ponderosa at the temperature of 100°C and the exposure of 5 min. The heat treatments had no affect at all on A. araucana. The species with larger seeds (A. araucana) had higher survival rates after the thermal shocks. Also intraspecific differences in seed sizes possibly point at larger seeds surviving thermal shocks better than smaller seeds. In addition, thermal shock caused a delay in the onset of germination in the two introduced species, while it did not change the time for germination in A. araucana. © The Authors. Journal compilation © Nordic Journal of Botany 2010.
|
|
2. |
- Eneström, Johanna, et al.
(författare)
-
Partitioning of genetic variation in the weedy clonal herb Aegopodium podagraria (Apiaceae) in Sweden
- 2009
-
Ingår i: Nordic Journal of Botany. - Chichester : Wiley-Blackwell. - 0107-055X .- 1756-1051. ; 27:5, s. 437-443
-
Tidskriftsartikel (refereegranskat)abstract
- Although sexual reproduction appears to be rare in many clonal plant species, the majority of clonal species show similar levels of genetic variation to non-clonal plant species. Aegopodium podagraria is a noxious garden weed and has become a successful invader in many natural habitats. Earlier studies have demonstrated population differentiation in life-history traits between different A. podagraria populations in Sweden. In this study, we used three methods to assess genetic variation in this species. Using analyses of molecular markers (chloroplast DNA PCR-RFLP and allozyme electrophoresis) we did not detect any variation between different A. podagraria clones. However, a multivariate analysis of leaflet shape in five populations from central Sweden revealed considerable variation both within and between populations. The variation found in leaflet shape is suggested to be genetically based because the leaves were collected from plants grown from seed under similar conditions in a common garden environment. These relatively high levels of variation within and between populations indicate that there is likely to be repeated seedling recruitment within established populations. © The Authors. Journal compilation.
|
|
3. |
- Franzén, Markus, et al.
(författare)
-
Seed set differs in relation to pollen and nectar foraging flower visitors in an insect-pollinated herb
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:4, s. 274-283
-
Tidskriftsartikel (refereegranskat)abstract
- Assessing the relative contributions to seed sets of each of a plant species' floral visitors provides an indication of the relative influence of these visitors on the plants' reproductive success. In this study we compared the seed set of the gynodioecious Knautia arvensis (Dipsacaceae) in 49 local plant populations in two regions of southern Sweden. We measured the seed set for hermaphroditic and female plant individuals. In both plant sexes and both regions, the seed set was positively related to the abundance of Apidae. The seed set was negatively related to the abundance of pollen-foraging solitary bees (Halictidae, Megachilidae) and beetles (Oedemeridae, Malachidae). The seed set was not related to plant population size, plant density or female frequency. Our results confirm that pollination success in generalised plant-pollinator systems varies between pollinator groups. Flower-visitors foraging for pollen might not contribute to increased pollination success in generalised pollination systems.
|
|
4. |
- Hedrén, Mikael
(författare)
-
Plastid DNA haplotype variation in Dactylorhiza incarnata (Orchidaceae): evidence for multiple independent colonization events into Scandinavia
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:1, s. 69-80
-
Tidskriftsartikel (refereegranskat)abstract
- The early marsh orchid, Dactylorhiza incarnata (L.) Soo s. l., grows in medium-rich to rich fens and marshes over much of Europe and parts of Asia. The species is highly polymorphic and different forms may grow together at the same site. In the present study, I tested the hypothesis that these forms represent different migrant populations that have colonized Scandinavia independently of each other, possibly from different source areas. Accessions from Scandinavia and elsewhere were screened for variation at three size-variable plastid marker loci, one polyA repeat, one polyA-polyTA-polyT repeat and one 9 bp indel. Ten haplotypes were defined on basis on the combined variation pattern. The common occurrence of several haplotypes in southern Scandinavia and adjacent areas to the south and the east of the Baltic Sea suggests that D. incarnata has been dispersed on repeated occasions across the Baltic. Also, there was some correlation between haplotype composition and morphological form on the island of Gotland, in agreement with the independent colonization hypothesis. Material from northernmost Sweden, Finland and northwest Russia was fixed for a single widespread haplotype, indicating that populations in this area are located farther away from the Pleistocene refugia. Dactylorhiza incarnata ssp. lobelii from southwest Norway was characterized by a haplotype that was not encountered elsewhere in Scandinavia. Given its proximity to British populations dominated by the same haplotype, it is suggested that D. incarnata ssp. lobelii was established independently of the other Scandinavian populations, from coastal refugia located in western Europe.
|
|
5. |
- Jonsell, Bengt, et al.
(författare)
-
Nomenclatural notes to Flora Nordica Vol. 6 (Thymelaeaceae-Apiaceae)
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:2, s. 138-140
-
Tidskriftsartikel (refereegranskat)abstract
- The following names in Flora Nordica Vol. 6 are subject to nomenclatural action: Helianthemum oelandicum var. canescens (typified), Epilobium hornemannii (typified), Oenothera nuda (validated), Myriophyllum spicatum (emendation of typification), Viola rupestris subsp. relicta (typified), Hippophae rhamnoides (typified), Angelica archangelica subsp. littoralis (typified). - Flora Nordica Note no. 35.
|
|
6. |
- Kärnefelt, Ingvar
(författare)
-
Editorial
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:3, s. 165-165
-
Tidskriftsartikel (refereegranskat)abstract
- Abstract is not available
|
|
7. |
- Olofsson, Sofie, et al.
(författare)
-
Evolution, phylogeography and taxonomy of allopolyploid Dactylorhiza (Orchidaceae) and its implications for conservation
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:6, s. 548-556
-
Tidskriftsartikel (refereegranskat)abstract
- This review is based on recent molecular studies of Dactylorhiza (Orchidaceae). Most of the studies have focused on the allotetraploid members of the genus in general and on D. majalis ssp. lapponica in particular. It was concluded that most of the allotetraploid taxa have derived from hybridizations between the parental lineages D. maculata s.l. and D. incarnata s.l., with D. maculata s.l. serving as the seed parent. Evidence of multiple origins was found both among northern European allotetraploids as well as among Greek allotetraploids. Introgression from both parental lineages and hybridizations between independently derived polyploid lineages was also detected. The three morphologically similar taxa D. majalis ssp. traunsteineri, ssp. lapponica and ssp. russowii should be treated as one and most of the Greek allotetraploids should be regarded as regional variants of the southeastern European D. majalis ssp. cordigera. The Balkans and the Alps most probably served as refugia for the genus during the last glaciations and at least two waves of immigration reached Scandinavia. Finally, we suggest that the conservation of allotetraploid Dactylorhiza should emphasize important geographic areas and habitats and that the allopolyploids should have the same conservation status as the diploids.
|
|
8. |
- Pedersen, Henrik A. E., et al.
(författare)
-
On the distinction of Dactylorhiza baltica and D-pardalina (Orchidaceae) and the systematic affinities of geographically intermediate populations
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 28:1, s. 1-12
-
Tidskriftsartikel (refereegranskat)abstract
- The eastern European Dactylorhiza baltica (Klinge) N. I. Orlova and the western European D. pardalina (Pugsl.) Aver. (= D. praetermissa var. junialis (Verm.) Sengh) are usually considered to have non-overlapping geographic distributions, for which reason it has rarely been realized that they are morphologically similar. They have not previously been thoroughly compared by molecular methods, and no existing flora or revision has convincingly demonstrated that they can be distinguished by morphological characters. In reality, they might be 'political' rather than natural taxa. Prompted by the recent discovery of geographically intermediate populations (in eastern Denmark), originally identified as D. baltica, we have addressed this problem by analysis of morphometric data as well as molecular data from allozyme markers, plastid haplotypes, nuclear ITS alleles and nuclear microsatellites. Dactylorhiza baltica and D. pardalina turned out to be clearly distinguished genetically, and although they are morphologically similar, a few characters were identified that distinguish with 81-85% certainty between the two taxa. Molecular and morphometric data place the geographically intermediate populations in D. pardalina. Both taxa were confirmed to be allotetraploids combining diploid genomes from the D. incarnata s.l. and D. maculata s.l. lineages, and they should therefore be recognized as infraspecic taxa under D. majalis s.l. Thus, D. baltica should be called D. majalis subsp. baltica; D. pardalina is identical with D. praetermissa var. junialis, but the nomenclatural consequences for D. praetermissa, if treated as subspecies under D. majalis, are still unresolved.
|
|
9. |
- Ryde, Ulf
(författare)
-
Genetic analysis shows that Rubus vikensis is a distinct species with a disjunct distribution
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 28:2, s. 246-250
-
Tidskriftsartikel (refereegranskat)abstract
- Rubus vikensis A. Pedersen ex G. Wendt (sect. Corylifolii) was recently described from a restricted area in north western Scania, Sweden. In this investigation, I show that the same species occurs also on the Onsala peninsula in northern Halland and on a single locality in the middle of Halland. It has 35 chromosomes in all parts of the distribution area. Moreover, I show by random amplified polymorphic DNA (RAPD) analysis that R. vikensis is a distinct and well-defined species, clearly separated from the morphologically similar R. wahlbergii, with which it shares the chromosome number.
|
|
10. |
- Sandberg, Jakob, et al.
(författare)
-
Despite high uptake efficiency, non-mycorrhizal Rumex acetosella increases available phosphorous in the rhizosphere soil, whereas Viscaria vulgaris, Plantago lanceolata and Achillea millefolium does not
- 2009
-
Ingår i: Nordic Journal of Botany. - : John Wiley & Sons. - 0107-055X .- 1756-1051. ; 27:5, s. 444-448
-
Tidskriftsartikel (refereegranskat)abstract
- The phosphorous (P) uptake efficiency, reduction of the soil extractable P, and the root morphology was determined for the four common grassland species Rumex acetosella, Viscaria vulgaris, Plantago lanceolata and Achillea millefolium in one pot cultivation and one microcosm experiment. Rumex acetosella produced more than tree times as much biomass as each of V. vulgaris, P. lanceolata and A. millefolium, and could maintain a P concentration in the tissue that was twice as high as in the other species. R. acetosella was able to take up 10 times more phosphorous than the other species but the high uptake was not reflected in reduced Olsen P levels in the root affected soil. Calculating the uptake efficiency of the roots with a diameter less than 0.5 mm showed that the P uptake, calculated per root area, had been more efficient in R. acetosella than in the other species. The calculated rhizosphere volume (explored by the plant) seemed to correlate with the higher uptake efficiency of R. acetosella. We can conclude that R. acetosella have mechanisms to maintain a high P availability in the soil and may sustain a high uptake without any mycorrhizal interactions.
|
|
11. |
|
|
12. |
|
|
13. |
- Tyler, Torbjörn, et al.
(författare)
-
Hieracium (Asteraceae) of sub-alpine Dalarna, Sweden, revisited: decline in species richness attributable to both forestry and overgrowth
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:5, s. 419-424
-
Tidskriftsartikel (refereegranskat)abstract
- The Hieracium flora of westernmost Dalarna, comprising the southern fringe of the Scandes alps (central Scandinavia), is extremely rich in species. The area is dominated by species-poor coniferous sub-alpine and taiga forest, but within this matrix there are small and isolated sites with high species richness of both Hieracium and other plants. Both steep mountain slopes with outcrops of base-rich bedrock and moving ground water, and old seasonal or permanant human settlements constitute such biodiversity hotspots. However, today the former are threatened by modern forestry practices and/or exploitation for winter tourism and the latter are commonly abandoned and subjected to severe overgrowth or dramatically changed land-use. The area was thorougly surveyed in 1897-1921. In 2007, the same region and partly the same sites, were revisited. In 1897-1921, 15 Hieracium species were on average recorded from each site, but when the same sites were revisited in 2007 significantly fewer, only about 6 (40%) species per site, were refound. As far as the total species pool of the study area is concerned, it consisted of 168 species in 1897-1921, whereof only 117 (67%) were found in 2007. This remarkable reduction in species richness at both the local and the regional scale is attributable to both modern forestry practices and to the cessation of traditional agricultural practices like hay-making on semi-natural grasslands and extensive cattle-grazing in the forests. It is concluded that to reduce the on-going severe loss of biodiversity in the sub-alpine and taiga regions, conservation efforts in these areas ought to be enhanced and concentrated not only on saving what still remains of old-growth forest but also on managing remnants of grasslands and formerly grazed or mowed open forests around former settlements.
|
|
14. |
- Tyler, Torbjörn
(författare)
-
Lectotypifications and notes on the application of names of Hieracium sect. Hieracium, sect. Bifida and sect. Vulgata (Asteraceae) based on material from the province of Dalarna, central Sweden
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:1, s. 37-53
-
Tidskriftsartikel (refereegranskat)abstract
- Lectotypes are designated for 174 names of taxa described based on material from the Swedish province of Dalarna and accepted to belong to Hieracium sect. Hieracium, sect. Bifida and sect. Vulgata. The taxonomic and nomenclatural implications, i.e. taxonomic synonyms and infraspecific taxa not worthy of taxonomic recognition, of the lectotypifications are discussed. Three new combinations, H. mundulifolium (Johanss.) T. Tyler, H. oligasterum (Johanss. & Sam.) T. Tyler and H. transtrandense T. Tyler, are proposed to accommodate the infraspecific taxa H. gilvocaniceps Johanss. var. mundulifolium Johanss., H. expallidiforme (Dahlst. ex. Stenstr.) Dahlst. var. oligasterum Johanss. & Sam. and H. insuccatum Johanss. var. occidentale Johanss. & Sam. respectively, when treated at the rank of species.
|
|
15. |
- Tyler, Torbjörn, et al.
(författare)
-
Ploidy level analysis of apomictic Hieracium (Asteraceae) reveal unexpected patterns and variation.
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:6, s. 490-502
-
Tidskriftsartikel (refereegranskat)abstract
- The DNA ploidy level of 673 accessions belonging to 238 species of Hieracium have been analyzed by flow cytometry. 222 of the species were of Scandinavian origin as members of the exclusively apomictic H. sectt. Bifida, Hieracium, Oreadea, Tridentata and Vulgata. For the overwhelming majority of the species, the ploidy level (or chromosme number) has never been investigated before. Approximately 50 % of the Scandinavian species, previously believed to be exclusively triploid, were found to be tetraploid. In addition, two pentaploid samples, viz. H. intermarginatum Johanss. & Sam. from Sweden and H. cf. plumbeum Blytt & Fr. from Germany, were found. Although two or more accessions from geographically remote sites were analyzed for approximately 50 % of the Scandinavian species, only 2 (< 2 %) taxonomically undisputed species were found to consist of plants with more than one ploidy level. An intriguing pattern was revealed among Scandinavian members of H. sectt. Bifida and Vulgata when ploidy level and morphometric variation was compared, viz. the most typical or extreme representatives of these sections were found to be exclusively triploid whereas tetraploids dominate among species with intermediate morphology and among species morphologically intermediate between these sections and H. sect. Hieracium. This pattern may indicate that the tetraploids, which tend to have mainly northern distributions, have originated as the result of rare sexual hybridizations between triploid members of different sections, plausibly during or after the northward migration of the parental linages after the last glaciation. The results are believed to be highly relevant for understanding the processes of evolution and speciation within the predominantly apomictic genus Hieracium, but it is emphazised that additional data from e.g. molecular markers and pollen viability analysis are needed before any trustworthy conclusions can be made as far as evolutionary processes are concerned.
|
|
16. |
- Alatalo, Juha, 1966-
(författare)
-
Gender lability in trioecious Silene acaulis (Caryophyllaceae)
- 1997
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 17:2, s. 181-183
-
Tidskriftsartikel (refereegranskat)abstract
- Gender expression of individual cushions of Silene acaulis was shown to vary between years. Fifteen of thirty-nine (= 38%) cushions monitored changed gender expression between 1993 and 1995. Cushions dominated by female flowers were shown to be more stable in gender expression than cushions dominated by male or hermaphrodite flowers.
|
|
17. |
- Alatalo, Juha, 1966-, et al.
(författare)
-
Pollen viability and limitation of seed production in a population of the circumpolar cushion plant, Silene acaulis (Caryophyllaceae)
- 2001
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 21:4, s. 365-372
-
Tidskriftsartikel (refereegranskat)abstract
- Pollen viability among genders and limitation of female seed production in a natural trioecious population of the circumpolar cushion plant Silene acaulis was examined. Pollen viability was estimated by an in vitro pollen germination experiment. Both male and hermaphrodite flowers displayed large variation in pollen viability (0-53% in hermaphrodite and 0-54% in male flowers). There was a significant difference between genders in pollen viability: male plants had on average higher pollen viability than hermaphrodite plants. Resource and pollen limitation of seed production was studied by an experiment consisting of three treatments; (I) hand-pollination and removal of all other flowers on the cushion, (II) harid-pollination without removal of other flowers, and (III) open pollination without removal of flowers, Hand-pollination increased seed production, whereas removal of flowers had no effect on seed production. Abortion of pollinated ovules during seed development and seed mass did not differ among treatments. To control for effect of fruit number on seed production, data from naturally pollinated individuals was used. There was a positive correlation between both total number of seeds and fruit number, mean seed number per fruit and fruit number, respectively. These results indicate that seed production of S. acaulis is mainly limited by pollen availability whereas resource competition between fruits is not important as a limiting factor. The possible role of male quality differences between genders and pollen limitation of seed production for maintenance of trioecious reproductive systems is discussed.
|
|
18. |
- Altola, Juha, 1966-, et al.
(författare)
-
EFFECT OF ALTITUDE ON THE SEX-RATIO IN POPULATIONS OF SILENE ACAULIS (CARYOPHYLLACEAE)
- 1995
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 15:3, s. 251-256
-
Tidskriftsartikel (refereegranskat)abstract
- Predicted increase of female frequencies in gynodioecious Silene acaulis was tested along an altitude gradient in northern Sweden. Average female frequencies for the four sites increased with altitude from 42% to 59% within a short geographical distance. This follows the outcrossing hypothesis, that female frequencies should be positively correlated with selfing rates of hermaphrodites in populations. More adverse environmental conditions should favour gynodioecy in areas where reproduction to a greater part relies on vegetative reproduction or selfing. Further, a significant difference in corolla width was found between females and the larger hermaphrodites, but not between sites. Cushion size and the number of flowers per cushion decreased with altitude.
|
|
19. |
- Antonelli, Alexandre, 1978, et al.
(författare)
-
Pollination of the Lady's slipper orchid (Cypripedium calceolus) in Scandinavia - taxonomic and conservational aspects
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:4, s. 266-273
-
Tidskriftsartikel (refereegranskat)abstract
- The Lady's slipper orchid Cypripedium calceolus L. is considered one of the most beautiful orchids of Europe. Consequently, the species has suffered from over-collecting and is now critically endangered in many countries. Although pollination success is suspected to influence the long-term survival of Cypripedium calceolus, relatively little is known about the identity of its pollinators in mainland Sweden - a region that comprises the largest European populations. In order to identify which species pollinate eight representative populations in mainland Sweden, we observed and sampled visitors to flowers using a standardized protocol. Specimens were identified and any pollen smear found on their body was examined for the presence of Cypripedium pollen. Nine species were recognized as effective pollen vectors (Andrena cineraria, A. carantonica, A. haemorrohoa, A. helvola, A. nigroaenea, A. praecox, Colletes cunicularius, Lasioglossum fratellum and L. fulvicorne), four of them for the first time in Scandinavia. This is the first time that a species of Colletes is reported to carry pollen of Cypripedium in this region. All but one specimens were females. Our results suggest a taxonomically heterogeneous pollinator fauna for Cypripedium calceolus and are discussed in light of the management of this species.
|
|
20. |
- Bakker, Jan P., et al.
(författare)
-
Shading results in depletion of the soil seed bank
- 2014
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 32:5, s. 674-679
-
Tidskriftsartikel (refereegranskat)abstract
- 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.
|
|
21. |
- Cousins, Sara A. O., et al.
(författare)
-
Land use history and site location are more important for grassland species richness than local soil properties
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27, s. 483-489
-
Tidskriftsartikel (refereegranskat)abstract
- Lately there has been a shift in Sweden from grazing species-rich semi-natural grasslands towards grazing ex-arable fields in the modern agricultural landscape. Grazing ex-arable fields contain a fraction of the plant species richness confined to semi-natural grasslands. Still, they have been suggested as potential target sites for re-creation of semi-natural grasslands. We asked to what extent does fine-scale variation in soil conditions, management history and site location effect local plant diversity in grazed ex-arable fields. We examined local soil conditions such as texture, pH, organic carbon, nitrogen (N) and extractable phosphate (P) and effects on plant richness in ten pairs of grazed ex-fields and neighbouring semi-natural grasslands in different rural landscapes. Each grassland pair where in the same paddock. A multivariate test showed that site location and land use history explained more of differences in species richness than local soil property variables. Plant species richness was positively associated to grazed ex-fields with low pH, low N and P levels. Sites with high plant richness in semi-natural grasslands also had more species in the adjacent grazed ex-fields, compared to sites neighbouring less species-rich semi-natural grasslands. Although both soil properties and species richness were different in grazed ex-fields compared to semi-natural grassland, the site location within a landscape, and vicinity to species-rich grasslands, can override effects of soil properties. In conclusion, if properly located, ex-arable fields may be an important habitat to maintain plant diversity at larger spatio-temporal scales and should considered as potential sites for grassland restoration.
|
|
22. |
- Danilov, Roman, et al.
(författare)
-
Autumn phytoplankton assemblages in temperate lakes of different eutrophication level in the middle part of Sweden
- 2000
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 20:2, s. 225-232
-
Tidskriftsartikel (refereegranskat)abstract
- Phytoplankton assemblages were studied during autumn 1998 in oligo-, meso- and eutrophic lakes in central Sweden (62°54'N). Differences in phytoplankton assemblages have been detected both in space and time. In eutrophic lakes coccoid Chlorophyceae dominated quantitatively during September and October. Diatoms were the most diverse group in all types of lakes in September and in meso- and oligotrophic lakes in October. In November Cryptophyceae became the most abundant group in all lakes. The total richness of species decreased in the meso- and oligotrophic environments in November compared to September and October, whilst in the eutrophic environment it remained almost unchanged. Cluster analyses, using both presence-absence and presence-absence in combination with abundance matrices, showed similar results and a good resolution between the lakes of different eutrophication conditions. We conclude that the phytoplankton assemblages of the lakes studied depended on the trophic conditions and thus they can be used for resolution between different eutrophication levels.
|
|
23. |
- Grandin, Ulf, et al.
(författare)
-
Allozyme variation at a PGI locus in differently aged populations of Moehringia trinervia (Caryophyllaceae) in a successional area
- 2002
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 22:3, s. 303-311
-
Tidskriftsartikel (refereegranskat)abstract
- We studied genetic effects of the colonisation process during primary succession by analysing allozyme variation at a PGI locus in differently aged populations of Moehringia trinervia, which is a selfing annual with low dispersal ability. The populations studied come from islands and shores created in the 1880s by a drop in the water table of a Swedish lake and from old parts of a large island and of the mainland. The population age is known from five vegetation analyses over a century. We have also analysed the genetic composition of M. trinervia derived from seeds in the soil. Mainland populations had a higher genetic diversity than island populations that were little differentiated and differed genetically from the mainland populations. There was no temporal trend in the distribution of genetic variation on the new islands. The presence of alleles in the extant populations was associated with the proportion of that allele in the seed bank, indicating a main recruitment from the seed bank and not by repeated immigrations. We suggest that some of the new islands were colonised by a few early founders from the mainland. Later colonisation has occurred between adjacent islands, which preserves the founder effect and could explain the uniform, low genetic variation in the island populations
|
|
24. |
- Gustafsson, Susanne
(författare)
-
Flowering frequency in a small population of Gymnadenia conopsea : a five year study
- 2004
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 24:5, s. 599-605
-
Tidskriftsartikel (refereegranskat)abstract
- This investigation evaluates the usage of genetic markers, microsatellites, to distinguish and re-identify individual plants in a population of the orchid Gymnadenia conopsea. The study also illustrates the problem in estimating the size of a population from single year sampling as individuals can rest underground or occur in vegetative states; information extremely important for the understanding of population dynamics as well as providing information for conservation management. The total population size was, based on information from microsatellite loci, estimated to 84 individuals and vastly larger than the annual number of flowering plants (mean 31.4 individual s/year). Flowering frequency varied from 24-49%, 53 individuals flowered once, five individuals were flowering four years and a single individual was flowering five years. A common pattern was one or two flowering periods followed by a non-flowering period. The observed number of alleles and the observed and expected heterozygosity varied among loci, although allele frequencies and genotype frequencies did not vary significantly among years.
|
|
25. |
- Hjertson, Mats, 1966-, et al.
(författare)
-
Campylanthus hajarensis sp. nov. and a new record of Campylanthus (Scrophulariaceae) from Oman
- 2008
-
Ingår i: Nordic Journal of Botany. - 0107-055X .- 1756-1051. ; 26:1-2, s. 35-37
-
Tidskriftsartikel (refereegranskat)abstract
- Campylanthus hajarensis sp. nov. from a limestone gorge in the Hajar Mts in northern Oman, is described and illustrated. This is the first species of Campylanthus to be discovered in northern Oman. In addition, Campylanthus antonii, previously known only from Yemen, is recorded from the Dhofar Region in Oman.
|
|
26. |
- Johansson, Veronika A., et al.
(författare)
-
Dust seed production and dispersal in Swedish Pyroleae species
- 2014
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 32:2, s. 209-214
-
Tidskriftsartikel (refereegranskat)abstract
- Dust seeds are the smallest seeds in angiosperms weighing just about a few micrograms. These seeds are characteristic of most orchids, and several studies have been performed on seed features, fecundity and dispersal of orchid dust seeds. In this study we examine seed features, seed production and seed dispersal in another plant group with dust seeds, the Pyroleae (Monotropoideae, Ericaceae), focusing on six species: Pyrola chlorantha, P. minor, P. rotundifolia, Chimaphila umbellata, Moneses uniflora and Orthilia secunda. Seed production per capsule among these species was in the range between ca 1000 and 7800, and seed production per capsule bearing shoot was in the range between ca 7000 and 60 000. Combining our results with published information on pollen-ovule ratios suggests that these Pyroleae species have a generally efficient pollination system. The most fecund species was P. minor, the only species among the investigated that is probably largely self-pollinating. The investigated Pyroleae species have a seed production comparable to the less fecund orchid species. We studied seed dispersal in the field in one of the species, P. chlorantha. Despite the extremely small and potentially buoyant seeds, the vast majority of seeds are deposited close to the seed source, within a few meters. Further studies on the recruitment ecology of the investigated Pyroleae species are currently under way.
|
|
27. |
- Kullman, Leif
(författare)
-
Alpine flora dynamics : a critical review of responses to climate change in the Swedish Scandes since the early 1950s
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley-Blackwell. - 0107-055X .- 1756-1051. ; 28:4, s. 398-408
-
Tidskriftsartikel (refereegranskat)abstract
- Reports about changes of alpine plant species richness over the past 60 years in the Swedish Scandes are reviewed, synthesized and updated with data from recent reinventories. Methodologically, this endeavour is based on resurveys of the floristic composition on the uppermost 20 m of four high-mountain summits. The key finding is that the species pool has increased by 60-170% since the 1950s and later. Some of the invading species are new to the alpine tundra, with more silvine and thermophilic properties than the extant alpine flora. Not a single species of the original flora has disappeared from any of the summits. This circumstance is discussed in perspective of widespread expectations of pending temperature-driven extinction of alpine species in an alleged future warmer climate. These progressive changes coincided with distinct warming (summer and winter) since the late 1980s. During a short cooler period (1974-1994), the species numbers decreased and the upper elevational limits of some ground cover species descended. Thus, discernible responses, concurrent with both warming and cooling intervals, sustain a strong causal link between climate variability and alpine plant species richness. Methodologically, plot-less revisitation studies of the present kind are beset with substantial uncertainties, which may overstate floristic changes over time. However, it is argued here that carefully executed and critically interpreted, no other method can equally effectively sense the earliest phases of plant invasions into alpine vegetation.
|
|
28. |
- Kullman, Leif
(författare)
-
Recent cooling and dynamic responses of alpine summit floras in the southern Swedish Scandes
- 2014
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 32:3, s. 369-376
-
Tidskriftsartikel (refereegranskat)abstract
- Changes in plant species richness on alpine summits in the southern Swedish Scandes were analyzed between 2004/2006 and 2012. This period experienced consistent summer and winter cooling and finalized with a cold and snow rich summer 2012. Re-surveys of these summits had previously documented substantial increases in species numbers in concordance with climate warming since the mid-20th century. Over the present study period, species richness decreased by 25-46%. The majority of lost species were those that had advanced upslope during the previous warm episode. Cooling since the mid 2000s and particularly the unusually short and snow-rich growth period in 2012 caused a floristic retrogression. Taken together with extensive upshifts of many species during previous relative warm decades, recent downshifts highlight the large capability of certain alpine species to track their ecological niches as climate changes. The pivotal importance of unusually late-lying snow in 2012, suggests that snow cover phenology exerts a more direct effect on the composition of the alpine flora than ambient temperatures. Dynamic modeling of future ecological landscape evolution needs to consider episodes of the kind reported here.
|
|
29. |
- Köchy, Martin, et al.
(författare)
-
Biogeography of vascular plants on habitat islands, peninsulas and mainlands in an east-central Swedish agricultural landscape
- 1997
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 17:2, s. 215-223
-
Tidskriftsartikel (refereegranskat)abstract
- The increase of island species richness with area can be explained by an increase in habitat diversity or by an equilibrium of species immigration and extinction. We examined vascular plant species richness in 39 sites (24 habitat islands, 7 ‘habitat peninsulas’ and 8 comparable ‘mainland’ sites). We sampled at three scales: whole sites, meadows within sites and quadrats (4 m × 4 m) within meadows. All sites (10–104 m2) contained natural vegetation within arable fields in eascentral Sweden. There was a strong correlation between species richness and area for whole sites and for meadows There was no correlation, however, between species richness in quadrats and site area. The difference between site and meadow results on one side and quadrat results on the other suggests that species richness increases with whole site area primarily because large sites are more diverse than smaller ones. Speciearea relationships did not differ between islands, peninsula and mainland sites. Thus, patterns of species richness on our sites were more consistent with habitat diversity than an immigratioextinction equilibrium.
|
|
30. |
- Lidén, Magnus, 1951-, et al.
(författare)
-
Studies in Dactylicapnos (Papaveraceae-Fumarioideae) part II. Revision of Dactylicapnos sect. Pogonosperma sect. nov., with D. arunachalensis sp. nov.
- 2014
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 32:2, s. 176-184
-
Tidskriftsartikel (refereegranskat)abstract
- Dactylicapnos sect. Pogonosperma Liden & M. K. Pathak sect. nov. is established and revised based on morphology, and found to include four species: D. gaoligongshanensis from west Yunnan, D. arunachalensis Liden & M. K. Pathak sp. nov., endemic to central Arunachal Pradesh, D. grandifoliolata (syn. D. ventii) and D. paucinervia (K. R. Stern) Liden & M. K. Pathak comb. nov., the two latter species widespread in the east Himalayas.
|
|
31. |
- Lidén, Magnus, 1951-
(författare)
-
Three new species of Dactylicapnos (Fumariaceae) and a synopsis of the D. macrocapnos complex
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 28:6, s. 656-660
-
Tidskriftsartikel (refereegranskat)abstract
- The Dactylicapnos macrocapnos complex is revised, and D. platycarpa Liden, D. odontocarpa Liden and D. macrocapnos subsp. echinosperma Liden are recognised as new taxa. The complex consists of a chain of 4 vicariant taxa from northwestern India (Garhwal) to western Bhutan (Thimphu). Dactylicapnos cordata Liden (eastern Nepal, Darjeeling) is described and contrasted with its close relative, the geographically disjunct D. burmanica (western Yunnan, Burma).
|
|
32. |
- Lättman, Håkan, et al.
(författare)
-
Changes in the distributions of epiphytic lichens in southern Sweden using a new statistical method
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:5, s. 413-418
-
Tidskriftsartikel (refereegranskat)abstract
- Past studies on changes in species distribution have mainly been based on analysis of range boundaries. In contrast, the method used here evaluates shifts in species geographic centroids within a predefined area. We used presence/absence data on epiphytic lichens collected 1986 and 2003 from 64 sites in southern Sweden. A centroid was calculated each year, for each lichen species and substrate. The distance of centroid movement was evaluated in a permutation procedure. In total, 56 lichen species on 22 tree species were involved in the analyses, yielding 30 cases that had sufficient sample sizes both years to be evaluated. Out of these, three exhibited a significant movement of their centroid. The shift of lichen centroids of Hypogymnia physodes (L.) Nyl. and Vulpicida pinastri (Scop.) J.-E. Mattsson andamp; M. J. Lai on the tree species Juniperus communis L. was 50 and 151 km with the direction 27 degrees and 48 degrees, respectively. For Hypogymnia physodes on Pinus sylvestris L., corresponding values were 41 km and 30 degrees. The northnortheast shifts of these species in Sweden could be a response to a warming climate.
|
|
33. |
- Lättman, Håkan, et al.
(författare)
-
Decline in lichen biodiversity on oak trunks due to urbanization
- 2014
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 32:4, s. 518-528
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Biodiversity often suffers from urbanization. In the present study, we focused on how the duration of urbanization affects the richness of 17 epiphytic lichen species and their cover on large oaks in urban environments in a city of 100 000 inhabitants in southeast Sweden. We also surveyed trees in adjacent rural areas, selected to have similar distributions of tree trunk circumference and surrounding oak density (within 300 m). Lichen richness and cover were lower on urban trees compared to rural trees. Furthermore, richness and cover decreased with the length of time that urban trees had been surrounded by houses. Most of the species that were analysed demonstrated a decline in occurrence with respect to the duration of housing development. The reduction in the probability of occurrence varied from 60% (Calicium viride, Evernia prunastri), 80% (Chrysothrix candelaris) to 90% (Ramalina spp.) during the considered 160-year period of urbanization. Therefore, even if valuable trees survive over the course of development, their lichen biota is likely to become depleted over time. © 2014 The Authors.
|
|
34. |
- Maad, Johanne, 1970-, et al.
(författare)
-
Floral size variation in Campanula rotundifolia (Campanulaceae) along altitudinal gradients : patterns and possible selective mechanisms
- 2013
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 31:3, s. 361-371
-
Tidskriftsartikel (refereegranskat)abstract
- We investigated patterns of flower-size variation along altitudinal gradients in the bee-pollinated perennial Campanula rotundifolia (Campanulaceae) by examining 22 Norwegian populations at altitudes between 240 and 1100 m a.s.l. We explored potential mechanisms for the underlying pattern by quantifying pollinator-faunal composition, pollinator-visitation rates and pollen limitation of seed set in subsets of the study populations. Despite a decrease in plant size, several measures of flower size increased with elevation. Bumble bees were the main pollinators at both alpine and lowland sites in the study area. However, species composition of the pollinator fauna differed, and pollinators were larger in higher-elevation than in lower-elevation sites. Pollinator visitation rates were lower at higher-elevations than at lower elevations. Pollen limitation of seed set did not vary significantly with altitude. Our results are consistent with differences in bumble-bee size and visitation rates as causal mechanisms for the relatively larger flowers at higher elevations, in three non-mutually exclusive ways: 1) Larger flowers reflect selection for increased attractiveness where pollinators are rare. 2) Larger and fewer flowers represent a risk avoidance strategy where the probability of pollination is low on any given day. 3) Flower size variation reflects selection to improve the fit of pollinators with fertile structures by matching flower size to pollinator size across sites.
|
|
35. |
- Moberg, Roland
(författare)
-
The lichen genus Heterodermia (Physciaceae) in South America - a contribution including five new species
- 2011
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 29:2, s. 129-147
-
Tidskriftsartikel (refereegranskat)abstract
- Thirty-three species of the lichen genus Heterodermia in South America, mainly from Ecuador and Peru, are defined. Morphology, anatomy, chemistry, habitat, distribution and interrelation between the species are discussed. A key to the treated species is presented. Five species are described as new; Heterodermia andina, H. arvidssonii, H. badia, H. fertilis and H. parva. One new combination is proposed; H. spinigera. Two species are reported as new to South America, H. spathulifera and H subcitrina, and H. palpebrata is reported as new to USA.
|
|
36. |
- Mouly, Arnaud, et al.
(författare)
-
Paederia ntiti sp nov (Rubiaceae) from the Comoros and notes on the affinities of Comorian rubiaceous climbers and lianas
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 28:3, s. 262-266
-
Tidskriftsartikel (refereegranskat)abstract
- A new species of Paederia L. (Rubiaceae, Rubioideae, Paederieae), P. ntiti Mouly & Puff, endemic to the Comoros (Grande Comore, Anjouan and Mayotte) and occurring in natural elevated forests is described and illustrated. Its conservation status is evaluated and the species is rated 'Endangered' (EN). A key to the Paederia taxa of the Comorian archipelago is provided. Also included are notes on the three other species of rubiaceous climbers and lianas known from the Comoros: Paederia bojeriana (A. Rich. ex DC.) Drake, Danais comorensis Drake and Uncaria africana G. Don.
|
|
37. |
|
|
38. |
- Savic, Sanja, et al.
(författare)
-
The lichen genus Henrica (Verrucariaceae, Eurotiomycetes) in northern Europe
- 2008
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 26:3-4, s. 237-247
-
Tidskriftsartikel (refereegranskat)abstract
- In a previous three gene phylogeny study (nuITS rDNA, nuLSU rDNA and RPB1 region A-D) a well supported clade, most closely related to Verrucaria rupestris and also close to Sporodictyon and Atla, was found. Here this clade is identified as Henrica. A phylogeny of these genera based on the nuITS rDNA is supplied, and also a key to crustose species in Verrucariaceae with large, brown muriform spores. Based on material from northern Europe, Henrica is emended to include H. theleodes and H. melaspora, both new combinations in the previously monotypic genus. Verrucaria theleodes and V. scotinospora are lectotypified.
|
|
39. |
- Ståhl, Bertil, 1957-
(författare)
-
Four new species and new records of Symplocos (Symplocaceae) from Peru and Bolivia, and a key to all species of Symplocos known to occur in Ecuador, Peru and Bolivia
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 28:1, s. 79-87
-
Forskningsöversikt (refereegranskat)abstract
- Four new species of Symplocos (Symplocaceae) are described from montane forests in Peru. Symplocos cuscoënsis Ståhl (from Dept Cusco) is distinguished inter alia by enlarged floral bracts and anthers that are longer than wide, S. excoriata Ståhl (Dept Amazonas and Cajamarca) by the exfoliating bark on young shoots, S. serratifolia Ståhl (Dept Cajamarca and Cusco) by tomentulose young shoots and lower leaf surfaces as well as long petioles, and S. trichocarpa Ståhl (Dept Cajamarca) by its tuberculate young shoots and pilose fruits. Symplocos guianensis (Aubl.) Gürke is reported as new to Bolivia and S. nitens (Pohl) Benth. is reported as new to Bolivia and Peru. A key to all 67 species of Symplocos known from Ecuador, Peru and Bolivia is provided.
|
|
40. |
- Ståhl, Bertil, 1957-
(författare)
-
Tropaeolum sparrei sp. nov. (Tropaeolaceae) from western Ecuador
- 2010
-
Ingår i: Nordic Journal of Botany. - Copenhagen : Council for Nordic Publications in Botany. - 0107-055X .- 1756-1051. ; 28:3, s. 321-323
-
Tidskriftsartikel (refereegranskat)abstract
- A new species, Tropaeolum sparrei Ståhl (Tropaeolaceae), is described from submontane cloud forest habitat in western Ecuador. It differs from T. papillosum Hughes (the species it resembles most) by having thinner, tomentose stems, smaller, glabrous or subglabrous leaves with the petiole inserted relatively closer to the lower leaf margin, and flowers with uniformly coloured and straight calyx spurs. In leaf shape it is also similar to T. repandum Heilborn, from which it differs in its larger flowers with entirely black petals and blue anthers.
|
|
41. |
- Ståhl, Bertil, 1957-, et al.
(författare)
-
Zygia nubigena sp. nov. (Leguminosae–Mimosoideae) from a submontane cloud forest in western Ecuador
- 2010
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 28:4, s. 453-456
-
Tidskriftsartikel (refereegranskat)abstract
- A new species, Zygia nubigena Ståhl, L. Rico & G. P. Lewis (Leguminosae–Mimosoideae), is described from western Ecuador. It is characterized by large and very thick-walled fruits with coarsely alveolate-reticulate surfaces, spicate inflorescences, one (less common) or two pairs of pinnae per leaf and 4 or 5 pairs of petiolulate leaflets per pinna. In leaf features, Z. nubigena is similar to Z. steyermarkii (Schery) Barneby & J. W. Grimes from montane forest in southern Ecuador, but differs by having somewhat smaller flowers borne in long, many-flowered racemes (not 25–30-flowered capitulae). The fruits of Z. nubigena resemble those of Z. rhytidocarpa L. Rico (Honduras, Guatemala) and Z. megistocarpa (Barbosa) L. Rico (northern Peru), but Z. nubigena differs from both in vegetative and floral characters.
|
|
42. |
- Tekle, Kebrom, et al.
(författare)
-
Vegetation on hill slopes in southern Wello, Ethiopia : Degradation and regeneration
- 1997
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 17:5, s. 483-493
-
Tidskriftsartikel (refereegranskat)abstract
- A study was made of the vegetation in southern Wello (Ethiopia) in relation to human impact and the environment. 65 sample plots were laid out and analysed with respect to the cover value of vascular plant species. Altitude, slope, aspect and estimates of grazing pressure for each plot were also recorded along with physical and chemical soil properties analysed for samples taken from each plot. The following environmental factors, isolated by forward selection, show correlation with the axes of Canonical Correspondence Analysis (CCA): altitude, grazing, pH, K, Ca, Mg, slope and aspect.Through hierarchical and non-hierarchical clustering methods the vegetation was divided into eight types, from which one was secondary forest characterised by patch dominance of Juniperus procera and Olea europaea ssp. cuspidata. These forest patches are found at high altitude sites and because of their inaccessibility are usually characterised by low livestock density and consequently low grazing pressure. The presence of large boulders and stones in Podocarpus falcatus forest decreases accessibility and creates natural protection for the trees. The other vegetation types, most of which are found at lower altitude and associated with varying intensities of grazing, include grasslands (grazed and protected), regenerating sites dominated by Euclea racemosa and Dodonaea angustifolia, dense and open shrublands and Olea europaea ssp. cuspidata woodlands. Human interference has a major impact on the vegetation of the study area and its recovery will depend on the degree of participation of the local people.
|
|
43. |
- Thulin, Mats
(författare)
-
A new genus of Sapindaceae from Somalia
- 2004
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 24:5, s. 509-511
-
Tidskriftsartikel (refereegranskat)abstract
- The new genus Hirania (Sapindaceae), with the single species H. rosea from south-central Somalia, is decribed and illustrated. It is a shrub with simple, entire leaves, alternate or crowded on short-shoots, and without stipules. The inflorescences are branched with monochasially arranged, unisexual flowers. The flowers (only male ones known) are zygomorphic with five sepals with gland-tipped hairs along margins, four pink, subequal, clawed petals without appendages, and eight, glabrous stamens. The dark purple disk is narrow and tubular and consists of an upper broader segment partly enclosing a lower narrower segment. The closest relative is believed to be the Australian genus Diplopeltis.
|
|
44. |
- Thulin, Mats
(författare)
-
A new species of Atriplex (Chenopodiaceae) from Somalia
- 2004
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 24:5, s. 507-508
-
Tidskriftsartikel (refereegranskat)abstract
- Atriplex erigavoensis, a new species from gypsum silt in northern Somalia, is described and illustrated. It is distinctive particularly by the dorsal appendages of the female bracteoles that look like an extra pair of small bracteoles.
|
|
45. |
- Thulin, Mats, 1948-
(författare)
-
Acacia fumosa sp. nov. (Fabaceae) from eastern Ethiopia
- 2008
-
Ingår i: Nordic Journal of Botany. - 0107-055X .- 1756-1051. ; 25:5-6, s. 272-274
-
Tidskriftsartikel (refereegranskat)abstract
- The new species Acacia fumosa is described and illustrated. It is confined to the Somali National Regional State (Ogaden) in eastern Ethiopia, where it is dominant and widespread on limestone hills in an area of at least 8 000 km2. Acacia fumosa is closely related to A. ochracea in south-western Somalia, but differs, for example, in its ash grey, smooth and non-flaking bark, densely pubescent leaves, and pink flowers.
|
|
46. |
- Thulin, Mats, 1948-
(författare)
-
Aloe nugalensis sp. nov. (Asphodelaceae), a new gypsum endemic from northeastern Somalia
- 2012
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 30:6, s. 729-731
-
Tidskriftsartikel (refereegranskat)abstract
- The new species Aloe nugalensis Thulin, a shrubby plant with long, drooping leaves and a drooping, branched inflorescence with long-pedicellate orange red flowers, is described from a gypsum hill in the Nugaal valley of northeastern Somalia. The only known material is an individual grown in the Botanical Garden of Uppsala University from seeds collected in Nov 1985 that first flowered in Feb 2011.
|
|
47. |
- Thulin, Mats, 1948-, et al.
(författare)
-
Ambilobea, a new genus from Madagascar, the position of Aucoumea, and comments on the tribal classification of the frankincense and myrrh family (Burseraceae)
- 2008
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 26:04-mar, s. 218-229
-
Tidskriftsartikel (refereegranskat)abstract
- Phylogenetic analyses of 46 species, representing all tribes and 14 out of 18 recognized genera of Burseraceae, are performed using nuclear ETS and plastid rps16 sequences. Boswellia madagascariensis, the only Malagasy species of this genus, is shown to belong to a clade comprising all sampled members of the current tribe Canarieae plus Triomma, whereas other species of Boswellia (including the type, B. serrata) form a clade that is strongly supported as sister to Garuga. A new genus, Ambilobea, is proposed for B. madagascariensis and the new combination A. madagascariensis is made. Ambilobea differs from Boswellia s. s. by being dioecious and by having valvate petals and, furthermore, is unique in the family by its winged tips to the petioles, by having pyrenes that remain attached to the detached valves of the fruit at dehiscence, and by its long-spinose pollen grains. Aucoumea, a monotypic central African rain forest genus, is strongly supported as sister to a clade with the arid-adapted Bursera and Commiphora. Boswellia s. s. and Garuga form a clade characterized by having hermaphroditic flowers. The relationships within Burseraceae emerging from this and previous phylogenetic studies are, on several points, in conflict with current tribal delimitation. The following suggestions for a new tribal classification of Burseraceae are made: 1) Beiselia, sister to the rest of the family, needs to be placed in a tribe of its own, Beiselieae, trib. nov., 2) Protieae should be restricted to Crepidospermum, Protium and Tetragastris, although generic rearrangements seem to be needed within this tribe, 3) Bursereae should be restricted to Aucoumea, Bursera and Commiphora, but generic rearrangements are needed in the Bursera-Commiphora complex, 4) the remaining genera, Ambilobea, Boswellia, Canarium, Dacryodes, Garuga, Haplolobus, Pseudodacryodes, Rosselia, Santiria, Scutinanthe, Trattinnickia and Triomma, are probably best placed in a broadly circumscribed Garugeae.
|
|
48. |
- Thulin, Mats
(författare)
-
Expansion of Crabbea (Acanthaceae) and the description of two new species from Somalia
- 2004
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 24:5, s. 501-506
-
Tidskriftsartikel (refereegranskat)abstract
- Crabbea is expanded to include the monotypic Golaea and Acanthostelma, both endemic in northern Somalia. The new combinations C. migiurtina (=Golaea migiurtina) and C. thymifolia (=Acanthostelma thymifolium) are made and the names are lectotypified. The new species C. pinnatifida and C. albolutea, both endemic in Somalia, are described and illustrated.
|
|
49. |
- Thulin, Mats
(författare)
-
New species of Tephrosia (Fabaceae) from Somalia and Yemen
- 2004
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 24:5, s. 513-517
-
Tidskriftsartikel (refereegranskat)abstract
- The new species Tephrosia flava, from limestone areas in north-eastern Somalia, and T mahrana, from wadis in the deserts of south-eastern Yemen, are described and illustrated.
|
|
50. |
- Thulin, Mats, 1948-
(författare)
-
Salvia geminata sp. nov. with remarkable stamen arrangement from southern Yemen, with notes on S. areysiana (Lamiaceae)
- 2009
-
Ingår i: Nordic Journal of Botany. - : Wiley. - 0107-055X .- 1756-1051. ; 27:4, s. 336-338
-
Tidskriftsartikel (refereegranskat)abstract
- The new species Salvia geminata, a dwarf shrublet from rocky coastal slopes of the Mahrah Region in Yemen, is described and illustrated. A remarkable feature of the species is that the upper thecae of the stamens are inflexed and connate, a condition that seems to be previously unknown in the genus. The apparently closely related S. areysiana, previously known only from the area of Jebel Areys in the Abyan Region, is reported also from the Hadramaut Region
|
|