| 1. |
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| 2. |
- Bisang, Irene, et al.
(författare)
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Can the meiotic sex ratio explain the sex ratio bias in adult populations in the dioicous moss Drepanocladus lycopodioides?
- 2017
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Ingår i: Journal of Bryology. - : Informa UK Limited. - 0373-6687 .- 1743-2820. ; 39:2, s. 115-120
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Tidskriftsartikel (refereegranskat)abstract
- Sex ratio variation is commonly observed in natural populations of many organisms with separate sexes and genetic sex determination, including bryophytes. Most bryophyte populations exhibit female-skewed expressed adult sex ratios, generally inferred from counts of sexually mature plants. For the rarely sexually reproducing perennial dioicous moss Drepanocladus lycopodioides, we showed that a female bias also exists in the genetic adult sex ratio, using a specifically designed molecular sex-associated marker. Here, we investigated whether the meiotic spore sex ratio contributes to the observed bias in genetic adult sex ratio in natural populations. Earlier attempts to study meiotic sex ratios have involved commonly cultivated ruderals that rapidly express sex in the laboratory. We established single-spore cultures from field-collected sporophytes from these populations and used the marker to assess the sex of individual sporelings. Spore germinability was (near) complete, and mortality among sporelings was virtually absent. The true meiotic sex ratio did not differ from equality, but strongly differed both from the observed genetic sex ratios in the natural adult populations, and from the European scale genetic sex ratio. We conclude that the biased population sex ratios in this species arise at life cycle stages after spore germination. Sexual dimorphism may selectively favour female proliferation during some phase of gametophyte development. Based on methodological progress, we successfully used a perennial study species with rare sexual reproduction, which significantly broadens the life history spectrum investigated in bryophyte sex ratio studies.
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| 3. |
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| 4. |
- Bu, Zhaojun, et al.
(författare)
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Performance of four mosses in a reciprocal transplant experiment : implications for peatland succession in NE China
- 2013
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Ingår i: Journal of Bryology. - 0373-6687 .- 1743-2820. ; 35, s. 220-227
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Tidskriftsartikel (refereegranskat)abstract
- Sphagnum dominates the moss layer in northern peatlands, but its dominance has decreased while there has been an expansion of other moss genera in some peatlands of NE China since the 1960s. To discover the mechanisms underlying this succession, we performed a four-month reciprocal transplant experiment in Hani Peatland with three Sphagnum species, Sphagnum palustre, S. magellanicum, and S. fuscum and one other moss Polytrichum strictum. Performance of the four mosses and the environmental factors: height above water table (HWT), vascular plant cover and pH, electrical conductivity, base cations, and N and P concentrations in water in the four moss habitats were measured. Biomass production in S. palustre was negatively affected by HWT. Phosphorus had a positive effect on biomass production in S. magellanicum and Polytrichum. None of the environmental factors had any effect on S. fuscum. Overall, the three Sphagnum species deteriorated in P. strictum hummocks, while P. strictum exhibited a wider ecological amplitude and maintained or increased its vigour levels in Sphagnum hummocks. Biomass production in S. palustre and S. magellanicum was negatively affected by P. strictum indicating the competitive ability of P. strictum. Our results suggest that its wide ecological amplitude and competitive ability may explain why P. strictum can expand and replace Sphagnum in some northern peatlands.
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| 5. |
- Callaghan, D. A., et al.
(författare)
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Geographic range and population size of the habitat specialist Codonoblepharon forsteri in a changing climate
- 2022
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Ingår i: Journal of Bryology. - 0373-6687 .- 1743-2820. ; 44:1, s. 35-40
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Codonoblepharon forsteri is a rare epiphytic moss characteristically associated with water-filled holes in trees. This study aims to review its range and population and assess effects of climate change.Methods: An inventory of sites from where C. forsteri has been recorded was compiled. Extent of Occurrence (EOO) and Area of Occupancy (AOO) were calculated. Population size was estimated, using an occupied tree as an ‘individual-equivalent’ of the moss. Climatic conditions of its current distribution were characterised, and an ensemble model of its distribution generated. The latter was projected onto present and future climatic layers.Results: C. forsteri has been recorded from 205 sites in 18 countries, in Europe, N Africa and SW Asia. It has been undergoing an overall decline. Most sites have few occupied trees, and a world population of 1000–10,000 individual-equivalents is estimated. Model projections suggest the species will experience a range increase of +0.27–0.78 by 2050 and +0.34–0.97 by 2070, especially in the NW, in particular across France and the UK. Range loss is predicted to be -0.16–0.23 in 2050 and -0.18–0.32 in 2070, affecting the driest areas of the current range around the Mediterranean, especially in N Africa.Conclusions: C. forsteri has a relatively large EOO but a relatively small AOO, likely the product of its habitat specialism. A major reason for recent declines appears to be widespread abandonment of traditional ‘pollarding’ of trees. The potential climatic range of the species will shift significantly northwards over the next few decades
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| 6. |
- Campbell, Charles, 1982-, et al.
(författare)
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The effects of winter stress on Sphagnum specieswith contrasting macro- and microdistributions
- 2019
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Ingår i: Journal of Bryology. - : Taylor & Francis. - 0373-6687 .- 1743-2820. ; 41:3, s. 205-217
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Tidskriftsartikel (refereegranskat)abstract
- Introduction: Sphagnum L. forms much of the ground cover in northern peatlands. Different species show affinities for bioclimatic regions in Europe (oceanic/continental; northern/southern) and species-specific tolerance of winter conditions can be a factor explaining their distribution.Methods: We focussed on low temperature in a series of experiments and tested (1) the innate ability of a selection of Sphagnum species to tolerate low temperature in relation to their micro-topographic (wetness) and geographical (climate) distribution; (2) the rate of cold tolerance acquisition; and (3) the ability of species to survive a range of low temperature once cold hardened.Key results: Our experiments showed that maximal PSII efficiency (Fv/Fm, chlorophyll fluorescence), growth rates and survival were all negatively affected by sub-zero temperatures. Environmental conditions associated with the onset of winter (colder nights and shorter days) triggered the acquisition of cold tolerance in Sphagnum.Conclusions: The results were not unequivocal, but species associated with colder climates were generally more tolerant of sub-zero conditions. Species associated with the wettest and driest ends of the wetness gradient were more consistent in their responses than those in between, with wetter-dwelling species being less sensitive to sub-zero temperature than species found in drier microhabitats. Overall, our results suggest that adaptation to winter conditions contribute to the current distribution patterns of Sphagnum species.
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| 7. |
- Cronberg, Nils, et al.
(författare)
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Clonal distribution, fertility and sex ratios of the moss Plagiomnium affine (Bland.) T.Kop. in forests of contrasting age
- 2003
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Ingår i: Journal of Bryology. - : Informa UK Limited. - 1743-2820 .- 0373-6687. ; 25, s. 155-162
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Tidskriftsartikel (refereegranskat)abstract
- Six populations of the clonal forest floor moss Plagiomnium affine from forests of different age were screened for genetic variation at 23 allozyme loci, of which nine were polymorphic. Samples consisting of two adjacent unconnected shoots were taken at regular intervals along one transect from each population. A total of 602 shoots was analysed. Almost 80% of the shoots were sterile (i.e. not expressing male or female gender). Sex remained unknown for only 10% of shoots after identification of genets based on electrophoretic data. We identified a mean number of 3.7 fertile clones per population. The mean length of clones along transects in each population ranged between 2 and 3 in. The size distribution within populations was bimodal, with a few dominant clones and a varying number of much smaller clones. The overall sex ratio was slightly female biased at the ramet level, but balanced at the genet level. Forest age was negatively correlated with percentage of sterile shoots and positively correlated with frequency of sporophytes. In both cases correlations were significant only if population 1, which was subject to extreme soil disturbance by badgers, was excluded. We conclude that the effective population size is larger, and the susceptibility to genetic drift is lower, in old forests.
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| 8. |
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| 9. |
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| 10. |
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| 11. |
- Gradstein, S. R., et al.
(författare)
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Riccardia verticillata Gradst. & Reeb, a new dendroid species of Riccardia (Aneuraceae) from the Cordillera del Condor, Ecuador
- 2019
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Ingår i: Journal of Bryology. - : Informa UK Limited. - 0373-6687 .- 1743-2820. ; , s. 322-327
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Tidskriftsartikel (refereegranskat)abstract
- Introduction. The Cordillera del Condor on the border between Ecuador and Peru stands out because of its rich biodiversity and high endemism. Here we describe a new dendroid species of the thalloid liverwort genus Riccardia, R. verticillata Gradst. & Reeb, from El Quimi Biological Reserve in the Condor region of Ecuador. Methods. The plants are described using anatomical and morphological methods. For the anatomical study, plants were treated with bleach (20%) and stained with methylene blue, enhancing observation of the thallus structure. Key results. The plants consist of a stout, erect axis with a subepidermis and regularly spaced, horizontally spreading and flattened, densely 4-6 pinnate fronds, which are arranged in whorls. The axis and primary branches are wingless; the younger branches are broadly winged. An erect axis with a subepidermis and winged branches are also seen in the neotropical R. aberrans, R. ciliolata, R. fucoidea, R. gradsteinii, R. pallida, R. poeppigiana and R. wallisii, but these species are less densely pinnate and the branches are not arranged in horizontally spreading, flattened whorls, and are mostly fully winged. In its verticillate habit, the new species is similar only to members of R. subg. Arconeura, including R. prehensilis from Tierra del Fuego and R. eriocaula from Australasia. A key to dendroid neotropical species of Riccardia is provided. Conclusion. Riccardia verticillata stands out among neotropical Riccardia species by its markedly whorled habit. This discovery adds a further endemic taxon to the Condor region.
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| 23. |
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| 24. |
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| 25. |
- Hooijmaijers, Cortwa
(författare)
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Membrane integrity, oxidative damage and chlorophyll fluorescenceduring dehydration of the thalloid liverwort Monoclea forsteri Hook
- 2008
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Ingår i: Journal of Bryology. - : British Bryological Society. - 0373-6687 .- 1743-2820. ; 30, s. 217-222
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Tidskriftsartikel (refereegranskat)abstract
- Monoclea forsteri Hook. is a thalloid liverwort species that is found in damp habitats and can, therefore, be expected to be sensitive to dehydration. It does, however, have some unique chemical constituents and anatomical features that could play a role in dealing with the adverse effects of water deficits. Corresponding to the habitat, M. forsteri lost its turgor at high relative water content (RWC=0.90) and did not survive drying below 20% RWC. Moreover, the gametophytes showed an increase in malondialdehyde content and a depletion of the ascorbate pool during dehydration, indicating oxidative damage. Cellular constituents did not affect turgor pressure during drying and electrolyte leakage from the cells was greatly increased at RWC< 0.20. Photosynthetic processes seemed not to be affected by the loss of turgor, but a decline appeared to correlate with an increase in electrolyte leakage. A speedy and fully sustained recovery from dehydration was realized from water contents above 30% and seemed only to be possible if membrane integrity could be preserved. Anatomical characteristics within M. forsteri gametophytes deserve further investigation to better understand their physiological functions.
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| 26. |
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| 27. |
- Hylander, Kristoffer, et al.
(författare)
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Liverworts of southwest Ethiopian montane forests : ecological and biogeographical notes
- 2010
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Ingår i: Journal of Bryology. - 0373-6687 .- 1743-2820. ; 32, s. 92-100
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Tidskriftsartikel (refereegranskat)abstract
- Ethiopia has diverse topographic features and climatic conditions with a diverse flora. The liverwort flora of southwest Ethiopia is practically unknown, despite a favourable climate and the occurrence of suitable ecosystems such as montane rainforests. During an ecological study of diversity patterns of bryophytes and vascular plants in relation to land use, we recorded many bryophyte species. In this paper we report the finding of 89 species of liverworts, and give short ecological notes and describe the distribution (locally and in Africa) for each species. Of these, 51 species are newly reported from Ethiopia. It is thus obvious that Ethiopia is considerably richer in liverworts than might be expected from previous checklists.
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| 28. |
- Hylander, Kristoffer, et al.
(författare)
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Mosses of southwest Ethiopian montane forests - notes on their occurrence pattern and many new country records
- 2017
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Ingår i: Journal of Bryology. - : Informa UK Limited. - 0373-6687 .- 1743-2820. ; 39:4, s. 342-352
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Tidskriftsartikel (refereegranskat)abstract
- One hundred and thirty-nine taxa of mosses are reported from the montane forest zone of southwest Ethiopia. Of these, 53 taxa are new country records and Meteoriopsis reclinata (Mull. Hal.) M. Fleisch. ex Broth. is, in addition, new to Africa. Most of the new records are of species also found in Uganda, Kenya or Tanzania, but there are some surprises, such as Fabronia perciliata Mull. Hal. with the closest location in South Africa and Namibia, Entodontella cameruniae Broth. previously known only from West Africa and Bryomaltaea obtusifolia (Hook.) Goffinet, otherwise reported only from the Democratic Republic of the Congo. We list all taxa and give a short account of their frequency and in which habitat and on which substrate they grow. That such a large proportion of the species are new to the country suggests that Ethiopia is bryologically very under-explored, and that further exploration will reveal many additional species. In particular, the remnant forests of southwest Ethiopia are likely to be of great importance as bryophyte hotspots.
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| 29. |
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| 30. |
- Jägerbrand, Annika K., et al.
(författare)
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Responses of bryophytes to simulated environmental change at Latnjajaure, northern Sweden
- 2003
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Ingår i: Journal of Bryology. - : Taylor & Francis. - 0373-6687 .- 1743-2820. ; 25:3, s. 163-168
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Tidskriftsartikel (refereegranskat)abstract
- We simulated a predicted environmental change in a subarctic-alpine plant community to study short-term growth in Hylocomium splendens, and three-year effects in abundance changes of the five most common bryophytes at Latnjajaure, northern Sweden. The experiment had a factorial design with increased temperature and nutrients, alone and in combination. Moss growth was measured during the 1995 growing season, and we measured species abundance before and after three years of environmental perturbation. The combined treatments of fertilizer and temperature enhancement caused a decreased growth in length and dry weight in H. splendens. There was a significant decrease in abundance of Rhytidium rugosum in the combined temperature and fertilizer treatment. The other four common bryophyte species (Aulacomnium turgidum, Dicranum groenlandicum, Hylocomium splendens, and Ptilidium ciliare) showed weaker, but not significant trends in the same direction. As the bryophytes are an important component of arctic and subarctic vegetation, we expect that they will play a key role in the impact of anticipated Global Change on the ecosystems.
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| 31. |
- Jägerbrand, Annika, 1972-, et al.
(författare)
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Variation in responses to temperature treatments ex situ of the moss Pleurozium schreberi (Willd. ex Brid.) Mitt. originating from eight altitude sites in Hokkaido, Japan
- 2014
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Ingår i: Journal of Bryology. - : Taylor & Francis. - 0373-6687 .- 1743-2820. ; 36:3, s. 209-216
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Tidskriftsartikel (refereegranskat)abstract
- Thermal acclimatisations are important for the survival and growth of individuals and populations but seldom studied for different populations of bryophytes. The aims of this study were to (I) investigate if responses to temperature treatments were independent of the site sampled or if the intra- and inter-population variation in responses were larger than the responses to the temperature treatments (control, press, and pulse), and to (II) examine if experimental responses varied, depending on the sampled sites. We collected samples of the circumpolar bryophyte species, Pleurozium schreberi (Willd. ex Brid.) Mitt., originating from eight altitude sites on Mt. Oakan in Hokkaido, Japan, and exposed them to three different temperature treatments ex situ for four weeks. Thermal acclimatisation was estimated by measuring responses in growth length increase, biomass increase, number of branches, and the maximum quantum yield of PS II (Fv/Fm). We found that responses to temperature treatments were dependent on the site sampled, and that differences were most pronounced in the length increase. Results also shows that the responses to experimental treatments may differ between sites. Our results therefore raise important concerns regarding the general validity of both ex situ and in situ experiments when performed on a single or a limited number of sites.
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| 32. |
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| 37. |
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| 38. |
- Mälson, Kalle, et al.
(författare)
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Competitive hierarchy, but no competitive exclusions in experiments with rich fen bryophytes
- 2009
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Ingår i: Journal of Bryology. - 0373-6687 .- 1743-2820. ; 31:Part 1, s. 41-45
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Tidskriftsartikel (refereegranskat)abstract
- Competitive exclusion among species with high niche overlap has been questioned by plant ecologists over the last decades. In this study, we used a greenhouse experiment to test the role of competition for community dynamics and composition among bryophytes in boreal rich (calcareous) fens. We evaluate the rate and direction of competition between three of the most common bryophytes in these wetlands, Campylium stellatum, Scorpidium cossonii and Scorpidium scorpioides. A pair-wise experimental setup with equal amounts of initial plant material of the species was used and the experiment continued for two years. To assess the competitive outcome we measured the area expansion of one species into the part of the experimental containers covered by its competitor, and the height growth of each species. Differences were observed between tested species for total spatial expansion into the area of its competitor. C. stellatum and S. cossonii showed similar total spatial expansion, while S. scorpioides showed very low spatial expansion. The spatial expansion also depended on the identity of the other species in the combination. All three pair-wise interactions were strongly asymmetric, and in qualitative terms a competitive hierarchy could be established. However, this did not lead to competitive exclusions, even though the experimental containers were small and the two years of continuous growth in the greenhouse would correspond to several years of growth under field conditions. The results suggest that in the natural habitat, where interactions are further weakened by microtopographic niche separation and interrupted by fine-scale disturbances, competitive exclusions are probably rare, if they occur at all.
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| 39. |
- Natcheva, Rayna, et al.
(författare)
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Genetic diversity in populations of Sphagnum capillifolium from the mountains of Bulgaria, and their possible refugial role
- 2003
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Ingår i: Journal of Bryology. - : Informa UK Limited. - 1743-2820 .- 0373-6687. ; 25:2, s. 91-99
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Tidskriftsartikel (refereegranskat)abstract
- Genetic diversity in eight populations of Sphagnum capillfolium from different Bulgarian mountains was investigated by means of isozyme electrophoresis. High levels of allelic diversity were found (H-s = 0.119), comparable to earlier estimates for northern European populations (H-s = 0.116). Strong differentiation among populations and a low number of widespread genotypes suggest a high degree of isolation and restricted gene flow between populations, which is consistent with generally small and scattered populations. The large proportion of distinguishable genotypes (mean 0.498) suggests high levels of out-crossing either currently or in the past. Introgression between S. capillfolium and S. rubellum, a species not found in Bulgaria, was suggested by the occurrence of rubellum-alleles in five populations from different mountains. This could be explained by an ancient hybridization event in a sympatric population. Based on (1) the high genetic diversity, (2) the fairly wide distribution of alien alleles, and (3) the isolated distribution of populations even within one mountain. a possible survival of S. capillifolium in the Balkan area during the Quaternary ice periods is hypothesized.
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| 40. |
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| 41. |
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| 42. |
- Patiño, Jairo, et al.
(författare)
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Unveiling the nature of a miniature world : a horizon scan of fundamental questions in bryology
- 2022
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Ingår i: Journal of Bryology. - : Informa UK Limited. - 0373-6687 .- 1743-2820. ; 44:1, s. 1-34
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Tidskriftsartikel (refereegranskat)abstract
- Introduction. Half a century since the creation of the International Association of Bryologists, we carried out a review to identify outstanding challenges and future perspectives in bryology. Specifically, we have identified 50 fundamental questions that are critical in advancing the discipline.Methods. We have adapted a deep-rooted methodology of horizon scanning to identify key research foci. An initial pool of 258 questions was prepared by a multidisciplinary and international working group of 32 bryologists. A series of online surveys completed by a broader community of researchers in bryology, followed by quality-control steps implemented by the working group, were used to create a list of top-priority questions. This final list was restricted to 50 questions with a broad conceptual scope and answerable through realistic research approaches.Key results. The top list of 50 fundamental questions was organised into four general topics: Bryophyte Biodiversity and Biogeography; Bryophyte Ecology, Physiology and Reproductive Biology; Bryophyte Conservation and Management; and Bryophyte Evolution and Systematics. These topics included 9, 19, 14 and 8 questions, respectively.Conclusions. Although many of the research challenges identified are not newly conceived, our horizon-scanning exercise has established a significant foundation for future bryological research. We suggest analytical and conceptual strategies and novel developments for potential use in advancing the research agenda for bryology.
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| 43. |
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| 44. |
- Sundberg, Sebastian, et al.
(författare)
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Spore number in Sphagnum and its dependence on spore and capsule size
- 1998
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Ingår i: Journal of Bryology. - 0373-6687 .- 1743-2820. ; 20:1, s. 1-16
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Tidskriftsartikel (refereegranskat)abstract
- Spore number in eight species of Sphagnum, representing five taxonomic sections, was investigated in relation to capsule and spore size. Mean spore number ranged from 18,500 in S. tenellum to 243,000 in S. squarrosum. There was considerable intraspecific variation in spore number, which was mainly related to capsule size. The interspecific variation in spore number was determined by both capsule and spore size, with higher numbers of spores in species with large capsules and small spores. Capsule size among species seems to be positively correlated to the size of the capitulum. Spore size showed a strong, positive relationship to capsule size in three species studied, that was fitted by a quadratic regression. The smallest capsule analysed for each of the eight species always had the smallest spores, but in only two species did the largest capsule have the largest spores, further indicating a common curvilinear relationship between spore size and capsule size. The strong relationship (R2=O.98) obtained in a linear regression in which the capsule size to spore size ratio was used to predict spore number in different species, makes it possible to estimate the spore output of other species or populations of Sphagnum, from sizes of capsules and spores. The sizes of spores measured in this study agreed with results obtained in at least one previous study, but were generally smaller than those reported in several other studies. The discrepancy probably depends on the method of spore preparation. The present study identifies potential sources of errors in spore counts and measurements. Measures which help to avoid or correct for errors are evaluated to facilitate further studies.
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| 45. |
- Tyler, Torbjörn, et al.
(författare)
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Determinants of bryophyte species composition and diversity on the Great Alvar of oland, Sweden
- 2018
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Ingår i: Journal of Bryology. - : TAYLOR & FRANCIS LTD. - 0373-6687 .- 1743-2820. ; 40:1, s. 12-30
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Tidskriftsartikel (refereegranskat)abstract
- Factors driving the species richness and distribution of bryophytes are poorly studied and not well understood, particularly in grasslands. We analysed the occurrence of bryophyte species and variation in species richness across 674 plots (0.5 m x 0.5 m) in alvar vegetation (grassland on limestone pavement with thin or no soil) on oland (Sweden) in relation to substrate characteristics and chemistry, inundation frequency, grazing pressure and geographical variables. We found 148 taxa, including 11 nationally red-listed ones. Species richness per plot was significantly associated with substrate type, positively associated with pH and grazing intensity, but negatively associated with soil depth. However, richness of species typical of, or restricted to, alvar habitats responded differently to richness of species more common in other habitats. Typical alvar species were favoured by high pH, shallow soil and low phosphate availability, while generalists preferred relatively low pH, higher phosphate availability and organic or mull soil types. Distance from the alvar margin had only weak effects. Concerning the effects on individual species and community composition, inundation frequency and pH were found to have the largest effects, although other factors (substrate type, soil depth, bare soil, bare stone, phosphate availability and grazing pressure) were more important for some individual species, stressing the importance of microsite variability and variability in management for regional species richness. From a conservation perspective, it is concluded that grazing is generally positive whilst factors increasing phosphate availability may disadvantage the typical alvar species, and proximity to the alvar margin is not a major problem.
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| 46. |
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| 47. |
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| 48. |
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| 49. |
- Rosengren, Frida, et al.
(författare)
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Sexual reproduction in the phyllodioicous bryophyte Homalothecium lutescens (Hedw.) H.Rob. in relation to habitat age, growth conditions and genetic variation
- 2014
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Ingår i: Journal of Bryology. - 1743-2820. ; 36:3, s. 200-208
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Tidskriftsartikel (refereegranskat)abstract
- Sporophyte production and female fertility were investigated in seventeen calcareous grassland demes of the moss Homalothecium lutescens (Hedw.) H.Rob. on the Baltic island of Öland, with the aim of understanding the relationships between sexual reproduction, habitat age, genetic variation and factors related to growth conditions. The overall proportion of fertile female shoots (with perichaetia) was 35%. Fertility status at the level of individual shoots was positively associated with shoot length and density, while within deme fertility was positively associated with bush cover. There was no association between female fertility and habitat age, genetic diversity (HS) or allelic richness. Out of 1344 investigated shoots, only two were normal-sized fertile males. Dwarf males were also extremely rare, and found almost exclusively on shoots with sporophytes. Few sporophytes were observed (in the two demes with highest fertility and bush cover). No relationship between genetic variation and the frequency of sporophytes and males was found. The lack of a relationship between sexual reproduction and genetic variation suggests that sexual reproduction may not occur in the same grassland fragments as the recruitment of new clones (from spores or vegetative fragments). The majority of the dry, open grassland habitats, where H. lutescens is typically found in the study area, appear to be suboptimal for both dwarf males and fertilization. Sexual reproduction is more likely to occur in shaded (although grazed) grassland patches, where moisture levels are likely to be higher and the moss colonies are generally more vigorous.
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| 50. |
- Ross, S E, et al.
(författare)
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Variation and control of growth-form in the moss Hylocomium splendens
- 2001
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Ingår i: Journal of Bryology. - 1743-2820. ; 23, s. 283-292
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Tidskriftsartikel (refereegranskat)abstract
- The moss Hylocomium splendens has both sympodial and monopodial forms of growth. One aim of this study was to document the growth-form of shoots from different populations. A further aim was to discover the extent to which genetic or environmental factors determine whether monopodial or sympodial growth-form is predominant in a population. Switching between growth-forms within shoots occurs in most populations. Populations in forest habitats in temperate to mid-Arctic environments have predominantly sympodial shoots whereas shoots of populations from tundra habitats, in high-Arctic environments or at high altitudes, are predominantly monopodial. Transplant experiments showed that sympodial and monopodial shoots can respond plastically, by changing growth-form to some extent in different environments, and that high nutrient availability is an important environmental factor in promoting sympodial growth-form. However, even after 14 years, transplants did not show the same variation in growth-form as shoots in natural populations at the transplant sites. This suggests that populations are also genetically differentiated with respect to growth-form.
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