Does the width of isolated ravine forests influence moss and liverwort diversity and composition?—A study of temperate forests in South Africa

The evidence of microclimatic edge effects through forest/open area ecotones is firm. How this affects the species composition near edges is less well understood and documented. In south-western South Africa shrub-dominated regularly burnt vegetation (i.e. fynbos) is the most common vegetation with indigenous temperate forests naturally occurring mostly in ravines on mountain slopes. The size and width of these forest patches varies considerably. In order to understand how the width of forest patches affects species composition of mosses and liverworts we investigated 20 forest patches of different width. In each forest patch we compiled a total species list, and collected data on selected environmental variables, for a plot of 10×20 m. No significant relationship was found between patch width and the number of either moss or liverwort species. However, the species composition of mosses (but not liverworts) changed along the gradient of patch width. The variation in number of species was large (8–29 mosses and 11–33 liverworts) among the plots and we propose that factors other than distance to the forest edge may be more important in structuring the bryophyte community of these ravine forests. One such factor that is likely to be important is the climatic difference among the plots. There is variation in features, such as precipitation, summer temperature, cloudiness, and the amount of fog, for which we do not have data but that could overrule the microclimatic differences due to edge effects.     

Effects of Retention Felling on Epixylic Species in Boreal Spruce Forests in Southern Finland

We studied the effects of patch retention felling and soil scarification by harrowing on the coverage and species richness of epixylic species in boreal Norway spruce (Picea abies) forests in Southern Finland. The epixylics were investigated from both the retention tree groups (RTGs) and the surrounding felling areas before and after fellings and after scarification on consecutive years. The cover percentage of all included species groups was shown to decrease after the felling, especially in the felling areas (vascular plants, ?0.4%; mosses, ?27.8%; liverworts, ?4.0%; and lichens,?2.1%). The decrease was considerable also in the RTGs. The amount of dead moss increased in both the areas indicating microclimatic changes. Species richness also declined rapidly after the first year, especially in the felling areas (vascular plants, ?2.2%; mosses, ?27.3%; liverworts, ?30.3%; and lichens, ?22.9%). Scarification also decreases covers and species richness of bryophytes. After the second year, the covers of the species groups generally started to regain, especially in the untreated RTGs. The size of RTG was in positive correlation with the total species number. Another main result indicates that it is possible to maintain much higher initial vegetation abundance and diversity in the RTGs than in the felling areas. Coarse woody debris formed by the frequent tree uprootings may also enhance the long‐term survival of epixylics over forest regeneration period. RTGs should be at least 10 times larger than the size used in current Finnish forestry, so that they could function as species refugia.     

Nestedness,SLOSS and conservation networks of boreal herb‐rich forests

Question: Herb‐rich patches are biodiversity hotspots for vascular plants in boreal forests. We ask: Do species occurrences on herb‐rich patches show a non‐random, nested structure?; Does patch size relate to richness of edaphically demanding and red‐listed species?; Does a set of small patches support more edaphically demanding and red‐listed species than a few large patches of the equal area? Location: Eastern Finland (63°04′N, 29°52′E), boreal vegetation zone. Data: Vegetation mapping of 90 herb‐rich sites, varying from 0.05 to 6.93 ha in size and belonging to six different, predetermined forest site types. Results: Using the RANDNEST procedure, only one site type showed a significantly nested pattern, and patch area was not related to “nestedness” in any of the site types. The number of edaphically demanding and red‐listed plant species was positively correlated with a patch size in three forest site types. In all site types, a set of small patches had more edaphically demanding and red‐listed species than did a few large patches of the equal total area. Conclusions: For conservation, it is essential to protect representative sets of different herb‐rich forest site types because flora varies between the site types. Within herb‐rich forest site types, several small areas may support representative species composition. However, successful conservation requires thorough species inventories, because of the high level of heterogeneity between the herb‐rich patches.     

New chloroplast primers for intraspecific variation in Dicranum scoparium Hedw. (Dicranaceae) and amplification success in other bryophyte species

Primers for four loci that amplify cpDNA regions have been designed for population genetic analyses in Dicranum scoparium Hedw. and compared with trnL(UAA)5'exon-trnF. All loci showed intraspecific variation with a number of haplotypes ranging between two and six. trnH-psbA(Dic) showed an intercontinental disjunction, but no variability within the four Swiss populations surveyed, whereas the three remaining loci displayed intrapopulation variability in at least one population (rps19-rpl2, rpoB, trnT-rps4). These primers were additionally tested on 22 bryophytes and three fern species. The primers amplified mostly in mosses and liverworts, but less well in ferns, pointing to their evolutionary distance from the bryophytes.     

Recent advances in phytochemistry of bryophytes-acetogenins, terpenoids and bis(bibenzyl)s from selected Japanese, Taiwanese, New Zealand, Argentinean and European liverworts

Bryophytes contain a large number of terpenoids and phenolic compounds. Recent topics relating to the chemical constituents found in 36 Japanese, 3 New Zealand, 2 European, 1 Argentinean and 1 Taiwanese liverworts and 2 Japanese mosses and their biological activity are discussed. The chemosystematics of some liverworts as well as the chemical relationship between liverworts and mosses, and bryophytes and ferns are also discussed.     

New national and regional bryophyte records, 37

Abstract

We analyzed the form of the UV-absorption spectra and calculated the bulk UV-absorption capacity of the methanolic extracts (BUVACME) in 15 bryophytes (five liverworts and 10 mosses) from unshaded aquatic habitats of Tierra del Fuego (Argentina). BUVACME was obtained as the area under the absorbance curve (AUC) in several ranges of the UV band to allow comparison with the literature data. Both the spectra form and the AUC values depended on the species considered. The spectra showed either no, one or two defined peaks. The peaks were probably due to phenolic derivatives, which could act as both screening compounds and antioxidants. The different AUCs calculated were highly and significantly correlated, and thus it may be unimportant which of these is used. The AUC values of most liverworts were higher than those of most mosses and in particular, the liverworts Noteroclada confluens and Triandrophyllum subtrifidum showed much higher BUVACMEs than those analyzed in any other bryophyte. Thus, the accumulation of UV-absorbing compounds might often increase protection against UV radiation in liverworts, but rarely in mosses. This is in line with the evolutionary differences between these two groups of bryophytes. Except for the two abovementioned liverwort species, BUVACME of aquatic bryophytes from Tierra del Fuego is not particularly different to that found in bryophytes from other zones of the planet.     

广东黑石顶森林苔藓群落特征初探

通过对5个面积为2500m2的样地中树附生和地面苔藓植物的定量调查,初步研究了广东黑石顶森林中苔藓植物多样性特征。本次调查共发现苔藓植物50种,包括30种苔类和20种藓类。样地中树附生苔藓植物40种,地面苔藓植物24种,前者远高于后者。各样地中地面苔藓植物的种类为8-13种,盖度0.59%-1.12%,坡度及小生境的多样性对地面苔藓植物物种多样性及盖度均有很大影响;树附生苔藓植物12-20种,盖度0.63%-1.63%。结果显示30a的次生林中苔藓植物的物种丰富度及盖度均可恢复到与成熟阔叶林接近的水平。相似性分析表明,成熟阔叶林内苔藓植物种类组成与针阔叶混交林及30a的次生阔叶林差异不明显,但前者的苔藓植物群落结构与后者的差异较大。     

Bryophyte community composition and habitat specificity in the natural forests of Terceira,Azores

In order to characterize the main areas of natural forest on Terceira Island (Azores), some of the most interesting European forests due to their rich and diverse flora of endemic as well as relict species, six forest stands were studied and their flora inventoried using 226 randomized quadrats, which revealed one anthocerote, 64 liverworts, 41 mosses and 16 macrolichen taxa. The alpha-diversity of the samples is particularly species-rich, some quadrats (30 × 30 cm) including more than 25 bryophyte species. A quantitative analysis of the vegetationenvironment relationships consistently showed that the distributions of the native forest bryophytes and lichens of Terceira are governed by a complex set of factors related to water availability, the status of the substrata and the influences of the vascular plant community. Considering the generally high values of the Sørensen indices and the low number of specialist species found with Lloyd’s index, the differences are more in terms of dominance of species than in terms of species composition. In fact, substratum type was clearly important in the DCA and TWINSPAN analysis using species cover abundance values, largely explaining the distribution of bryophyte species between Juniperus brevifolia (Seub.) Antoine and Laurus azorica (Seub.) Franco bark. The eight putative plant community type groupings achieved with these multivariate methods were able to elucidate some major bryophyte – substratum relationships, that had not previously been considered and they offer a framework for future research.     

Phylogeny and diversification of bryophytes

The bryophytes comprise three phyla of embryophytes that are well established to occupy the first nodes among extant lineages in the land-plant tree of life. The three bryophyte groups (hornworts, liverworts, mosses) may not form a monophyletic clade, but they share life history features including dominant free-living gametophytes and matrotrophic monosporangiate sporophytes. Because of their unique vegetative and reproductive innovations and their critical position in embryophyte phylogeny, studies of bryophytes are crucial to understanding the evolution of land plant morphology and genomes. This review focuses on phylogenetic relationships within each of the three divisions of bryophytes and relates morphological diversity to new insights about those relationships. Most previous work has been on the mosses, but progress on understanding the phylogeny of hornworts and liverworts is advancing at a rapid pace. Multilocus multigenome studies have been successful at resolving deep relationships within the mosses and liverworts, whereas single-gene analyses have advanced understanding of hornwort evolution.     

浙江西天目山主要森林类型的苔藓多样性比较

苔藓是森林的重要组分, 是森林保护区的重要保护对象, 在物种资源和生态系统功能维护中有重要作用。该研究以浙江西天目山国家自然保护区内7种主要森林类型(落叶矮林、落叶阔叶林、常绿-落叶阔叶混交林、常绿阔叶林、针阔混交林、针叶林和竹林)内的苔藓植物为对象, 调查了32个10 m × 10 m的样地, 记录地面生苔藓植物盖度和树附生苔藓植物多度, 采用重要值、相似性系数、多样性指数分析了森林类型间的苔藓植物多样性差异。共采集969份标本, 隶属41科84属142种, 其中苔类植物13科18属33种, 藓类植物28科66属109种, 优势科为灰藓科、青藓科和羽藓科。2种混交林(常绿-落叶阔叶混交林和针阔混交林)的物种丰富度和多样性指数均高于其余5种森林, 其中物种丰富度以针阔混交林最高, 苔藓植物多样性则以常绿-落叶阔叶混交林最高, 竹林两者均为最低。海拔等环境因子较为接近的植被类型的苔藓植物多样性相似性较高, 常绿阔叶林与针叶林相似性最高, 而落叶矮林和竹林相似性最小。     

Mosses share mitochondrial group II introns with flowering plants, not with liverworts

Extant bryophytes are regarded as the closest living relatives of the first land plants, but relationships among the bryophyte classes (mosses, liverworts and hornworts) and between them and other embryophytes have remained unclear. We have recently found that plant mitochondrial genes with positionally stable introns are well suited for addressing questions of plant phylogeny at a deep level. To explore further data sets we have chosen to investigate the mitochondrial genes nad4 and nad7, which are particularly rich in intron sequences. Surprisingly, we find that in these genes mosses share three group II introns with flowering plants, but none with the liverwort Marchantia polymorpha or other liverworts investigated here. In mitochondria of Marchantia, nad7 is a pseudogene containing stop codons, but nad7 appears as a functional mitochondrial gene in mosses, including the isolated genus Takakia. We observe the necessity for strikingly frequent C-to-U RNA editing to reconstitute conserved codons in Takakia when compared to other mosses. The findings underline the great evolutionary distances among the bryophytes as the presumptive oldest division of land plants. A scenario involving differential intron gains from fungal sources in what are perhaps the two earliest diverging land plant lineages, liverworts and other embryophytes, is discussed. With their positionally stable introns, nad4 and nad7 represent novel marker genes that may permit a detailed phylogenetic resolution of early clades of land plants.     

Diaspore bank of bryophytes in tropical rain forests: the importance of breeding system,phylum and microhabitat

Diaspore banks are crucial for the maintenance and resilience of plant communities, but diaspore banks of bryophytes remain poorly known, especially from tropical ecosystems. This is the first study to focus on the role of diaspore banks of bryophytes in tropical rain forests. Our aim was to test whether microhabitat (substrate type) and species traits (breeding system, phylum) are important in explaining the diaspore bank composition. Using samples cultivated in the laboratory, we assessed the number of species and shoots emerging from bark, decaying wood and soil from two sites of the Atlantic rain forest (montane and sea level) in Brazil by comparing the contribution of species by phylum (mosses, liverworts) and breeding system (monoicous, dioicous). More species emerged from bark (68) and decaying wood (55) than from soil (22). Similar numbers of species were found at both sites. Mosses were more numerous in terms of number of species and shoots, and monoicous species dominated over dioicous species. Substrate pH had only weak effects on shoot emergence. Species commonly producing sporophytes and gemmae had a high contribution to the diaspore banks. These superficial diaspore banks represented the extant vegetation rather well, but held more monoicous species (probably short-lived species) compared to dioicous ones. We propose that diaspore bank dynamics are driven by species traits and microhabitat characteristics, and that short-term diaspore banks of bryophytes in tropical rain forests contribute to fast (re)establishment of species after disturbances and during succession, particularly dioicous mosses investing in asexual reproduction and monoicous mosses investing in sexual reproduction.     

Comparison of in vitro decomposition of bryophytic and tracheophytic plant material

The fossil record of bryophytes is generally poor and infertile plants attributable to liverworts and mosses could also be thalloid vascular plant gametophytes or herbaceous lycophytes respectively. The paucity of the bryophytic record could be the result of relatively rapid degradation of bryophytic material in comparison to that of vascular plants, the absence of lignified cells in bryophytes sustaining this belief. However, certain organs of bryophytes are as robust as those of vascular plants (e.g. spores) and the hydroxybenzofuran polymers produced by some mosses could be of similar preservational resistance to lignins. A simplistic experiment to test the relative resistance to decay of bryophytic material has been undertaken. Its findings suggest that bryophytic plant material has a similar preservational potential to that of a selected vascular plant, particularly in organic rich sediments. This result may be construed to imply that bryophytes were indeed less abundant in the preservational environments of the Coal Measures than might be expected on the basis of current palaeoenvironmental reconstructions.     

Responses of bryophytes to wood-ash recycling are related to their phylogeny and pH ecology

Ash generated by the combustion of solid biofuels is increasingly being returned to the fuel's place of origin (mostly forests). In this way, nutrient depletion and acidification caused by biofuel harvest is counteracted and a waste problem is solved. Concerns about the potential negative effects of ash spreading on forest biodiversity (in particular mosses) have been raised, but little is known. I studied the effects of the application of two types of ash (the most used self-hardened crushed ash including fine particles and a less reactive type, pellets without fine particles) on 28 moss species and 17 liverwort species. In two field experiments, one on transplants of ground-living species and one on wood-inhabiting species in situ, I measured the response during the first two months after ash application. Visible damage (discoloration from green to brown) was assessed for all species and the growth response was measured for 24 ground-living species. The responses to crushed ash were clearly related to the species’ pH ecology and phylogenetic position. The growth of bryophytes associated with acidic conditions (pooled data from 10 species) or considered as being indifferent to pH (4 species) was negatively affected, whereas there was no effect on the growth of bryophytes of non-acidic habitats (10 species). The connection to phylogeny was even clearer. Most taxa responded negatively, but transplants from the moss order Bryales (4 species) and the family Brachytheciaceae (2 species; order Hypnales) grew better when treated with ash. The genera with the clearest negative responses were Sphagnum mosses (5 species), Tetraphis mosses (1 species), Dicranum mosses (6 species), and Barbilophozia liverworts (2 species). The four red-listed wood-inhabiting liverworts studied were not significantly damaged. Concerning ash type, pellets caused smaller effects than crushed ash, both on the positive and negative side. The results show that responses to ash recycling of the bryophyte species included in this study are predictable from their phylogenetic position and/or pH ecology. Further studies are needed to determine the generality of these results and to sort out if phylogeny or current relationship to pH is the primary determinant of the response.     

浙江省清凉峰自然保护区苔藓植物区系成分研究

通过对2013~2014年于清凉峰自然保护区采集的1 500余份苔藓植物标本进行鉴定和文献研究,统计分析了清凉峰自然保护区苔藓植物种类组成,区系地理成分及特点,并对该地区与相邻8个地区藓类植物的丰富度系数比较和相似性系数比较,以明确该地区苔藓植物不同的生态分布类型,揭示浙江清凉峰保护区苔藓植物多样性的变化规律。结果表明:(1)浙江省清凉峰国家自然保护区苔藓植物共有62科143属337种(包括3个变种),其中苔类植物20科29属49种,藓类植物42科114属288种。(2)藓类植物的优势科9个、优势属16个。(3)该地区苔藓植物区系成分主要以东亚成分为主(占总种数41.84%),温带成分次之(占总种数28.57%),热带成分再次之(占总种数20.74%)。(4)浙江清凉峰自然保护区苔藓植物区系与浙江省境内的金华山、大盘山、天目山和凤阳山的亲缘关系较为密切。(5)浙江清凉峰自然保护区苔藓植物生态分布类型复杂多样,以石生类型(占总标本数的47.09%)最多,其次为岩面土生(占总标本数的27.68%)和土生(占总标本数的12.85%)类型。     

东北长白山垂直林带下现代表土花粉与植被关系

在长白山北坡5个垂直植被带的林下采集29个表土(苔藓)样品进行孢粉分析，同时将其结果作对应分析。结果表明，除个别样品，在长白山垂直植被带的孢粉组合中乔木花粉占优势，其中以松属和桦木属最多，在各植被带均有分布。松属花粉最高含量出现在以红松为主的针阔混交林带的孢粉组合中；桦木属花粉则大量见于亚高山岳桦林带和以栎桦为主的阔叶落叶林带，但前者伴有耐寒、旱的小灌从杜鹃花属花粉，而在后者中则见有大量蕨类孢子。阔叶落叶林带的孢粉组合是以类型多、百分含量高的落叶乔木花粉和大量蕨类饱子为特征。亚高山针叶林带的孢粉组合中出现数量众多的云杉属花粉。在高山苔原带孢粉组合中虽然乔木花粉略占优势，但极少或不见蕨类孢子，与其他植被带比较，草本植物和小灌丛花粉明鲜较多，其中杜鹃属花粉含量在草本中占优势，其中出现苔原带的指示花粉——仙女木属。     

Phytohormone Profiling across the Bryophytes

BackgroundBryophytes represent a very diverse group of non-vascular plants such as mosses, liverworts and hornworts and the oldest extant lineage of land plants. Determination of endogenous phytohormone profiles in bryophytes can provide substantial information about early land plant evolution. In this study, we screened thirty bryophyte species including six liverworts and twenty-four mosses for their phytohormone profiles in order to relate the hormonome with phylogeny in the plant kingdom.MethodologySamples belonging to nine orders (Pelliales, Jungermanniales, Porellales, Sphagnales, Tetraphidales, Polytrichales, Dicranales, Bryales, Hypnales) were collected in Central and Northern Bohemia. The phytohormone content was analysed with a high performance liquid chromatography electrospray tandem-mass spectrometry (HPLC-ESI-MS/MS).ConclusionThe apparent differences in conjugation and/or degradation strategies of growth hormones between liverworts and mosses might potentially show a hidden link between vascular plants and liverworts. On the other hand, the complement of stress hormones in bryophytes probably correlate rather with prevailing environmental conditions and plant survival strategy than with plant evolution.     

Mosses,Liverworts, and Hornworts Screened for Antitumor Agents

The National Cancer Institute’s record of bryophytes (mosses, liverworts, and hornworts) screened for biologically active chemicals is reviewed. In 1977, an extract of a moss from Maryland, Polytrichum ohioense, showed cytotoxicity in KB cell culture, but antitumor activity was not discovered in bryophytes until 1980. This led to a greater emphasis in collecting and screening bryophytes during 1980–1981. Samples weighing 0.5–2 kg (dried) were collected for each of 208 species and varieties. These included 184 species in 97 genera of mosses, 23 species in 16 genera of liverworts, and 1 hornwort. The methodologies for field work, extraction, and screening are briefly described. The screening results are summarized in a table listing all species alphabetically by family and by genus. For each species, the origin of the sample (country or state), collector’s number, extract number, type of extract, and 3 bioassays employed (including the dose levels used and toxic dose for the P388 lymphocytic leukemia assay) are indicated. Extracts of 75 species were toxic; extracts of 43 species were active. Activity was especially noted in the moss families Thuidiaceae, Mniaceae, Neckeraceae, Hypnaceae, Brachytheciaceae, Polytrichaceae, Dicranaceae, and Grimmiaceae. The authors suggest that bryophytes are a promising source for discovery of novel biologically active compounds. The possibility that biological activity in bryophytes may be the result of allelopathy, or the reputed ability of bryophytes to accumulate toxic substances, is considered.     

Divergent intron conservation in the mitochondrial nad2 gene: signatures for the three bryophyte classes (mosses,liverworts, and hornworts) and the lycophytes

The slow-evolving mitochondrial DNAs of plants have potentially conserved information on the phylogenetic branching of the earliest land plants. We present the nad2 gene structures in hornworts and liverworts and in the presumptive earliest-branching vascular land plant clade, the Lycopodiopsida. Taken together with the recently obtained nad2 data for mosses, each class of bryophytes presents another pattern of angiosperm-type introns conserved in nad2: intron nad2i1 in mosses; intron nad2i3 in liverworts; and both introns, nad2i3 and nad2i4, in hornworts. The lycopods Isoetes and Lycopodium show diverging intron conservation and feature a unique novel intron, termed nad2i3b. Hence, mitochondrial introns in general are positionally stable in the bryophytes and provide significant intraclade phylogenetic information, but the nad2 introns, in particular, cannot resolve the interclade relationships of the bryophyte classes and to the tracheophytes. The necessity for RNA editing to reconstitute conserved codon entities in nad2 is obvious for all clades except the marchantiid liverworts. Finally, we find that particularly small group II introns appear as a general feature of the Isoetes chondriome. Plant mitochondrial peculiarities such as RNA editing frequency, U-to-C type of RNA editing, and small group II introns appear to be genus-specific rather than gene-specific features.     

东北长白山垂直林带下现代表土花粉与植被关系

在长白山北坡5个垂直植被带的林下采集29个表土(苔藓)样品进行孢粉分析,同时将其结果作对应分析.结果表明,除个别样品,在长白山垂直植被带的孢粉组合中乔木花粉占优势,其中以松属和桦木属最多,在各植被带均有分布.松属花粉最高含量出现在以红松为主的针阔混交林带的孢粉组合中;桦木属花粉则大量见于亚高山岳桦林带和以栎桦为主的阔叶落叶林带,但前者伴有耐寒、早的小灌丛杜鹃花属花粉,而在后者中则见有大量蕨类孢子.阔叶落叶林带的孢粉组合是以类型多、百分含量高的落叶乔木花粉和大量蕨类孢子为特征.亚高山针叶林带的孢粉组合中出现数量众多的云杉属花粉.在高山苔原带孢粉组合中虽然乔木花粉略占优势,但极少或不见蕨类孢子,与其他植被带比较,草本植物和小灌丛花粉明鲜较多,其中杜鹃属花粉含量在草本中占优势,其中出现苔原带的指示花粉--仙女木属.