Do birds disperse mosses? Evidence of endozoochory in upland geese Chloephaga picta and white-bellied seedsnipes Attagis malouinus in sub-Antarctic Chile

Birds are known to act as potential vectors for the exogenous dispersal of bryophyte diaspores. Given the totipotency of vegetative tissue of many bryophytes, birds could also contribute to endozoochorous bryophyte dispersal. Research has shown that fecal samples of the upland goose (Chloephaga picta) and white-bellied seedsnipe (Attagis malouinus) contain bryophyte fragments. Although few fragments from bird feces have been known to regenerate, the evidence for the viability of diaspores following passage through the bird intestinal tract remains ambiguous. We evaluated the role of endozoochory in these same herbivorous and sympatric bird species in sub-Antarctic Chile. We hypothesized that fragments of bryophyte gametophytes retrieved from their feces are viable and capable of regenerating new plant tissue. Eleven feces disc samples containing undetermined moss fragments from C. picta (N=6) and A. malouinus (N=5) and six moss fragment samples from wild collected mosses (Conostomum tetragonum, Syntrichia robusta, and Polytrichum strictum) were grown ex situ in peat soil and in vitro using a agar-Gamborg medium. After 91 days, 20% of fragments from A. malouinus feces, 50% of fragments from C. picta feces, and 67% of propagules from wild mosses produced new growth. The fact that moss diaspores remained viable and can regenerate under experimental conditions following the passage through the intestinal tracts of these robust fliers and altitudinal and latitudinal migrants, suggests that sub-Antarctic birds may play a critical role in bryophyte dispersal. This relationship may have important implications in the way bryophytes disperse and colonize habitats facing climate change. Keywords: birds, bryophyte dispersal, endozoochory, mosses, sub-Antarctic

Isolation and characterization of culturable actinobacteria associated with Polytrichum strictum (Galindez Island, the maritime Antarctic)

The main objective of the study is the evaluation of the diversity of actinobacteria associated with Polytrichum strictum — dominant species of widespread Antarctic Тall moss turf subformation and their characteristics as the producers of biologically active compounds. The actinobacterial isolates were isolated by direct inoculation, phenol pretreatment, and heated treatment. The cultural properties of the isolates were evaluated using diagnostic media. The antimicrobial activity of the isolates was determined by the point inoculations method. The phylogenetic analysis was based on sequence analysis of the 16S rRNA gene. The biosynthetic genes screening was performed using polymerase chain reaction. A total of 23 actinobacterial isolates associated with P. strictum were isolated, the four identified genera being Streptomyces (7 isolates), Micromonospora (14 isolates), Kribbella (1 isolate), and Micrococcus (1 isolate). Eight psychrotrophic strains of all identified genera were identified. The optimal pH values for all isolates were in the range 6–10. Four isolates grew on the medium with 7.5% NaCl. A significant number of the isolates showed a wide range of enzymatic activities. Antagonists of a wide range of pathogenic microorganisms were found, including against multidrug-resistant strain of Candida albicans and Methicillin-resistant Staphylococcus aureus. Some strains were active against phytopathogenic bacteria, namely three strains against Erwinia amylovora, one strain against Agrobacterium tumefaciens, and one strain against Pectobacterium carotovorum. More than half of the isolates showed antifungal activity against Fusarium oxysporum and Aspergillus niger. The biosynthetic genes involved in synthesizing a wide range of bioactive compounds were found in more than 80% of isolates. Antarctic actinobacteria isolated in this study demonstrate potential as the producers of a wide range of biologically active compounds. Further studies of these actinobacteria may lead to the identification of previously unknown biologically active compounds.

Investigating the Potential Use of RADARSAT-2 and UAS imagery for Monitoring the Restoration of Peatlands

The restoration of peatlands is critical to help reduce the effects of climate change and further prevent the loss of habitat for many species of flora and fauna. The objective of this research was to evaluate RADARSAT-2 satellite imagery and high-resolution Unmanned Aerial Systems (UASs) to determine if they could be used as surrogates for monitoring the success of peatland restoration. Areas of peatland that were being actively harvested, had been restored from past years (1994–2003), and natural shrub bog in Lac St. Jean, Quebec were used as a test case. We compared the Freeman–Durden and Touzi decompositions by applying the Bhattacharyya Distance (BD) statistic to see if the spectral signatures of restored peatland could be separated from harvested peat and natural shrub bog. We flew Unmanned Aerial Surveys (UASs) over the study site to identify Sphagnum and Polytrichum strictum, two indicator species of early peatland restoration success. Results showed that the Touzi decomposition was better able to separate the spectral signatures of harvested, restored, and natural shrub bog (BD values closer to 9). Symmetric scattering type αs1, Helicity |τ1,2,3|, a steep incidence angle, and peak growing season appear to be important for separating the spectral signatures. We had moderate success in detecting Sphagnum and Polytrichum strictum visually by using texture and pattern but were unable to use colour due to differences in sun angle and clouds during the UAS flights. Results suggest that RADARSAT-2 data using the Touzi decomposition and UAS imagery show potential for monitoring peatland restoration success over time.

Characterization and Phylogenetic Analysis of Chloroplast and Mitochondria Genomes from the Antarctic Polytrichaceae Species Polytrichum juniperinum and Polytrichum strictum

In this study, the organelle genomes of Polytrichum juniperinum Hedw. and Polytrichum strictum Menzies ex Brid. (Polytrichaceae, Bryophyta) from Antarctica were sequenced and compared with the plastomes of the model moss species Physcomitrella patens Brid. The sizes of the cpDNA in P. juniperinum and P. strictum were estimated to be 55,168 and 20,183 bp, respectively; the sizes of the mtDNA were 88,021 and 58,896 bp, respectively. The genomes are very similar to each other, with the possible loss of petN in the cpDNA, which also showed some gene inversions when compared with the cpDNAs of P. patens Brid. In the mtDNA, it is possible that rps10 was lost. In contrast, Antarctic Polytrichaceae species have nad7 and orf187, without the occurrence of rearrangement events. Phylogenomic analyses of the plastid and mitochondria revealed that the majority-rule tree suggests some differences in the plastids ancestry, however, P. juniperinum and P. strictum were grouped in the same clade in chloroplast, but in mitochondria P. strictum was grouped with Atrichum angustatum (Brid.) Bruch & Schimp. This study helped us understand the evolution of plastomes and chondriosomes in the family Polytrichaceae, and suggest a hybridization event with relation to the mitochondrial data.

Responses of the mosses Sphagnum capillifolium and Polytrichum strictum to nitrogen deposition in a bog: growth, ground cover, and CO2 exchange

Previous studies have shown that atmospheric nitrogen (N) deposition is detrimental to sphagna, which are a group of mosses that are important for carbon cycling in northern peatlands. Little is known about species interactions, such as relative responses of tall moss Polytrichum strictum Menzies ex Brid. and sphagna. We studied the effects of N deposition on growth, abundance, and CO2 exchange of the moss species Sphagnum capillifolium (Ehrh.) Hedw. and Polytrichum strictum in an experiment at a temperate bog. Sphagnum growth and cover decreased significantly with high-dose N treatment (6.4 g N·m−2·year−1) in years 4 and 5 of treatment, whereas the same parameters increased for Polytrichum compared with the control. Net CO2 exchange, gross photosynthesis (Pg), and dark respiration (R) in the intact moss cores, which were measured in year 5 of treatment, were elevated in the cores that had been treated with the high-dose of N, compared with the control, and this was associated with increased abundance of Polytrichum. The moss cores where Polytrichum was removed, however, had increased mass-based R with the high-dose N treatment. Our results showed that S. capillifolium at Mer Bleue may be close to N saturation, as 5 years of high-dose N loading (6.4 g N·m−2·year−1 + background) was harmful to this species, possibly as a result of increased respiratory cost. Polytrichum strictum had a competitive advantage, at least in the short-term, through allocating excess N to growth. This change in moss layer composition deserves further attention, as a shift to more easily decomposable litter, without corresponding increases in plant production, could reduce the carbon sequestration of the bog.

Communities of the class Oxycocco-Sphagnetea Br.-Bl. et R. Tx. 1943 in the East European tundras

According to the tradition of the Braun-Blanquet school 3 new associations belonging to Oxycocco-Sphagnetea Br.-Bl. et R. Tx. 1943 class and Sphagnetalia magellanici (Pawl. 1928) Kдstn. et Flцss. 1933 order were described on the latitudinal gradient of the East European tundras. New ass. Carici globularis–Pleurozietum schreberi occurs on peaty gley soils of watersheds in the south part of tundra zone and in the northern forest-tundra. It is related to the Oxycocco–Empetrion hermaphroditi Nordh. 1936 alliance included the dwarf-shrub-Sphagnum communities of ridges and hummocks of the ombrotrophic raised bogs and aapa mires in subcontinental and continental areas of the taiga zone of the North Eurasia (Lapshina, 2010; Ermakov, 2012). Palsa peatlands are widespread in permafrost zone in the East European tundras. Shape and size of palsa mounds vary fr om the north to the southern direction. Polygon and small palsa peatlands are distributed in typical tundras (on the Barents Sea islands and coastal areas) in the continuous permafrost zone. The lowest flat palsa peatlands can be seen in the southern tundra in discontinuous permafrost zone. The high palsa peatlands and slightly differentiated peat plateau can be found in the northern forest tundra in the insular permafrost zone. All palsa peatlands have similar ecological features: oligotrophic, hyperacidity, closeness of permafrost, good drainage conditions and the dry upper layer of peat. The lichens (Cladonia and Flavocetraria genera) predominate in the ground layer of palsa peatlands. A role of Sphagnum moss is not remarkable, other mosses such as Dicranum elongatum and Polytrichum strictum dominate there. The new Rubo chamaemori–Dicranion elongati alliance are proposed to classify the dwarf-shrub-cloudberry-moss-lichen communities of oligotrophic palsa and polygon peatlands of the Subarctic region. Creation of the new alliance has some challenges: 1) the same vascular plants (Empetrum hermaphroditum, Ledum decumbens, Rubus chamaemorus, Vaccinium vitis-idaea, V. uliginosum) dominate on ombrotrophic raised bogs and aapa mires, but they are typical for palsa and polygon peatlands also; these species are listed already as character ones for existing higher syntaxonomic units, including Oxycocco–Empetrion hermaphroditi alliance; 2) in the East European tundras, on palsa and polygon peatlands the dominating lichens (Oxycocco-Sphagnetea class) have the same high constancy and they are often abundant in Loiseleurio-Vaccinietea Eggler ex Schubert 1960 class communities, commonly grown in the sandy habitats, therefore they are not characteristic species for both classes. There are 18 species of lichens (Lavrinenko, Lavrinenko, 2013), including Cladonia arbuscula, C. rangiferina, Cetraria islandica, Flavocetraria nivalis, defining physiognomic similarity of plant communities on peaty and sandy soils. To solve the problem, we propose to distinguish a new Rubo chamaemori–Dicranion elongati alliance based on a combination of differentiating taxa (see Molenaar, 1976; Matveyeva, 2006) such as: Andromeda polifolia subsp. pumila, Betula nana, Cetraria islandica, Cladonia arbuscula, C. rangiferina, Dic­ra­num elongatum, Empetrum hermaphroditum, Fla­vocetraria nivalis, Ledum decumbens, Polytrichum strictum, Rubus chamaemorus, Vaccinium vitis-idaea, V. uliginosum. Among them following species Andromeda polifolia subsp. pumila, Dicranum elongatum, Ledum decumbens, Polytrichum strictum, Rubus chamaemorus are character selective regional species of the alliance. The syntaxonomic analysis was based on 185 relevйs made from 1997 to 2012 in 35 regions in the Timanskaya, Malozemelskaya and Bolshezemelskaya tundras as well as on Kolguev, Dolgyi and Vaigach Islands. Two associations (one of them is represented by 3 subassociations) were identified and described on the palsa peatlands. The plant communities of 3 syntaxa are spread in the typical tundra subzone: ass. Tephroserido atropurpureae–Polytrichetum stricti — in the northern strip of subzone, on polygonal peatlands on the Vaigach Isl., ass. Rubo chamaemori–Dicranetum elongati subass. inops — in the southern strip of subzone, on polygonal and low palsa peatlands on the Kolguev and Dolgyi Isl., ass. R. c.–D. e. subass. caricetosum rariflorae — ibid, on small palsa and polygon peatlands on the low marine terraces along the Barents Sea coast. The plant communities of ass. R. c.–D. e. subass. typicum are common in the south tundra subzone and the northern forest-tundra on the low and high palsa peatlands and slightly differentiated peat plateau in the Timanskaya, Malozemelskaya and Bolshezemelskaya tundras. Plant communities of these syntaxa are very sensitive to anthropogenic load and they react by changing the species abundance and their frequency. Three subassociations of Rubo chamaemori–Dicranetum elongati association got two variants: typica — distinguished on undisturbed peatlands; Ochrolechia frigida — typical for sites damaged by reindeers grazing. Plant communities referred to variant typica have a high abundance of fruticose lichens (Cladonia arbuscula, C. rangiferina); another variant Ochrolechia frigida has a bigger number of species; wh ere the high constancy and abundance got the crustose lichens (Ochrolechia androgyna, O. frigida, O. inaequatula, Icmadophila ericetorum) and cup-shaped Cladonia species (Cladonia coccifera, C. cornuta, C. deformis, C. pleurota, C. sulphurina), growing on dead plant material and peats. Such species as Dicranum elongatum, Rubus chamaemorus and some dwarf shrubs are noticeable by their abundance. Since the palsa peatlands are wide spread over the territory of plain tundras not only in eastern European part of Russia but also in the Western Siberia, we can predict that the new associations belonging to the alliance Rubo chamaemori–Dicranion elongati will be described.

Cellulose-decomposing fungi in Peatlands occupied by invasive moss Campylopus introflexus

Repečkienė J., Jukonienė I., Salina O., 2012: Cellulose-decomposing fungi in peatlands occupied by invasive moss Campylopus introflexus [Celiuliozę skaidantys grybai durpynuose, kuriuose plinta invazinė samana Campylopusintroflexus]. - Bot. Lith., 18(1): 46-57. Studies on the abundance and genera composition of cellulose-decomposing fungi in four differently disturbed peatlands occupied by invasive moss Campylopus introflexus were carried out in autumn, spring and summer seasons. The abundance of fungi under C. introflexus was compared with the abundance of fungal communities under other plants occupying the same habitats (Polytrichum strictum, Eriophorum angustifolium, Callunavulgaris) and bare peat. The serial dilution plate technique was applied for isolation and enumeration of cellulose- decomposing fungi. The large amount of organic matter as well as acidic reaction of peat creates favourable conditions for the development of fungi at the studied sites. The number of cellulose-decomposing fungi depended on the peatland type, prevailing plants and season. The richness of fungal genera (15) was determined under Campylopus introflexus. Fungal isolates belonging to the Penicillium, Trichoderma, Fusarium genera and the Zygomycetes class prevailed.

Natural revegetation of two block-cut mined peatlands in eastern Canada

Limited areas of post-mined peatlands are recolonized by Sphagnum-dominated communities. This study aims to recognize the spontaneous Sphagnum re-establishment process and to verify if Sphagnum directly colonizes the residual peat. Conditions favoring Sphagnum revegetation are suggested. Analyses of vegetation macrofossils of the newly formed peat allow the identification of colonizing species and vegetation succession profile. Botanical components of the pioneer horizon suggest that Sphagnum species can directly colonize the residual peat. When Polytrichum strictum (Kaulf.) Presl and Eriophorum spissum Fernald are present as early colonists, they are rapidly overgrown by Sphagnum species in the succession profile. Vegetation succession resulted mainly in the formation of hummocks and lawns dominated by Sphagnum fuscum (Schimp.) Klinggr., Sphagnum capillifolium (Ehrh.) Hedw., and Sphagnum magellanicum Brid., with a more or less dense ericaceous shrub cover. Floristic, hydrological, and chemical features indicate that a fibric peat accumulation ecosystem is progressively or partially restored.Key words: cut-over peatlands, restoration, Sphagnum, vegetation macrofossil, acrotelm.