Dead Moss Research Articles

Moss mortality significantly altered topsoil multifunctionality and microbial networks in a temperate desert

AbstractThe continuous rise in global warming and dramatic changes in precipitation patterns have resulted in frequent extreme weather events, biodiversity loss, and ecosystem degradation. This has resulted in varying degrees of mortality in desert mosses, a ground cover type that maintains desert stability and provides important ecological functions. There is, however, a lack of research on the effects of moss mortality on soil multifunctionality (SMF) and microbial interactions in temperate deserts. This study compared and analyzed the soil nutrient content, enzyme activities, and the associated microbial community structure between living and dead moss crusts in the temperate Gurbantunggut Desert. The results indicated that moss mortality improved SMF by increasing the soil carbon content, nitrogen, phosphorus, and enzymatic activity. However, the mortality also considerably reduced the total biomass and abundance of bacteria and fungi in the topsoil, having no significant effect on their diversity. Additionally, a significant decrease in the connectivity and complexity of the soil bacterial and fungal networks was observed when compared to living moss crusts. This was especially noted in the fungal networks, where fungi were more sensitive than bacteria to moss mortality. Although the natural mortality of mosses increases SMF, there is also an increased risk of nutrient loss, thereby threatening ecosystem sustainability. It is, therefore, imperative to consider the causes of crustal degradation while developing management and restoration processes for degraded desert ecosystems.

Moss kill dates and modeled summer temperature track episodic snowline lowering and ice cap expansion in Arctic Canada through the Common Era

Abstract. Most extant ice caps mantling low-relief Arctic Canada landscapes remained cold based throughout the late Holocene, preserving in situ bryophytes killed as ice expanded across vegetated landscapes. After reaching peak late Holocene dimensions ∼1900 CE, ice caps receded as Arctic summers warmed, exposing entombed vegetation. The calibrated radiocarbon ages of entombed moss collected near ice cap margins (kill dates) define when ice advanced across the site, killing the moss, and remained over the site until the year of their collection. In an earlier study, we reported 94 last millennium radiocarbon dates on in situ dead moss collected at ice cap margins across Baffin Island, Arctic Canada. Tight clustering of those ages indicated an abrupt onset of the Little Ice Age at ∼1240 CE and further expansion at ∼1480 CE coincident with episodes of major explosive volcanism. Here we test the confidence in kill dates as reliable predictors of expanding ice caps by resampling two previously densely sampled ice complexes ∼15 years later after ∼250 m of ice recession. The probability density functions (PDFs) of the more recent series of ages match PDFs of the earlier series but with a larger fraction of early Common Era ages. Post 2005 CE ice recession has exposed relict ice caps that grew during earlier Common Era advances and were preserved beneath later ice cap growth. We compare the 106 kill dates from the two ice complexes with 80 kill dates from 62 other ice caps within 250 km of the two densely sampled ice complexes. The PDFs of kill dates from the 62 other ice caps cluster in the same time windows as those from the two ice complexes alone, with the PDF of all 186 kill dates documenting episodes of widespread ice expansion restricted almost exclusively to 250–450 CE, 850–1000 CE, and a dense early Little Ice Age cluster with peaks at ∼1240 and ∼1480 CE. Ice continued to expand after 1480 CE, reaching maximum dimensions at ∼1880 CE that are still visible as zones of sparse vegetation cover in remotely sensed imagery. Intervals of widespread ice cap expansion coincide with persistent decreases in mean summer surface air temperature for the region in a Community Earth System Model (CESM) fully coupled Common Era simulation, suggesting the primary forcings of the observed snowline lowering were both modest declines in summer insolation and cooling resulting from explosive volcanism, most likely intensified by positive feedbacks from increased snow cover and sea ice and reduced northward heat transport by the oceans. The clusters of ice cap expansion defined by moss kill dates are mirrored in an annually resolved Common Era record of ice cap dimensions in Iceland, suggesting this is a circum-North-Atlantic–Arctic climate signal for the Common Era. During the coldest century of the Common Era, 1780–1880 CE, ice caps mantled >11 000 km2 of north-central Baffin Island, whereas <100 km2 is glaciated at present. The peak Little Ice Age state approached conditions expected during the inception phase of an ice age and was only reversed after 1880 CE by anthropogenic alterations of the planetary energy balance.

Application of the Biolog EcoPlate™ technique for assessing the microbial metabolic diversity in moss profiles of continental Antarctica

Little is known about metabolic capabilities of microbial assemblages in continental Antarctic to utilize diverse carbon sources within moss profiles consisting of live, senescent, and dead moss tissues in different stages of decomposition. In the present study, microbial metabolic diversity was determined using Biolog EcoPlate™ for samples of Bryum pseudotriquetrum/B. archangelicum complex collected at five sites located in coastal outcrops of the Lützow-Holm Bay area (Queen Maud Land), East continental Antarctica, and effects of chemical, biological, and physical properties of the moss tissues were explored. The average well-color development, the number of substrates utilized, Simpson's diversity index and equitability of the microbial substrate utilization, and the utilization of carbohydrates, amino acids/amines, carboxylic acids, and polymers varied significantly among the five sites and among four layers of moss profiles. Principal component analysis showed that the utilization of L-asparagine, L-arginine, D-galacturonic acid, Tween 40, Tween 80, and D-mannitol mainly contributed to the variance in the microbial metabolic diversity between sites and moss profiles. The linear mixed models indicated that the relative content of recalcitrant organic components, the number of fungal species, and the water content of moss tissues affected the diversity of microbial utilization of carbon sources.

Ecological succession of fungal and bacterial communities in Antarctic mosses affected by a fairy ring disease.

We evaluated fungal and bacterial diversity in an established moss carpet on King George Island, Antarctica, affected by 'fairy ring' disease using metabarcoding. A total of 127 fungal and 706 bacterial taxa were assigned. Ascomycota dominated the fungal assemblages, followed by Basidiomycota, Rozellomycota, Chytridiomycota, Mortierellomycota and Monoblepharomycota. The fungal community displayed high indices of diversity, richness and dominance, which increased from healthy through infected to dead moss samples. A range of fungal taxa were more abundant in dead rather than healthy or fairy ring moss samples. Bacterial diversity and richness were greatest in healthy moss and least within the infected fairy ring. The dominant prokaryotic phyla were Actinobacteriota, Proteobacteria, Bacteroidota and Cyanobacteria. Cyanophyceae sp., whilst consistently dominant, were less abundant in fairy ring samples. Our data confirmed the presence and abundance of a range of plant pathogenic fungi, supporting the hypothesis that the disease is linked with multiple fungal taxa. Further studies are required to characterise the interactions between plant pathogenic fungi and their host Antarctic mosses. Monitoring the dynamics of mutualist, phytopathogenic and decomposer microorganisms associated with moss carpets may provide bioindicators of moss health.

Ecological analysis of rare and endangered lichen species included in the Red Book of the Chuvash Republic

The paper provides an ecological analysis of rare and endangered lichen species included in the Red Book of the Chuvash Republic. The new edition, published in 2020, includes information on 256 species of plants and fungi. The Red Book of the Chuvash Republic includes 30 species of rare and endangered lichen species, 14 species are included in the list of those which are subject to special attention and need constant monitoring in the natural environment. Biomorphological analysis has shown that rare lichen species belong to 3 types, 4 classes and 7 groups of life forms. The predominant species are bushy (bushy hanging group 11 species, bushy branching group 1 species, bushy erect group 1 species) and foliose (parted-lobed rhizoidal group 10 species, broad-bladed rhizoidal group 2 species) lichens. Ecological-substrate analysis has revealed that lichens included in the Red Book of the Chuvash Republic grow on 8 phorophytes (Tilia cordata, Quercus robur, Betula pendula, Salix cinerea, Pinus sylvestris, Picea abies, Abies sibirica, Populus tremula), on soil, on dead organic substrate and mosses. The greatest number of rare lichens was found on the bark of Tilia cordata, on the bark of Pinus sylvestris and on soil.

Taxonomic, functional, and phylogenetic diversity of fungi in a forest-tundra ecotone in Québec

We quantified the taxonomic, functional, and phylogenetic diversity of fungi associated with dead moss tissues and conifer needles in a forest-tundra ecotone in a sub-Arctic region, Quebec, Canada. We detected 615 operational taxonomic units, in total, of fungi in 84 families with 97% sequence similarity by metabarcoding the internal transcribed spacer 1 (ITS1) region of nuclear ribosomal DNA. Saprotrophs were the dominant functional guild. The results indicated the effects of host plant species and local environmental heterogeneity on fungal diversity in the cold region. Taxonomic and phylogenetic diversity indices of fungal communities were significantly greater in moss than in conifers. The greater phylogenetic diversity in moss was mainly attributable to the presence of families in Mucoromycota, compared to those in conifers, in which relatively closely related families of Dikarya were present. The taxonomic diversity was also related to local variations in vegetation and soil properties, suggesting that the local colonization and establishment of vegetation and the concomitant development of soil contributed to the taxonomic diversity of fungi. In contrast, functional diversity was not significantly affected by the host, vegetation, or soil properties, indicating that the fungal community members were relatively redundant in terms of the evaluated functional traits.

Ash application enhances decomposition of recalcitrant organic matter

Harvesting whole-tree biomass for biofuel combustion intensifies removal of nutrients from the ecosystem. This can be partly abated by applying ash from the combustion back to the system, as the ash is rich in nutrients. Ash is very alkaline and ash application raises soil pH, which in turn can stimulate microbial activity and thus decomposition and mineralization. Our aim was to test if ash induced decomposition activity was associated with enhanced turnover of recalcitrant, i.e. relatively old, organic pools. Two experiments were conducted in the same coniferous plantation after the application of 0, 3, 4.5 and 6 t ash ha−1, and 0, 3, 9, 15 and 30 t ash ha−1, respectively. We used natural abundance of 15N in mosses, mites and ectomycorrhizal fungi 26 months after ash application, as well as temporal variation in δ15N values of ectomycorrhizal fungi, as an indicator of decomposition of recalcitrant organic matter in the first experiment. Furthermore, in the second experiment we used measurements of extracellular manganese peroxidase activity almost 4 years after ash application as an indication of potential decomposition of lignin, an important component of recalcitrant organic matter.The δ15N signature increased significantly for ectomycorrhizal fungi, dead moss, Nothroid and Gamasida mites, and manganese peroxidase activity tended to increase, with increasing ash doses. This suggests that ash application stimulates turnover of recalcitrant organic matter, which can increase the available pool of nitrogen in the system. This will potentially enhance the fertilizer value of ash. However, the δ15N in ectomycorrhizal fungi tended to peak at 18 months after ash application, before decreasing, suggesting that the turnover of recalcitrant organic matter is reduced again with time.

Body size structure of oribatid mite communities in different microhabitats

ABSTRACTSize scaling phenomena occur on different levels, from organisms to ecosystems. In predictive ecology, empirical data on body size relation have been used for decades to explain large-scale temporal and spatial patterns. More recently, community ecologists have started to use abundance-weighted mean body sizes as a tool to predict changes in species assemblages along gradients in above-ground systems. In soil and litter systems, however, body size of individuals or the body size structure of communities have rarely been addressed in this way. Here we use community data of oribatid mites from different forest ground microhabitats (dead wood, moss, and litter) in combination with body size measurements to describe some basic body-size relationships for decomposer mites. Generally, we found that the community body size (measured as an abundance-weighted mean of all species) as well as size distribution of sexual and parthenogenetic oribatids differed across microhabitats. Furthermore, our results showed that the abundance of oribatid mites in fragmented (moss), but not in continuous (dead wood, litter) microhabitats, can be predicted by the community body size. All these differences might be explained by specific microhabitat conditions like pore size and food resource quality, but also by the dominance and competitive or facultative interactions among certain species in a particular sample or habitat. Additionally, our results bring renewed attention to body size as an important predictor for patterns, structure, and energy translocation in terrestrial forest soil food webs.

Evidence on the effectiveness of mosses for biomonitoring of microplastics in fresh water environment

Mosses are well known as biomonitors of fresh water for metal pollutants, but no studies were reported so far about their ability to intercept plastic particles, although this kind of pollution has become an urgent issue worldwide. In the present work, the interaction between the moss Sphagnum palustre L. cultured in vitro and polystyrene nanoparticles (NPs) was studied for the first time in a laboratory experiment, in the view of using moss transplants for detecting microplastics in fresh water environments. The ability of S. palustre to intercept and retain polystyrene, and the effects of vitality and post-exposure washing on NP retention by moss were tested. Fluorescence microscope observations showed that polystyrene NPs were retained by moss leaves in form of small (the most abundant fraction) and large aggregates. Particle count analysis highlighted that the number of particles increased while increasing the exposure time. Moreover, moss devitalization favored NP accumulation, likely because of cell membrane damages occurred in dead moss material. Post-exposure washing induced a loss of larger aggregates, suggesting that exposure time is a key point to be carefully evaluated in field conditions. These results encourage the use of S. palustre transplants for monitoring microplastics contamination of fresh water environments.

The importance of facilitative interactions on the performance of Colobanthus quitensis in an Antarctic tundra

AbstractAimsThe sign of interactions among plants in very harsh environments is under debate. The Antarctic tundra is one of the harshest environments on Earth and only two vascular plants (Deschampsia antarctica and Colobanthus quitensis) have successfully established natural populations. D. antarctica mostly establishes facilitative interactions with other species (mosses), but there is no information about the inter‐specific interactions established by C. quitensis. We assessed whether C. quitensis grows frequently associated with D. antarctica, and if D. antarctica neighbours have a positive effect on the survival, growth and photochemical efficiency of C. quitensis individuals.LocationKing George Island, Antarctic Peninsula.MethodsTo assess the spatial association among the two Antarctic vascular plants fifty 50 m × 50 cm quadrats were sampled on each of four different substrates: moss carpet areas; dead moss carpet areas dominated by D. antarctica; a transition zone between dead moss carpets and fellfields; and fellfields characterized by very poor vegetation cover. Infrared thermal images were taken to estimate whether growth associated with D. antarctica affected the foliar temperature of C. quitensis. The importance of D. antarctica neighbours on the growth, survival and photochemical efficiency of C. quitensis was evaluated with a neighbour removal experiment.ResultsThe number of C. quitensis individuals associated with D. antarctica was significantly higher than when growing alone in the moss carpet and the dead moss carpet, while in the transition zone there was a trend in that direction. C. quitensis individuals growing associated with D. antarctica were bigger than those growing alone in these three substrate types. In the fellfield site there were no significant differences, neither in the number nor the size of individuals when growing alone or associated with D. antarctica. Foliar temperature of C. quitensis individuals associated with D. antarctica was slightly (1.1°C) but significantly higher than in those growing alone. The growth, survival and photochemical efficiency of C. quitensis individuals with neighbours were higher than in individuals with neighbours removed.ConclusionsOur results indicate that D. antarctica has a facilitative effect on the growth, survival and photochemical efficiency of C. quitensis. Thus, facilitative interactions are present and are important in one of the harshest environments on Earth, although results from the fellfield site indicate that further research is needed.

Phytofiltration of arsenic by aquatic moss (Warnstorfia fluitans).

This work investigates whether aquatic moss (Warnstorfia fluitans) originating from an arsenic (As)-contaminated wetland close to a mine tailings impoundment may be used for phytofiltration of As. The aim was to elucidate the capacity of W.fluitans to remove As from arsenite and arsenate contaminated water, how nutrients affect the As uptake and the proportion of As adsorption and absorption by the moss plant, which consists of dead and living parts. Arsenic removal from 0, 1, or 10% Hoagland nutrient solution containing 0-100μM arsenate was followed over 192h, and the total As in aquatic moss after treatment was analysed. The uptake and speciation of As in moss cultivated in water containing 10μM arsenate or arsenite were examined as As uptake in living (absorption+adsorption) and dead (adsorption) plant parts. Results indicated that W.fluitans removed up to 82% of As from the water within one hour when 1μM arsenate was added in the absence of nutrients. The removal time increased with greater nutrient and As concentrations. Up to 100μM As had no toxic effect on the plant biomass. Both arsenite and arsenate were removed from the solution to similar extents and, independent of the As species added, more arsenate than arsenite was found in the plant. Of the As taken up, over 90% was firmly bound to the tissue, a possible mechanism for resisting high As concentrations. Arsenic was both absorbed and adsorbed by the moss, and twice as much As was found in living parts as in dead moss tissue. This study revealed that W.fluitans has potential to serve as a phytofilter for removing As from As-contaminated water without displaying any toxic effects of the metalloid.

Legacy effects of drought alters the aquatic food web of a northern boreal peatland

Abstract Compared to other temporary aquatic ecosystems, we know relatively little about how inundation frequency and duration (i.e. hydrologic regime) influences the structure of aquatic communities in northern peatlands. In this study, we examined patterns in nutrient availability and aquatic community structure during a natural flooding event in an Alaskan fen where water‐table position had been manipulated in three large‐scale experimental plots during previous years to simulate both drought (lowered water‐table treatment) and flooding (raised water‐table treatment) conditions relative to a control without manipulation. Although the natural flood disrupted the long‐term experimental manipulation, it provided an opportunity to evaluate how variation in past hydrologic regime influences nutrient dynamics and aquatic food web structure during periods of inundation in a northern boreal peatland. Despite similar water depth among experimental plots during the time of sampling (i.e. water was above the peat surface in all plots), water‐column nutrient concentrations were significantly greater in the drought treatment (where water table had been lowered during the previous growing season) compared to the raised water‐table treatment and the control. Algal production increased with enhanced nutrient availability across all water‐table treatments and was most elevated following the rewetting of dry sediments in the drought treatment. Consumer biomass (heterotrophic bacteria and macroinvertebrates) increased with algal production and was significantly greater in the drought treatment compared to the raised water‐table treatment and the control. Consumer biomass decreased into the second year of constant inundation as algal production was constrained by reduced nutrient availability. Stable isotope analysis (13C and 15N) showed that elevated levels of periphyton (i.e. the intact biofilm) associated with enhanced nutrient availability promoted energy transfer to higher trophic levels (grazers and predators) rather than living or dead mosses or vascular plant material. Consumption of algal material by grazers altered the size and composition of the algal community. The algal community shifted from coccoid (edible) to filamentous (inedible) growth forms with increased grazer abundance in the drought treatment, possibly owing to selective grazing. Conversely, there was a similar proportion of edible and inedible taxa in the control and raised treatments where grazers were lower in abundance. Our results show that the legacy effects of drought can regulate aquatic community structure in northern peatlands. Within a predictive context, our findings suggest that conditions of more variable hydrology expected with climate change (i.e. increased frequency of drought) occurring across northern latitudes will promote energy flow to higher trophic levels by releasing nutrient constraints on microalgae during periods of inundation.

Rare Moss-Built Microterraces in a High-Altitude, Acid Mine Drainage-Polluted Stream (Cordillera Negra, Peru).

The Rio Santiago in the Cordillera Negra of Peru is severely contaminated by acid mine drainage in its headwaters. In a strongly acid stream, at about 3800 m above sea level (masl), microterraces were found with terrace walls built up of dead moss, with encrustations and interstitial fine, creamy sediment. The stream water was turbid due to the presence of similar suspended sediment, which also occurred as a thin basal layer in inter-rim basins. The moss was identified as the rare bryophyte Anomobryum prostratum (Müll. Hal.) Besch. Chemical and mineralogical analyses show that green, living parts of the moss are gradually coated by Al/Fe (hydr)oxides, inducing their senescence and death. The necromass is covered by creamy crusts through precipitation of schwertmannite-type material from the stream water and simultaneous ‘capture’ of fine sediment. The latter consists of a mixture of precipitate and fine detrital primary minerals. These processes are held responsible for the formation of the microterraces, which regarding their composition and environment seem to be unique. Remarkable is the high As content of the creamy crusts and sediment, attributed to strong sorption of As, whereas its solute concentration is relatively low. This calls for more attention to suspended fine sediment in the assessment of environmental risks of stream water use. Lastly, the results raise serious doubts about the use of aquatic bryophytes as bioindicator for chemical pollution in acid mine drainage-polluted streams.Electronic supplementary materialThe online version of this article (doi:10.1007/s11270-015-2390-x) contains supplementary material, which is available to authorized users.

Zn isotope fractionation in a pristine larch forest on permafrost-dominated soils in Central Siberia

Stable Zn isotopes fractionation was studied in main biogeochemical compartments of a pristine larch forest of Central Siberia developed over continuous permafrost basalt rocks. Two north- and south-oriented watershed slopes having distinctly different vegetation biomass and active layer depth were used as natural proxy for predicting possible future climate changes occurring in this region. In addition, peat bog zone exhibiting totally different vegetation, hydrology and soil temperature regime has been studied.The isotopic composition of soil profile from Central Siberia is rather constant with a δ66Zn value around 0.2‰ close to the value of various basalts. Zn isotopic composition in mosses (Sphagnum fuscum and Pleurozium schreberi) exhibits differences between surface layers presenting values from 0.14 to 0.2‰ and bottom layers presenting significantly higher values (0.5 – 0.7‰) than the underlain mineral surface. The humification of both dead moss and larch needles leads to retain the fraction where Zn bound most strongly thus releasing the lighter isotopes in solution and preserving the heavy isotopes in the humification products, in general accord with previous experimental and modeling works [GCA 75:7632–7643, 2011].The larch (Larix gmelinii) from North and South-facing slopes is enriched in heavy isotopes compared to soil reservoir while larch from Sphagnum peatbog is enriched in light isotopes. This difference may result from stronger complexation of Zn by organic ligands and humification products in the peat bog compared to mineral surfaces in North- and South-facing slope.During the course of the growing period, Zn followed the behavior of macronutrients with a decrease of concentration from June to September. During this period, an enrichment of larch needles by heavier Zn isotopes is observed in the various habitats. We suggest that the increase of the depth of rooting zone, and the decrease of DOC and Zn concentration in soil solution from the root uptake zone with progressively thawing soil could provoke heavy isotopes to become more available for the larch roots at the end of the vegetative season compared to the beginning of the season, because the decrease of DOC will facilitate the uptake of heavy isotope as it will be less retained in strong organic complexes.

The spatial structures of hypolithic communities in the Dry Valleys of East Antarctica

Hypolithic communities represent important reservoirs of microbial life in hyper-arid deserts. A number of studies on the diversity and ecology of these communities from different geographic areas have been reported in the past decade, but the spatial distribution of the different components of these communities is still not understood. Moss- and cyanobacteria-dominated hypolithic community morphotypes from Miers Valley (McMurdo Dry Valleys, East Antarctica) were analyzed by electron microscopy in order to characterize the microscale spatial structure. The two communities showed a high degree of internal organization, but differing according to the biological composition. In moss-dominated hypoliths, the moss plantlets are intermixed with mineral fragments of soil origin. However, in cyanobacteria-dominated hypoliths, a layered spatial organization was structured by filamentous cyanobacteria and associated extracellular polymeric components. While moss cells were lacking in cyanobacteria-dominated communities, biofilms formed by cyanobacteria and heterotrophic bacteria were observed in both community morphotypes. The water-holding capacity of both live and dead moss cells and the associated organic matrix, together with the protective properties of the extracellular polymeric substances, could facilitate the survival and activity of these communities. Similar structural strategies can favor the survival of microbial communities in different extreme environments.

Effects of post‐windthrow salvage logging on microsites, plant composition and regeneration

AbstractQuestionsHow does windthrow influence plant diversity and composition as well as regeneration and microsite characteristics? What are the consequences of post‐windthrow salvage logging on these key attributes?LocationEastern black spruce–moss forest,Quebec,Canada.MethodsA total of 92 plots were sampled, each with a radius of 11.28 m; 49 of these plots were salvaged while 43 were unsalvaged. Regeneration density, plant diversity and seedbeds were characterized. We tested the effect of microtopography and windthrow severity on species richness and Shannon diversity index for salvaged and unsalvaged windthrows using a mixed model. Partial redundancy analysis (RDA) determined which environmental and stand characteristics were most important in explaining differences in plant species and forest floor types among the treatments. The effects of treatments (salvaged and unsalvaged windthrows), microtopography attributes, windthrow severity and regeneration species on seedling and sapling abundance were tested using a linear mixed model.ResultsSalvaged windthrow, with a large proportion of skid trails, dead mosses andSphagnum, had a lower degree of seedbed heterogeneity. Also, some understorey species present in the unsalvaged ecosystem were absent from the salvaged windthrow.Sphagnumand other moss species were clearly associated with the unsalvaged treatment. White birches were positively associated with mound microtopography in the unsalvaged windthrow.ConclusionFrom an ecosystem‐based forest management perspective, natural post‐windthrow understorey conditions and microsite heterogeneity can be in part maintained in salvaged cut blocks by incorporating retention patches that include downed and standing dead wood and living trees of diverse sizes. These steps should favour plant regeneration and augment diversity for salvage logging after wind disturbance.

Effect of copper stress on cup lichens Cladonia humilis and C. subconistea growing on copper-hyperaccumulating moss Scopelophila cataractae at copper-polluted sites in Japan

We investigated lichen species in the habitats of the copper (Cu)-hyperaccumulating moss Scopelophila cataractae and found that the cup lichens Cladonia subconistea and C. humilis grow on this moss. We performed X-ray fluorescence and inductively coupled plasma mass (ICP-MS) analysis of lichen samples and measured the visible absorption spectra of the pigments extracted from the samples to assess the effect of Cu stress on the cup lichens. The chlorophyll a/b ratio and degradation of chlorophyll a to pheophytin a were calculated from the spectral data. X-ray fluorescence analysis indicated that Cu concentrations in cup lichens growing on S. cataractae were much higher than those in control samples growing on non-polluted soil. Moreover, Cu microanalysis showed that Cu concentrations in parts of podetia of C. subconistea growing on S. cataractae increased as the substrate (S. cataractae) was approached, whereas those of C. humilis growing on S. cataractae decreased as the substrate was approached. This reflects the difference in the route of Cu ions from the source to the podetia. Furthermore, ICP-MS analysis confirmed that C. subconistea growing on S. cataractae was heavily contaminated with Cu, indicating that this lichen is Cu tolerant. We found a significant difference between the visible absorption spectra of pigments extracted from the Cu-contaminated and control samples. Hence, the spectra could be used to determine whether a cup lichen is contaminated with Cu. Chlorophyll analysis showed that cup lichens growing on S. cataractae were affected by Cu stress. However, it also suggested that the areas of dead moss under cup lichens were a suitable substrate for the growth of the lichen. Moreover, it suggested that cup lichens had allolepathic effects on S. cataractae; it is likely that secondary metabolites produced by cup lichens inhibited moss growth.

A STUDY OF SOLUTIONS TO PREVENT THE EROSION OF THE MOSS GROWING ON ARCHITECTURES OF HUE IMPERIAL CITADEL

Background: The erosion of mosses on the surface of Hue imperial citadel has caused a lot of harm and is currently an urgent problem to be solved. Objectives:1. Identifying some moss species growing on Hue relics. 2. Determining the cause of slipperiness and the living environment mosses. 3. Finding a solution to limit the intrusion of the mosses. Methods: The methods are: identifying scientific name by comparing patterns, identify mucus, pH measurement and evaluation of the effects of certain chemicals on the growth of mosses in the laboratory. Result: The moss species that develop popularly in Hue relics is Funaria hygrometrica, Bryum apiculatum, Trichostomum orthodontum, Fissidens lycopodioides. Funaria hygrometrica is the most popular moss. The cause of the slipperiness is mucus in moss cells released outside the moss after death. Mosses grow well in moist environments, clear and slightly acidic surface. After two days assessing the effect of citric acid 18%, 15%, 10% and 7% NaHCO3, 5%, 3% on the growth of moss, the mosses all died completely. Since then identified two types of chemicals have been found to completely dead moss, inexpensive, environmentally friendly and does not affect the surface of architectures are citric acid 10% solution and NaHCO3 3% solution. Keywords: The moss erosion, Funaria hygrometrica, mucus, citric acid, NaHCO3 Key words: The moss erosion, Funaria hygrometrica, mucus, citric acid, NaHCO 3

Oven-dried mosses as tools for trace element detection in polluted waters: A preliminary study under laboratory conditions

The concentration of 11 trace elements, plus Ca, Mg, Na and K was measured in moss bags of living and dead (oven-dried at 105°C) Platyhypnidium riparioides after a 1-week exposure to tap water, and to 0.21, 1.0, 2.5 and 4.0 μM solutions under laboratory conditions, with the aim of (1) observing the accumulation curves and (2) performing a statistical comparison in element concentrations. Uptake occurred both in living and in dead mosses following similar patterns in the two materials: a linear uptake was observed for Cd and Ni, a saturation curve for As, Cu, Hg and Pb, an unclear trend for Al and Mn and a trend leading to a maximum for Cr and Fe. An evident efflux of K indicated alterations in cell membrane permeability in living mosses and cellular damage in dead mosses. Living mosses accumulated higher concentrations of Cr (+4/+49%) and Mn (+124/+216%), while dead mosses accumulated higher concentrations of Cd (+13/+50%), Cu (+26/+51%), Ni (+22/+139%) and Zn (+22/+63%). Dead mosses maintained a considerable uptake efficiency for several trace elements, and sometimes even increased it as compared with living mosses, thus proving to be suitable for standard kits.

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.