Epiphyte Community Structure Research Articles

Effects of epibiotic bacteria on leaf growth and epiphytes of the seagrass Posidonia oceanica

MEPS Marine Ecology Progress Series Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout the JournalEditorsTheme Sections MEPS 456:21-27 (2012) - DOI: https://doi.org/10.3354/meps09672 Effects of epibiotic bacteria on leaf growth and epiphytes of the seagrass Posidonia oceanica D. Celdrán1,*, E. Espinosa2, A. Sánchez-Amat2, A. Marín1 1Departamento de Ecología e Hidrología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain 2Departamento de Genética y Microbiología, Facultad de Biología, Universidad de Murcia, 30100 Murcia, Spain *Email: manueldavid.celdran@um.es ABSTRACT: Beneficial effects of microorganisms on plant productivity are well known from terrestrial ecosystems, but no corresponding effects on marine plants have been described. We tested the hypothesis that the bacteria Marinomonas posidonica and M. mediterranea, which have been described as a forming component of the microbiota on Posidonia oceanica, influence leaf growth and epiphytic communities of this seagrass. We carried out 4 treatments: (1) seedlings inoculated with M. mediterranea or (2) M. posidonica and seedlings to which (3) sterilized seawater (sterile control) or (4) fresh seawater (field control) was added. Two experiments were performed: a growth assay in the laboratory under sterile conditions measuring leaf area after 3 mo, and an epiphyte assay in which the seedlings were transferred to the field. Leaves were sampled after 3 mo to analyse the community structure of epiphytes. The growth experiment showed that inoculation with M. posidonica enhanced leaf growth of P. oceanica compared with the controls to which no bacterial strain was added. In contrast, inoculation with M. mediterranea did not stimulate leaf growth. Likewise, inoculation with M. posidonica induced changes in epiphyte structure and can be expected to have a regulatory effect on macroepiphyte structure. KEY WORDS: Marinomonas spp. · Viability · Microbiota · Epiphytic communities · Biofouling Full text in pdf format PreviousNextCite this article as: Celdrán D, Espinosa E, Sánchez-Amat A, Marín A (2012) Effects of epibiotic bacteria on leaf growth and epiphytes of the seagrass Posidonia oceanica. Mar Ecol Prog Ser 456:21-27. https://doi.org/10.3354/meps09672 Export citation RSS - Facebook - Tweet - linkedIn Cited by Published in MEPS Vol. 456. Online publication date: June 07, 2012 Print ISSN: 0171-8630; Online ISSN: 1616-1599 Copyright © 2012 Inter-Research.

The Conservation Value of Secondary Forests for Vascular Epiphytes in Central Panama

AbstractSecondary forests that develop following land abandonment could compensate for the losses of diversity and structure that accompany deforestation of old‐growth forests in tropical regions. Whether secondary forests can harbor similar species richness, density, and composition of old‐growth forests for vascular epiphytes remains largely unknown for secondary forests older than 50 yr. We examined community structure (species richness, density, and species composition) of vascular epiphytes in older secondary forests between 35 and 115 yr after land abandonment and nearby old‐growth forests to determine if the community structure of epiphytes in secondary forests approaches that of old‐growth forests over time. The recovery of epiphyte species richness was rapid with 55‐year‐old forests containing 65 percent of old‐growth epiphyte species richness. Secondary forest epiphyte communities were found to be statistically nested within secondary forests older in age and within old‐growth forests. Similarity of epiphyte communities to old‐growth forests increased to 75 percent, 115 yr after abandonment. This study suggests that secondary forests will likely recover old‐growth epiphyte richness and composition given enough time. Epiphyte densities did not recover quickly with 55‐year‐old forests having 14 percent and 115‐year‐old forests having only 49 percent of the density of old‐growth forest epiphytes. The low density of epiphytes in secondary forests could impact rainforest diversity and function. We conclude that in less than 115 yr, although secondary moist forests have high conservation value for some aspects of community structure, they are unlikely to compensate biologically for the loss of diversity and ecosystem function that high epiphyte densities provide.

The effect of plant density on epiphytic macroinvertebrates associated with a submerged macrophyte, Lagarosiphon ilicifolius Obermeyer, in Lake Kariba, Zimbabwe

The effect of variations in the density of a submerged macrophyte, Lagarosiphon ilicifolius, on epiphytic macroinvertebrate community structure in the shallow waters of a sheltered bay of Lake Kariba were investigated. The body size class distributions of a mayfly, Cloeon (Ephemeroptera: Baetidae), and the damselfly family, Coenagrionidae, were also assessed with respect to variation in vegetation density. Macroinvertebrates were sampled from low-, moderate- and high-density beds of L. ilicifolius. There were no significant differences in individual taxon and total macroinvertebrate abundances, macroinvertebrate richness and diversity with respect to vegetation density. In all three density categories the functional feeding group (FFG) composition was dominated by collector-gatherers and collector-filterers. The abundance of the two FFGs did not change significantly within each, as well as among, the three vegetation-density categories (ANOVA, p > 0.05). The largest size class of Cloeon occurred only in high-density beds, whereas the largest coenagrionid individuals were obtained from low- and moderate-density beds and were absent from high-density beds. The results suggest that variation in the density of Lagarosiphon does not affect epiphytic macroinvertebrate community structure, but does affect body-size distributions of macroinvertebrate taxa, probably by affecting predator-prey interactions.

Isolation affects tree-scale epiphytic lichen community structure on New Zealand mountain beech trees

Question: Is epiphytic lichen community structure significantly affected by isolation from source community? Location: Foothills of the Southern Alps, South Island, New Zealand. Methods: Epiphytic lichen richness and environmental variables were measured on 382, young Nothofagus solandri var. cliffortioides (Hook. f.) Poole (mountain beech) trees that had recently colonized grassland adjacent to a forest remnant. Richness and the presence of individual lichen taxa were modelled as a function of isolation from the forest fragment, tree size and other habitat conditions. Results: Richness of epiphytic lichen communities was negatively related to tree isolation, although this effect was much smaller than the effects of tree size and other local (tree-scale) habitat conditions. Different lichen taxa responded in different ways to isolation, area effects and local habitat conditions. Conclusions: This study shows that many epiphytic lichens on mountain beech are limited in their ability to colonize new substrate, even over distances of less than 1 km, which may be due to limitation in dispersal and/or establishment. Lichens are greatly influenced by local habitat conditions, such as tree size, and in this particular environment their negative interaction with sooty moulds is an important driver of community structure.

Seasonal dynamics of the structure of epiphytic yeast communities

The seasonal dynamics of the species structure of epiphytic yeasts on the leaves and in the flowers of 25 plant species was studied throughout the period of their vegetation. It was shown that, on average for the vegetation period, the composition of epiphytic yeast communities was nonspecific. The same species of epiphytic yeasts dominated on different plant species, irrespective of their taxonomic identity and ecological peculiarities. However, different species of yeasts exhibited different types of seasonal dynamics of relative abundance. Therefore, a combination of the dynamics of yeast species and the ontogenetic cycles of plants creates a pattern of the dynamics of the epiphytic yeast population, which is unique for each plant species. The species diversity of yeasts on the leaves of a plant is determined by the duration of its ontogenetic cycle: the longer the vegetation of a plant, the higher the diversity of the epiphytic yeasts population. The greatest diversity of epiphytic yeasts was revealed on the leaves of perennial hygrophytes and mesophytes; the minimal diversity, on ephemeroids and annuals with a short ontogenetic cycle.

Early warning response of Posidonia oceanica epiphyte community to environmental alterations (Ligurian Sea, NW Mediterranean)

The epiphyte community structure of the Posidonia oceanica leaves in three impacted meadows occurring in urbanised coastal areas was contrasted with that observed in three meadows located within Marine Protected Areas in the Ligurian Sea. Samplings were carried out in two distinct periods, at the beginning and at the end of the summer season, in order to individuate early changes in the epiphyte community structure. Differently from the descriptors commonly adopted for evaluating the health status of P. oceanica ecosystem, the epiphyte community structure was able to detect alterations in the water quality already after 4 months. The impacted meadows showed an immature epiphyte community characterised by large development of brown algae. Leaf P. oceanica epiphytes are, thus, proposed as appropriate biological quality elements (BQEs) able to show early responses to environmental alterations and they should be included in the monitoring programs for the conservation and the management of coastal areas.

A hierarchical framework for investigating epiphyte assemblages: networks, meta‐communities, and scale

Epiphytes are an important component of many forested ecosystems, yet our understanding of epiphyte communities lags far behind that of terrestrial-based plant communities. This discrepancy is exacerbated by the lack of a theoretical context to assess patterns in epiphyte community structure. We attempt to fill this gap by developing an analytical framework to investigate epiphyte assemblages, which we then apply to a data set on epiphyte distributions in a Panamanian rain forest. On a coarse scale, interactions between epiphyte species and host tree species can be viewed as bipartite networks, similar to pollination and seed dispersal networks. On a finer scale, epiphyte communities on individual host trees can be viewed as meta-communities, or suites of local epiphyte communities connected by dispersal. Similar analytical tools are typically employed to investigate species interaction networks and meta-communities, thus providing a unified analytical framework to investigate coarse-scale (network) and fine-scale (meta-community) patterns in epiphyte distributions. Coarse-scale analysis of the Panamanian data set showed that most epiphyte species interacted with fewer host species than expected by chance. Fine-scale analyses showed that epiphyte species richness on individual trees was lower than null model expectations. Therefore, epiphyte distributions were clumped at both scales, perhaps as a result of dispersal limitations. Scale-dependent patterns in epiphyte species composition were observed. Epiphyte-host networks showed evidence of negative co-occurrence patterns, which could arise from adaptations among epiphyte species to avoid competition for host species, while most epiphyte meta-communities were distributed at random. Application of our "meta-network" analytical framework in other locales may help to identify general patterns in the structure of epiphyte assemblages and their variation in space and time.

Development and functional structure of epiphytic nematode communities on the submerged macrophyte Ceratophyllum demersum in Lake Sakadaš, Kopački Rit, Croatia

AbstractThe structural and functional diversity of epiphytic nematodes associated with the submerged macrophyte species, Ceratophyllum demersum, were investigated from July to September 2004 at three stations in the floodplain lake, Lake Sakadaš, Croatia. At stations I and II, C. demersum was dominant in the macrophyte patches. At station III, Myriophyllum spicatum was the dominant macrophyte species. When analysis of nematode species composition was done by grouping species with decreasing abundance, a community structure was evident on macrophytes that grew in different parts of the lake. When the abundance of nematodes was taken into account, C. demersum, which grew in different parts of the lake, was not associated with a unique nematode functional structure, and different trophic groups of nematodes were dominant at different stations. Eutobrilus nothus was the dominant nematode species for station I and chewers were the dominant functional group. Eutobrilus nothus, Eumonhystera sp. 1 and Eumonhystera filiformis vulgaris group were abundant nematode species for station II and consequently chewers and detritus feeders dominated at different periods of the investigation. Nematodes from station III were characterised by the highest nematode abundance where Chromadorina bioculata was the dominant species, and epistrate feeders were the dominant functional group. A part of our previously published results was reanalysed in this paper to enable comparison of nematode communities established on C. demersum with those developed on M. spicatum. There was no difference in the nematode functional structure between macrophyte species at the same station when the abundance of dominant species was taken into account, i.e., the same trophic structure was established.

Spatial structure of epiphytic yeast communities on fruits of Sorbus aucuparia L.

The subject of this research is epiphytic yeast communities that form on the surface of Sorbus aucuparia. The object is to make quantitative assessment of the yeast communities' differentiation of the same but distant substratum. Results of the factor variance nidicolous analysis demonstrated that with increase in distances, there are increases in the variation of total number and relative abundance of the dominant yeast communities. The average similarity between groups of single fruits (Sorensen's Quotient of Similarity) regularly decreased with distance. The results demonstrate that the number and structure of separate yeast groups depend not only on ecological factors but also on proximity to other communities. Such aggregation in the distribution of the microorganisms' species caused by migration and colonial resettlement should be taken into account when analyzing their diversity in natural habitats.

NUTRIENT EFFECTS ON SEAGRASS EPIPHYTE COMMUNITY STRUCTURE IN FLORIDA BAY(1).

A field experiment was employed in Florida Bay investigating the response of seagrass epiphyte communities to nitrogen (N) and phosphorus (P) additions. While most of the variability in epiphyte community structure was related to uncontrolled temporal and spatial environmental heterogeneity, P additions increased the relative abundance of the red algae-cyanobacterial complex and green algae, with a concomitant decrease in diatoms. When N was added along with P, the observed changes to the diatoms and the red algae-cyanobacterial complex were in the same direction as P-only treatments, but the responses were decreased in magnitude. Within the diatom community, species relative abundances, species richness, and diversity responded weakly to nutrient addition. P additions produced changes in diatom community structure that were limited to summer and were stronger in eastern Florida Bay than in the western bay. These changes were consistent with well-established temporal and spatial patterns of P limitation. Despite the significant change in community structure resulting from P addition, diatom communities from the same site and time, regardless of nutrient treatment, remained more similar to one another than to the diatom communities subject to identical nutrient treatments from different sites and times. Overall, epiphyte communities exhibited responses to P addition that were most evident at the division level.

Recent literature on lichens—213

Affeld, K., J. Sullivan, S. P. Worner & R. K. Didham. 2008. Can spatial variation in epiphyte diversity and community structure be predicted from sampling vascular epiphytes alone? Journal of Biogeography 35(12): 2274–2288. [Study in temperate rain forest of South Island, New Zealand, on epiphytes of Metrosideros robusta trees. Lichens ranged from 10–18% of the epiphytic flora. ‘‘Although we found some evidence that vascular plant seedling establishment was linked to the presence of lichens and the biomass of nonliving components in the epiphyte mats, there was no correlation in the spatial patterning or determinants of species richness between non-vascular and vascular plants.’’ There is no listing of the lichen species encountered.] Aptroot, A. & L. Sparrius. 2008. Crustose Roccellaceae in the Galapagos Islands, with the new species Schismatomma spierii. The Bryologist 111(4): 659–666. [Treatment of 24 spp. (many new records for the Galapagos and Ecuador); key. New: S. spierii n.sp. on coastal and inland trees. ‘‘Lecanographa laingiana is reported for the first time from the New World.’’ The genus Opegrapha was not included in this study.] Armaleo, D., Y. Zhang & S. Cheung. 2008. Light might regulate divergently depside and depsidone accumulation in the lichen Parmotrema hypotropum by affecting thallus temperature and water potential. Mycologia 100(4): 565–576. [A direct correlation was observed between the yearly amount of light reaching the lichen and the amount of atranorin. In contrast, the amount of norstictic acid decreased with increasing light.] Benatti, M. N. & M. P. Marcelli. 2007. Generos de fungos liquenizados dos manguezais do sul-sudeste do Brasil, com enfoque no manguezal do Rio Itanhaem, Sao Paulo. Acta Botanica Brasilica 21(4): 863–878. [Treatment of 81 genera (including a key) of lichens from mangrove forests in the region. In Portuguese with English abstract.] ——— & ———. 2008. Especies de Parmotrema (Parmeliaceae, Ascomycetes liquenizados) com maculas reticulares do litoral centro-sul do estado de Sao Paulo, Brasil. Hoehnea 35(1): 75–90. [Treatment (with key) of 6 spp. previously placed in the genus Rimelia. In Portuguese with English summary.] Berger, F. & A. Aptroot. 2008. Bactrospora flavopruinosa, a new lichen species from Bermuda. Lichenologist 40(6): 543–547. [New: B. flavopruinosa n.sp. from decorticated trunk of Juniperus bermudiana.] Bielczyk, U. 2005. Porosty w Tatrach. Pamietnik Polskiego Towarzystaw Tatrzanskiego [Memoir of the Polish Tatra Society] 14: 7–18. [General article on lichens of the Tatra Mountains, Poland. In Polish.] Bostock, P. & A. Holland. 2008. Appendix VIII: New names and taxa for Queensland plants, algae, lichens, bryophytes and fungi. July 2006 to June 2007. Pages 41–54. In A. Holland & P. Postock (eds.), Queensland Herbarium Achievements 2006–2007. Environmental Protection Agency, The State Government of Queensland. [Brief compiled report including 20 lichen spp.] Botting, R. S., J. Campbell & A. L. Fredeen. 2008. Contrasting arboreal and terrestrial macrolichen and bryophyte communities in old-growth sub-boreal forests of central British Columbia. The Bryologist 111(4): 607–619. [Authors analyzed biomass and nitrogen content in 71 spp. of macrolichens and 47 spp. of bryophytes in the study area NE of Prince George. ‘‘In total, terrestrial and arboreal lichens and bryophytes represented 20–39 kg N ha in this old-growth sub-boreal spruce ecosystem.’’] Bowker, M. A., G. W. Koch, J. Belnap & N. C. Johnson. 2008. Nutrient availability affects pigment production but not growth in lichens of biological soil crusts. Soil Biology and Biochemistry 40(11): 2819–2826. [Experiments with Collema tenax. ‘‘Although Mn fertilization does not appear likely to increase photosynthesis or growth of Collema, it could have a role in survivorship during environmentally * The cumulative database for this series is available in searchable form on the World Wide Web at http://www.nhm.uio.no/botanisk/bot-mus/ lav/sok_rll.htm. I owe special thanks to Bill Buck for providing copies of papers by other authors, which were otherwise unavailable to me, and to the cooperating authors who send reprints or electronic versions of their works to me for inclusion in this series.

Can spatial variation in epiphyte diversity and community structure be predicted from sampling vascular epiphytes alone?

AbstractAim Non‐vascular epiphytes have been largely ignored in studies examining the biotic and abiotic determinants of spatial variation in epiphyte diversity. Our aim was to test whether the spatial patterning of species richness, biomass and community composition across geographic regions, among trees within regions, and among branches within trees is consistent between the vascular and non‐vascular components of the temperate rain forest flora.Location Coastal lowland podocarp‐broadleaved forests on the west coast of the South Island of New Zealand.Methods We collected single samples (30 × 25 cm) from 96 epiphyte assemblages located on the inner branches of 40 northern rata (Metrosideros robusta) trees. For each sample, branch characteristics such as branch height, branch diameter, branch angle, branch aspect, and minimum and maximum epiphyte mat depth were recorded. The biomass for each individual epiphyte species was determined.Results Northern rata was host to a total of 157 species, comprising 32 vascular and 125 non‐vascular species, with liverworts representing 41% of all species. Within epiphyte mats, the average total organic biomass of 3.5 kg m−2 of branch surface area consisted largely of non‐living biomass and roots. Vascular and non‐vascular epiphytes showed strikingly different spatial patterns in species richness, biomass and composition between sites, among trees within sites, and among branches within trees, which could not be explained by the branch structural characteristics we measured. The two plant groups had no significant association in community composition (r = 0.04, P = 0.08). However, the species richness of vascular plant seedlings was strongly linked to the presence/absence of lichens.Main conclusions Non‐vascular plants contributed substantially to the high species richness and biomass recorded in this study, which was comparable to that of some tropical rain forests. High variability in community composition among epiphyte mats, and very low correlation with any of the environmental factors measured possibly indicate high levels of stochasticity in seed or spore colonization, establishment success or community assembly among branches in these canopy communities. Although we found some evidence that vascular plant seedling establishment was linked to the presence of lichens and the biomass of non‐living components in the epiphyte mats, there was no correlation in the spatial patterning or determinants of species richness between non‐vascular and vascular plants. Consequently, variation in total epiphyte biodiversity could not be predicted from the measurement of vascular plant diversity alone, which highlights the crucial importance of sampling non‐vascular plants when undertaking epiphyte community studies.

Epiphyte communities on redwood (Sequoia sempervirens) in northwestern California

We used rope techniques to access epiphyte communities on nine large and structurally complex redwoods (Sequoia sempervirens) occupying old-growth forest reserves of northwestern California. All species of epiphytic lichens, bryophytes and vascular plants were recorded, biomass of dominant vascular epiphytes (Polypodium scouleri and Vaccinium ovatum) was quantified, and tree crowns were mapped to estimate substrate surface areas. We employed a flexible, plot-based sampling regime defined by available microhabitats within height strata to search for epiphytes. All substrates were examined, including tree surfaces, canopy soils and perennially exposed surfaces of epiphytic vascular plants as well as forest floor vegetation, woody debris and terrestrial soils beneath the redwood crowns. Combined arboreal and terrestrial search efforts revealed 282 species, including 183 lichens, 50 bryophytes and 49 vascular plants. Beta diversities for plots aggregated by floristic group, stratum and substrate type were generally high, indicating a large proportion of infrequent species. Indirect ordination analysis suggested that an environmental gradient from exposed to sheltered habitats was the strongest factor controlling epiphyte community structure. Floristic groups, strata and substrates were highly segregated along the dominant compositional gradient. Chlorolichens, upper crown strata and redwood foliage occupied one end, while vascular plants, forest floor strata and terrestrial woody debris occupied the other end of the gradient. Indicator Species Analyses revealed that many species expressed affinities for particular substrates, including live vs. dead foliage, bark of small vs. large branches and limbs, bark of upper vs. lower surfaces of large limbs, bark of large trunks, bare wood, bryophyte mats, soils, non-redwood stems and terrestrial woody debris. Cluster Analysis identified seven groups of species with similar patterns of distribution across height strata and substrate types. Correlations between tree structure and species distribution suggested that structural complexity promoted epiphyte diversity within height strata. Surface areas of small live trunks, limbs and dead trunks were the best predictors of lichen species richness, Polypodium scouleri biomass and Vaccinium ovatum biomass, respectively. At least one new species (Calicium sp. nov.) was discovered, and two species (Buxbaumia piperi, Icmadophila ericetorum) normally restricted to terrestrial habitats were found as canopy epiphytes for the first time.

Structure and Ordination of Epiphytic Invertebrate Communities of Four Coastal Wetlands in Green Bay, Lake Michigan

Epiphytic macroinvertebrate communities of four coastal wetlands of Green Bay, Lake Michigan were compared by taxonomic composition, feeding group composition, and environmental influences using Bray-Curtis ordination. Ordination scores from the most sheltered oligotrophic site, Portage Marsh, were distinct from the eutrophic, exposed sites located in middle and lower Green Bay— Seagull Bar, Little Tail Point, and Dead Horse Bay. Epiphyton chlorophyll a, phytoplankton chlorophyll a, and specific conductance strongly correlated to the ordination axes, indicating the trophic gradient within Green Bay was a primary environmental influence. The feeding group compositions at the sites were consistent with the type and abundance of food available. Portage Marsh is a scraper-shredder system, with macroinvertebrates feeding mainly on epiphyton and coarse particulate detritus. Dead Horse Bay and Little Tail Point are collector systems, sustained by phytoplankton and fine particulate organic matter. Seagull Bar is intermediate in trophic position along the ordination axes, but more closely resemble the latter two sites. The type and abundance of food resources available to these invertebrate communities are influenced by wave exposure, light attenuation, nutrient levels, and algae levels of the littoral and pelagial waters. Macroinvertebrate communities were sensitive to shifts in food resources, which generated shifts in trophic structure.

Edge effects on epiphytic communities in a Mediterranean Quercus pyrenaica forest

AbstractQuestion: What are the edge effect responses of epiphytic lichen communities in Mediterranean Quercus pyrenaica forest?Location: Central Spain.Methods: We established ten transects perpendicular to a road dissecting a well conserved remnant of Q. pyrenaica forest into two sections. Transects extended from the forest/road edge to 100 m into the forest. Data were collected from seven plots in each transect at different distances from the edge. Variables were grouped into stand scale variables (distance to edge, number of trees per plot, mean diameter per plot, irradiance) and tree scale variables (diameter and height of sampled trees, aspect of the sampled square and relative height of the square). We used General Mixed Linear Models and constrained ordination techniques to test the hypothesis that the spatio‐temporal heterogeneity of light and water controls the occurrence of lichens and bryophytes along the edge‐interior gradient in the Q. pyrenaica forest.Results: Microclimatic parameters vary in a non‐linear way; edge and interior stands showed the most divergent and extreme values. Although the micro‐environment within Mediterranean forests is heterogeneous, interior conditions are apparently suitable for the performance of some specific forest epiphytes. Consequently, species richness does not show significant differences along the gradient. Total epiphytic cover increases towards the forest interior, but distance to the edge together with other predictors at the tree scale (aspect and height of the square) are the most relevant predictors for the composition and structure of these communities.Conclusions: Composition and structure of epiphytic communities in a Mediterranean semi‐deciduous forest are affected by the edge between the forest and the road constructed. Since some extremely rare lichens only occur at interior stands, the conservation of these threatened elements requires urgent conservation measures because well preserved and unmanaged forests in the Mediterranean region are very rare.

Contrasting functional traits maintain lichen epiphyte diversity in response to climate and autogenic succession

AbstractAim Lichen epiphytes are important for biodiversity conservation and are also widely applied as environmental indicators. However, biogeographical and ecological knowledge underpinning lichen epiphyte conservation, and the use of lichens as indicators, is based primarily on a limited range of ‘macrolichen’ species. Wider trends in epiphyte biodiversity remain largely unexplored. This paper examines the community structure of lichen epiphytes on aspen (Populus tremula L.) in Scotland, including species across all functional groups and comprising, therefore, taxonomically difficult ‘microlichens’.Location Northern Britain (Scotland).Methods Epiphytes were sampled from 12 sites throughout Scotland and examined at two scales: between and within aspen stands. Species were classified into contrasting functional groups and ordination by detrended correspondence analysis was used to summarize community structure.Results Within aspen stands (between trees) epiphyte communities showed successional patterns related to tree age. These successional patterns changed predictably for stands aligned along a climatic gradient (between stands).Main conclusions A dual climatic–successional trend in epiphyte community structure is presented. Large‐scale trends in epiphyte diversity are explained as the local response of species with contrasting functional traits to climate and autogenic succession. Turnover of functional groups between stands is positively related to β‐diversity, and ecological limits to the frequency of contrasting functional groups are presented. Accordingly, the study and application of lichen species with similar functional traits may inadequately represent patterns of biodiversity. This prompts criticism of the currently accepted conservation strategy, i.e. (1) an emphasis in the conservation literature on ‘macrolichen’ species with similar ecologies and (2) the application of lichen indices over climatically variable geographical areas.

Effect of Plant Architecture on the Structure of Epiphytic Macroinvertebrate Communities in a Chinese Lake

ABSTRACT We examined the effect of different plant architecture types on epiphytic macroinvertebrates of a shallow macrophyte-dominated lake in China. Macroinvertebrates were sampled from four dominant submersed macrophytes in the lake—two dissected plants (Myriophyllum spicatum L. and Ceratophyllum demersum L.) and two undissected plants (Potamogeton maackianus A. Benn. and Vallisneria spiralis L.). Macroinvertebrate richness showed significant differences among four submersed macrophyte habitats, and higher density per g of dry plant were associated with dissected plants than undissected plants. The average abundance in dissected plants was as three-six times as in undissected plants. The biodiversity of epiphytic macroinvertebrates was higher in dissected plants than undissected plants. Our results suggest that dissected plants provide different habitat for macroinvertebrates than dissected plant, and this concurs with the hypothesis that the former could support more epiphytic macroinvertebrates than the latter.

AIR-QUALITY BIOINDICATION IN THE GREATER CENTRAL VALLEY OF CALIFORNIA, WITH EPIPHYTIC MACROLICHEN COMMUNITIES

Air-quality monitoring in the United States is typically focused on urban areas even though the detrimental effects of pollution often extend into surrounding ecosystems. The purpose of this study was to construct a model, based upon epiphytic macrolichen community data, to indicate air-quality and climate in forested areas throughout the greater Central Valley of California (USA). The structure of epiphytic lichen communities is widely recognized as an effective biological indicator of air-quality as sensitivities to common anthropogenic pollutants vary by species. We used nonmetric multidimensional-scaling ordination to analyze lichen community data from 98 plots. To calibrate the model, a subset of plots was co-located with air-quality monitors that measured ambient levels of ozone, sulfur dioxide, and nitrogen dioxide. Two estimates of ammonia deposition, which is not regularly monitored by any state or federal agency in California, were approximated for all plots using land-use maps and emissions est...

Does the process of drying submerged macrophytes affect community structure and composition of epiphytic diatoms?

This study investigates whether the process of pressing and drying a macrophyte host affects community structure and composition of epiphytic diatom communities. Epiphytic diatoms on submerged macrophytes from carbonate rivers and streams in southern Bavaria, Germany were sampled in order to study community structure and composition. Simultaneously, a specimen of the submerged macrophyte was taken to create a collection of dried plants. After 6 months of preservation, diatom samples were taken from the herbarium macrophytes. Detrended correspondence analysis, diversity and evenness results indicate that recent and dried communities are indistinguishable. These results suggest that epiphytic diatom communities sampled from historic herbarium macrophytes can be utilised as bioindicators to assess former water quality.

Composição florística e estrutura comunitária de epífitos vasculares em uma floresta de galeria na Depressão Central do Rio Grande do Sul

Apesar das florestas de galeria serem amplamente difundidas nos neotropicos, existem poucas informacoes disponiveis sobre seu epifitismo vascular. O objetivo deste estudo foi investigar a composicao floristica e a estrutura comunitaria dos epifitos vasculares em uma floresta de galeria que acompanha dois arroios na Depressao Central do Rio Grande do Sul, sul do Brasil. A area estudada situa-se na Estacao Experimental Agronomica (30°04' - 30°07' S e 51°40' - 51°42' W) da Universidade Federal do Rio Grande do Sul (UFRGS) a uma altitude aproximada de 40 m. O clima regional e subtropical umido (Cfa), com medias anuais de temperatura e precipitacao de 19,2 oC e 1.310 mm, respectivamente. Sessenta forofitos com DAP minimo de 10 cm foram amostrados atraves do metodo de pontos quadrantes. Os parâmetros de frequencia e diversidade foram estimados com base na ocorrencia epifitica sobre individuos forofiticos e sobre os segmentos fuste e copa. O levantamento floristico resultou em 13 familias, 32 generos e 50 especies. As familias mais ricas em especies foram Orchidaceae (13), Bromeliaceae (8), Polypodiaceae (8), Cactaceae (5) e Piperaceae (5). Duas pteridofitas, Microgramma vacciniifolia e Polypodium pleopeltifolium, apresentaram os maiores valores de importância. O indice de diversidade de Shannon foi 3,434 (nats) para toda a comunidade epifitica. Considerando os ambientes de fuste e copa, os valores foram 3,092 e 3,298, respectivamente. Estes valores intermediarios em relacao a outros estudos no sul do Brasil provavelmente refletem uma tipica situacao subtropical, onde a diversidade epifitica decresce com a diminuicao da temperatura e precipitacao.