Epiphytes

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10–15, whereas higher abundances of zooplan...

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10–15, whereas higher abundances of zooplan...

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10-15, whereas higher abundances of zooplan...

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10–15, whereas higher abundances of zooplan...

During the past two decades we have gained much insight into the factors that regulate the productivity of seagrass dominated ecosystems, especially those at low latitudes. Here, we review and reassess the importance of plant-herbivore interactions in seagrass meadows, focusing on recent studies that have examined: 1) grazing on live seagrass leaves; 2) consumption of epiphytic algae growing on seagrass leaves; and 3) consumption of planktonic algae from the waters surrounding seagrass meadows. The major conclusion is that, in contrast to what has been reported in much of the literature on food webs in seagrass meadows, a diverse grazing pathway continues to represent an important conduit for the transfer of energy from the primary producers to higher order consumers. This remains true, although in many areas consumption of seagrasses is reduced in an historical context, owing to the overharvesting of many large species of herbivorous waterfowl, turtles and mammals.

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10–15, whereas higher abundances of zooplan...

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10–15, whereas higher abundances of zooplan...

The sampling of epiphytes is fraught with methodological difficulties. We present a protocol to sample and analyse vascular epiphyte richness and abundance in forests of different structure (SVERA). Epiphyte abundance is estimated as biomass by recording the number of plant components in a range of size cohorts. Epiphyte species biomass is estimated on 35 sample-trees, evenly distributed over six trunk diameter-size cohorts (10 trees with dbh > 30 cm). Tree height, dbh and number of forks (diameter > 5 cm) yield a dimensionless estimate of the size of the tree. Epiphyte dry weight and species richness between forests is compared with ANCOVA that controls for tree size. S Chao1 is used as an estimate of the total number of species at the sites. The relative dependence of the distribution of the epiphyte communities on environmental and spatial variables may be assessed using multivariate analysis and Mantel test. In a case study, we compared epiphyte vegetation of six Mexican oak forests and one Colombian oak forest at similar elevation. We found a strongly significant positive correlation between tree size and epiphyte richness or biomass at all sites. In forests with a higher diversity of host trees, more trees must be sampled. Epiphyte biomass at the Colombian site was lower than in any of the Mexican sites; without correction for tree size no significant differences in terms of epiphyte biomass could be detected. The occurrence of spatial dependence, at both the landscape level and at the tree level, shows that the inclusion of spatial descriptors in SVERA is justified.

Cocoa is produced in a wide range of land use systems, with the traditional shaded systems in Bahia (Brazil) as the most forest-like and biodiverse. The aim of this study was to evaluate the role of different cocoa agroforestry systems (AFSs) in maintaining community structure and interactions between ants and epiphytic bromeliads. The study was conducted at four sites in the cocoa producing region of the southeastern of the state of Bahia, Brazil, and comprised a native forest and three different cocoa AFSs. We found a total of 103 ant species associated with epiphytic bromeliads, with 83% of the species occurring in native forest canopy bromeliads also occurring in cocoa AFSs. The Cocoa Cabruca System (CAB) and the Rustic-Planted Shade System (RPS) had ant community structural components of biodiversity similar to those found in the native forest environment. The alpha and gamma diversity of ants found in Monospecific-Shaded Cocoa Agroforestry System (MCA) associated with Erythrina spp. shade trees were significantly different from the diversity found in the other AFSs and native forest. The presence of epiphytic bromeliads, regardless of the system and scale, maintained ant diversity in agroforestry system canopies similar to that of native forest. Using metrics derived from graph theory, we found a high level of specialization regarding ant–bromeliad interactions in native forest, with a gradual decrease in specialization with environmental homogenization. Agroforestry systems thus represent an important strategy for maintaining the structure of canopy-associated ant communities by enabling the establishment of numerous bromeliad species, thus contributing to the maintenance of ant diversity and services in a mosaic landscape AFSs and native forest.

This study focused on the monitoring and assessment of aquatic ecosystem functioning based on the abiotic and biotic features of Lake Nasser in the post-flood and pre-flood periods as the last ones before water storing behind the Grand Ethiopian Renaissance Dam. The physicochemical parameters, distribution and structure of biotic communities, including bacteria, phytoplankton, zooplankton, macrophytes, epiphytes and fish were analyzed at 15 sites. The values of most parameters (primarily temperature, total suspended solids, pH, orthophosphates, carbonates, sulphates and some cations) were higher in the pre-flood period, whereas higher values of conductivity, total dissolved solids, total solids, nitrites, nitrates, chemical oxygen demand, bicarbonates and chlorophyll a were recorded in the post-flood period. Cyanobacteria-dominated phytoplankton and total coliform bacteria were more abundant in the pre-flood period, and especially at sites 10-15, whereas higher abundances of zooplan...

ECOFISIOLOGÍA l metabolismo ácido de las crasuláceas (CAM, siglas del nombre en inglés) es un ejemplo de adaptación al estrés ambiental y se presenta en plantas de sitios con periodos de escasa disponibilidad de agua o de CO2. Este tipo de fotosíntesis es uno de los tres encontrados en los tejidos de las plantas vasculares para la asimilación de CO2 de la atmósfera (Taiz y Zeiger, 2002; Larcher, 2003). La fotosíntesis C3 (ciclo C3 o de Calvin-Benson) se realiza en los cloroplastos de todas las plantas con el uso de la enzima ribulosa 1, 5difosfato carboxilasa (rubisco) como catalizador de la reac

Epiphytic diatom communities on macroalgae from Iceland coastal waters were investigated during July 2005. Ten species of seaweeds have been collected belonging to brown, red and green algae. The analysis of epiphytic diatom community was carried out under scanning electron microscopy. The epiphytic diatom abundances varied from 7 ± 5 to 7524 ± 3491 cells mm−2. Erect growth forms were the most abundant, representing

Vegetative growth, reproductive effort, seedling establishment, and mortality of the bark epiphyte, Dimerandra emarginata (Orchidaceae), were studied over a 3-y period in the moist lowland tropical forest on Barro Colorado Island, Panama. The study included more than 350 individuals growing on 12 branches of five different host tree species. Mortality was highest among small individuals. Most deaths occurred during the dry season and were probably related to drought. Mortality among older individuals, on the other hand, was always related to the instability of the substrate, i.e. flaking bark, breaking branches or falling trees. Vegetative growth was slow. The average increase in size (= height of the most recent, fully developed shoot) was 2.7 cm over 3 y (not considering 'stemless' seedlings). This increase was negatively correlated with initial plant size. Growth was highly seasonal, with little variation between years. The reproductive effort increased strongly with plant size. Larger individuals produced fruits more frequently, in larger numbers and of larger size. After reproduction, plants showed reduced vegetative growth in the following year (in 1994). There was no negative effect on future reproduction. Compared to seed production, annual recruitment was very low and showed large year-to-year variation. Fewer than 50% of the seedlings survived the first dry season after germination. After 3 y, their average size was 0.5 cm. The results suggest that slow-growing epiphytes such as D. emarginata can attain considerable age and that their longevity -after an initial vulnerable juvenile stage -is almost exclusively limited by substrate durability.

Phyllospheric bacterial population from medicinal plants viz. Withania somnifera, Lantana camara, Solanum nigrum and Ocimum basilicum was examined. Endo and epiphytic bacteria were isolated on Luria Bertani (L.B.) agar medium from healthy tissues of medicinal plants. Different epiphytic and endophytic bacterial species showed different colonization frequencies. In epiphytic bacterial species, Ensifer ahhaerens had the maximum colonization frequency (67%), followed by Azotobacter chroococcum (54%), Micrococcus lylae (47%) and Kurthia zopfii (31%). While in case of endophytic study, Agromonas oligotrophica (100%), Xanthobacter flavus (75%), Lampropedia hyalina (46%), Microbacterium lacticum (40%), Kurthia zopfii (40%) and Phenylobacterium immobile (31%) showed maximum frequency. Furthermore, the antimicrobial activity of endophytes and their diversity in medicinal plants is concisely deliberated. Eight species of endophytic bacteria were found to produce antagonistic activity against pathogenic fungi and bacteria by plate assays. Results showed that endophytic bacterial isolates was antagonistic to fungi by agar diffusion method and bacteria by well diffusion technique. In vitro, the antimicrobial role gave fruitful results to open the way for complementary study in order to identify and purify the active compounds. In conclusion, endophytic bacteria from the four medicinal plants have antagonistic potential.

Cyrtopodium punctatum Lindley is an endangered epiphytic orchid restricted in the United States to southern Florida. Due to its ornamental value, the species was extensively collected from the wild during the past 100 years. Today, only a few plants remain in protected areas. As part of a conservation plan for the species, procedures for asymbiotic seed germination were developed. Five asymbiotic orchid seed germination media (PhytoTechnology Orchid Seed Sowing Medium, Knudson C, Malmgren Modified Terrestrial Orchid Medium, Vacin & Went Modified Orchid Medium, and -strengh Murashige & Skoog) were examined for their effectiveness in promoting seed germination and protocorm development under a 16/8 h L/D photoperiod and dark (0/24 h L/D). The influence of photoperiod on growth and development was also examined. Seeds were germinated under a 16/8 h, 12/12 h, 8/16 h L/D photoperiod, at 25 ± 3°C and allowed to develop in vitro for 10 weeks. After 10 weeks, developing seedlings were transferred to Sigma Phytatrays and returned to their assigned photoperiod treatments for continued seedling development for an additional 15 weeks. Highest germination occurred in 0/24 h L/D on PhytoTechnology Orchid Seed Sowing Medium and seedlings displayed more advanced development when cultured under 16/8 h L/D photoperiod after 15 weeks in Phytatrays. Thirty-five week old seedlings potted in coconut husk growing medium exhibited 90% survival following 5 weeks acclimatization to greenhouse conditions. This asymbiotic seed germination protocol for C. punctatum will facilitate future reintroduction projects involving this endangered species.

Episodes of symbiont-bleaching have been documented in field studies of epiphytic populations of the dinoflagellate-bearing foraminiferan Sorites dominicensis from Jupiter Sound in the Indian River Lagoon, Florida, and Carrie Bow Cay and Twin Cays, Belize. In August 2003, 13–16% of the population in Jupiter Sound exhibited evidence of bleaching, with cytoplasm that was either mottled or totally white. In July 2005, 18% of the population on the reef flat off Carrie Bow Cay, and 4% of the population in the tannin-stained waters of Boston Bay, Twin Cays, exhibited signs of bleaching. Symbiont bleaching in soritid foraminiferans may be a more widespread and recurrent phenomenon than has previously been recognized. Bleaching appears to be triggered by a combination of environmental factors that are similar to the conditions that trigger bleaching in corals, such as: subaerial exposure during extreme low spring tides in the summer months, high water temperatures, increased irradiance, exp...

Controversial data on the pathways and effects of lichen growth on and near bryophytes and vascular plants are reviewed. In most cases, plants which are used as growth substrates positively influence lichen mineral nutrition and are poorly affected by lichen overgrowth, but several reports of negative relationships, including lichen parasitism and allelopathic interferences, prevent generalizations. The allelopathy of terricolous lichens against neighboring plants has been suggested by in vitro investigations, and a multidirectional phytotoxic mode of action has been shown for lichen secondary metabolites. Recent researches on field settings, instead, offer little support of lichen allelopathy, and plant allelopathy against lichens has so far been neglected. A comparison with lichen-rock interactions indicates that a common set of physical and chemical factors can explain the heterogeneous reciprocal effects that exist between lichens and plants, which depend on the species involved, and highlights gaps that need further studies.

Seagrass epiphytes play an important role in seagrass habitats; however, available information from Central America is scarce. The present study focuses on macroalgal epiphytes on leaves of the seagrass Thalassia testudinum in the seagrass meadows at Punta Cahuita, Caribbean coast of Costa Rica, and it is the first one of its kind in Costa Rica. A representative amount for each algal epiphyte species found was collected, preserved and identified to the lowest possible taxon. Preserved samples of each species were deposited in the Herbarium of the Universidad de Costa Rica. A total of 26 species of macroalgae were found: 15 species belonging to Rhodophyta, four to Chlorophyta, six to the class Phaeophyceae, and one diatom species which could not be identified. The present inventory reports three species that are new for the phycological flora of Costa Rica, four species are reported for the first time for the Caribbean coast of Costa Rica, and 17 are new reports for the Parque Nacional Cahuita area. Epiphyte species number might further rise if sampling efforts and the study area increased. Rev. Biol. Trop. 56 (Suppl. 4): 163-174. Epub 2008 December 12.

Water-impounding foliage (l tank) characterizes many bromeliad species but, to date, a quantitative evaluation of the effectiveness of these structures to bridge rainless periods is not available. We present a model that analyses the capacity of these phytotelmata to supply moisture to the bromeliad as a function of plant size, and parameterize it for two epiphyte species, Tillandsia fasciculata and Guzmania monostachya. All parameters related to the recharging of a tank (e.g. catchment area, or tank capacity) and those related to water loss from the tank (e.g. tank water surface, or water absorption from the tank by the plant) changed with plant size. For both species a similar qualitative sizerelated pattern emerged : smaller individuals dried out much faster than larger conspecifics. Modelling the changes in tank water content for an entire year revealed that in the seasonal climate of Barro Colorado Island, Panama, tanks of smaller plants (1 g d. wt) are expected to lack water for up to 110 d (in T. fasciculata). Regardless of plant size, individuals of G. monostachya were consistently more efficient than T. fasciculata in maintaining moisture in their tanks. Our results provide insight into the limitations of water-impounding tanks as an adaptation to cope with an intermittent water supply typical for epiphytic habitats. These limitations are particularly pronounced for smaller individuals.

Vertical stratification and host preference by vascular epiphytes in a Chiapas, Mexico, cloud forest. The high diversity of vascular epiphytes in neotropical montane forest has been explained as the result of vertical stratification of the forest and specific relationships between epiphytes and their hosts trees at local scales. In a lower montane cloud forest, we studied the vertical stratification and host preferences of vascular epiphytes in a 0.0625 ha plot where 41 trees ≥ of 10 cm DBH were sampled during 12 months in 2001 and 2002. We found 43 epiphyte species growing on 15 tree genera. We tested for vertical strata and host preferences using 19 epiphyte taxa. We found strong evidence that epiphytes divided the canopy, but those epiphyte species dispersed by animals were generalists with respect to hosts and vertical strata. Wind dispersed epiphytes were vertically stratified, with a higher richness in the lowest tree strata. On average the epiphytes preferred 3.5 host species, suggesting low host preference. Two host species, Ardisia and Quercus, were avoided by the majority of the epiphyte species. Our results show that epiphytes divided the canopy horizontally and were stratified vertically, suggesting that host identity could be important determining the abundance of colonizing sites for epiphytes. Rev. Biol. Trop. 56 (4): 2069-2086. Epub 2008 December 12.

Fossil leaves of two Early Miocene orchids ( Dendrobium and Earina ) are reported from New Zealand. The distinctive, raised tetra-to cyclocytic stomatal subsidiary cells of Earina and characteristic papilla-like absorbing glands and " ringed " guard cells of Dendrobium support the placement of the fossils into these genera. These therefore represent the fi rst Orchidaceae macrofossils with cuticular preservation, the oldest records for subfamily Epidendroideae, as well as the fi rst New Zealand and southern hemisphere fossil records for Orchidaceae. These taxa belong in basal clades to the Vandeae/Cymbideae or Epidendreae ( Earina ) and the Australasian clade of Dendrobium sensu lato. This phylogenetic placement demonstrates expansion of epiphytic orchids into Zealandia by the mid-Cenozoic and an important role for southern continents in the diversifi cation of Orchidaceae.

Abstract. Plant life-form abundance along a 600 m altitudinal gradient (1600–2200 m a.s.l.) in the semi-arid valley of Zapotitlán, México was correlated with soil characteristics and climatic variables. One mixed soil sample was taken and analysed for each of six elevations, temperature was estimated using a terrestrial thermal gradient, and precipitation using a linear regression between total annual precipitation and the elevation of the weather stations in the valley. Rosettes, microphanerophytes, therophytes and nanophanerophytes were well represented throughout the gradient. Columnar cacti were restricted to the 1600–1800 m range, and geophytes to the 1700–1800 m range. In general, abundance of life forms was inversely associated with altitude. Multiple regression analysis did not show parameters to significantly explain the abundance of rosettes, nanophanerophytes, epiphytes, geophytes and hemiparasites; altitude and nitrogen proved significant for columnar cacti, succulents and chamaephytes; altitude, pH, electrical conductivity and nitrogen were significant for globose cacti; pH was significant for therophytes; and altitude was significant for microphanerophytes.

New specimens of Botryopteris Renault deriving from the Permian of the Maranhão Basin (NE Brazil) are both the first evidence of this palaeozoic fern group from the Southern Hemisphere and the youngest known to date. These remains cannot be assigned to any known species of the Botryopteridaceae. Therefore, the new species Botryopteris nollii sp. nov. is established. One of the most conspicuous characters of this new fern is the ability to grow in different forms. Firstly, it has been found rooted within the marginal trunk base of the tree ferns Grammatopteris freitasii Rößler and Galtier and Psaronius brasiliensis Brongniart. Secondly, cauline organs, foliar members and adventitious roots of this fern formed a compound system of a so-called false trunk. This results from the formation of closely spaced spirally arranged foliar members of different order on upright stems and of the repetitive development of shoots from foliar-borne buds inside the trunk. The newly collected material is preserved as silicified permineralisation, and therefore allows to recognise characters of vegetative morphology but also details of the anatomy and internal organisation. Botryopteris nollii sp. nov. is characterised by nearly circular protostelic stems and stipes/rachises that show a dorsiventral ω-shaped vasculature. The new fern underlines the striking growth form diversity seen in the whole family Botryopteridaceae.

In dry Mediterranean environments, the epiphytic habitats are generally poor in bryophytes. However, Sierra Alhamilla, a mountain embedded in one of the driest areas in Europe, is an exception. It shelters an evergreen oak wood, whose richness in epiphyte bryophytes is similar to or higher than that of humid mountain ranges from the Iberian Peninsula and North Africa. The genus Orthotrichum , besides dominating the epiphyte communities on tree trunks and bases, is the most diverse group (45% of the catalogue), and comprises a bulk of species (e.g., Orthotrichum scanicum , Orthotrichum ibericum , Orthotrichum speciosum var. brevisetum ) that makes this site especially original. The profiles of the recorded bryoflora (dominance of Orthotrichaceae and Pottiaceae, prevalence of cushions and short turfs and high similarity of tree base and trunk bryophyte communities) indicate an epiphytic bryoflora mainly conditioned by the dry climate. However, the species richness and the biogeographical profile (e.g., dominance of temperate element and occurrence of species that have mesic affinities), together with the altitude influence on structure and composition of bryophyte communities, suggest the existence of microclimatic factors that soften the environmental aridity. This softening effect could be more important at higher altitudes, which are floristically richer than the lower ones.

Foram realizados estudos na região entremarés de recifes da Praia de Boa Viagem, Recife, nordeste do Brasil, em dezembro de 2009 (período seco) e abril de 2010 (período chuvoso), para analisar a estrutura da comunidade das macroalgas epífitas em outras macroalgas. O material foi coletado em dois trechos recifais, cada um com aproximadamente 30 m de extensão, em diferentes compartimentos favoráveis ao crescimento de macroalgas. Todo o material coletado permaneceu congelado até o procedimento de análise. Os exemplares estão depositados no Herbário do Instituto de Botânica, São Paulo, Brasil (SP). Foram encontradas nove novas ocorrências para a costa pernambucana: Boodlea composita (Harv.) F. Brand, Ceramium corniculatum Mont., Chaetomorpha clavata Kütz., C. nodosa Kütz., Chondracanthus cf. saundersii C.W. Schneid. & C.E. Lane, Cladophora laetevirens (Dillwyn) Kütz., Neosiphonia sphaerocarpa (Børgesen) M.-S. Kim & I.K. Lee, Ulva linza L. e U. prolifera O.F. Müll. Destas, quatro tiveram...

Vegetative growth of the xerophytic epiphyte Tillandsia flexuosa was studied both in situ and under controlled conditions in a growth chamber. Realized growth rates under natural conditions in the dry Peninsula de Azuero (Panama) were similar to those of previously studied epiphytes from wetter habitats. Near-optimal ex situ conditions stimulated growth only in smaller individuals. Field-collected plants were initially not nutrient starved, which can be deduced from the lack of a growth response to fertilization in contrast to a substantial irrigation effect. After several months, both increased water and nutrient availability had a strong effect on growth. A likely explanation for this finding is luxury consumption of nutrients.

Marine macroalgae harbour abundant and diverse assemblages of epifauna. Patterns of distribution and abundance of epifauna, which are often variable in space and time, differ markedly among macroalgae species. Nonindigenous seaweeds may alter composition and structure of epifaunal assemblages and therefore harbour different assemblages from those associated with native macroalgae. In this study, we analysed the epifaunal assemblages associated with the native algae Bifurcaria bifurcata and the invasive alga Sargassum muticum on the southern part of the Galician coast (north-west Spain). In particular, we tested the hypothesis that there were differences in the epifaunal assemblages associated with the native and invasive algae. We used a hierarchical spatial sampling design to identify if these differences were consistent over space and time. Results indicated that there were significant differences between epifaunal assemblages associated with both algae. The fact that such differences were, in general, consistent at different spatial scales suggests that biological factors related to the specific habitat might play a more important role than physical factors as determinants of epifaunal distribution. This study also showed that S. muticum seems to supply a new and additional habitat for the native epifauna, contributing to increases in the spatial and temporal variability of epifaunal assemblages.

In vitro cultivation of three Kappaphycus alvarezii (Rhodophyta, Areschougiaceae) variants (green, red and brown) exposed to a commercial extract of the brown alga Ascophyllum nodosum (Fucaceae, Ochrophyta) Abstract Diseases such as "ice-ice" and "goose bumps" are responsible for loss of almost 70% of infected Kappaphycus production. To improve the growth of K. alvarezii and reduce the impact of diseases, the effect of the commercial Ascophyllum nodosum extract was tested. Five grams of apical branches of each K. alvarezii variant (n=6) were bathed at different extract concentrations (e.g., 5, 10, 15, 20, 25, and 30 g L −1 ) for 1 hour. To test the effect of the extract on epiphytes apical tips were not cleaned. After 2 weeks, the epiphytes such as Cladophora sp. and Ulva sp. disappeared. Polysiphonia subtilissima survived but its appearance was weak. The highest K. alvarezii growth rates were observed at extract concentrations of 15 and 20 g L −1 (p<0.001), almost double the expected for a 45day production cycle used at Sepetiba Bay, Brazil. These results show that the extract was efficient at improving the growth of K. alvarezii and reducing the presence of some epiphytes.

Vriesea maculosa Mez is a poorly known species with no further recordings since the type collection 101 years ago. As a result of our research about Vriesea as part of the study of the Flora of Bahia, Brazil, new specimens and data are now available for this species justifying an amendment to its description. We provide a complete taxonomical description, including floral details analyzed in freshly collected material. We propose to treat V. fabioi as a new synonym of V. maculosa, and expand on the distribution and phenotypic variation found between populations. The species is illustrated in detail, using line drawings as well as photographs of different populations in the field.

In dry Mediterranean environments, the epiphytic habitats are generally poor in bryophytes. However, Sierra Alhamilla, a mountain embedded in one of the driest areas in Europe, is an exception. It shelters an evergreen oak wood, whose richness in epiphyte bryophytes is similar to or higher than that of humid mountain ranges from the Iberian Peninsula and North Africa. The genus Orthotrichum , besides dominating the epiphyte communities on tree trunks and bases, is the most diverse group (45% of the catalogue), and comprises a bulk of species (e.g., Orthotrichum scanicum , Orthotrichum ibericum , Orthotrichum speciosum var. brevisetum ) that makes this site especially original. The profiles of the recorded bryoflora (dominance of Orthotrichaceae and Pottiaceae, prevalence of cushions and short turfs and high similarity of tree base and trunk bryophyte communities) indicate an epiphytic bryoflora mainly conditioned by the dry climate. However, the species richness and the biogeographical profile (e.g., dominance of temperate element and occurrence of species that have mesic affinities), together with the altitude influence on structure and composition of bryophyte communities, suggest the existence of microclimatic factors that soften the environmental aridity. This softening effect could be more important at higher altitudes, which are floristically richer than the lower ones.

We examined the distribution and abundance of nonvascular epiphytes on western hemlock trees in an oldgrowth coniferous forest focusing on patterns of epiphyte distribution at different spatial scales, epiphyte abundance amongst trees differing in size, and crown structures associated with epiphyte abundance. Total epiphyte cover was greatest in four canopy microhabitats: the upper canopy strata, crowns of large trees, lower crown branches, and inner branch plots. Epiphyte functional groups were stratified vertically within the stand and horizontally within branches. Alectorioid and "other" lichens were most abundant in the upper canopy and outer branch plots. Cyanolichens and Sphaerophorus globosus (Huds.) Vain. were most abundant in the lower to mid canopy. Although cyanolichens were most abundant in middle branch plots, Sphaerophorus was most abundant in inner branch plots. Bryophytes were most abundant in the lower canopy and inner branch plots. At the stand level, canopy height and tree size were the main influences on epiphytes. Within trees, plots closer to the tree trunk and lower in the crown had the greatest abundance of epiphytes. In this forest, understory trees were colonized first by bryophytes, not by alectorioid and "other" lichens as is common for small trees in young stands.

Mexico possesses a great species diversity of Crassulacean Acid Metabolism (CAM) plants. These plants can grow in places where water is infrequent, such as arid and semi-arid zones, and tree canopies, or as aquatic plants in places with low CO2 availability. This review presents methodological, evolutionary, ecological, and physiological aspects on CAM plants. Also, it shows data from recent studies related to the environmental effect on changes in the photosynthesis CAM. Finally, we made a consideration about the lack of studies on the physiology of CAM plants in Mexico despite its enormous diversity.

Unique components of tropical habitats, such as abundant vascular epiphytes, influence the distribution of species and can contribute to the high diversity of many animal groups in the tropics. However, the role of such features in habitat selection and demography of individual species has not been established. Understanding the mechanisms of habitat selection requires both experimental manipulation of habitat structure and detailed estimation of the behavioral and demographic response of animals, e.g., changes in movement patterns and survival probabilities. Such studies have not been conducted in natural tropical forest, perhaps because of high habitat heterogeneity, high species diversity, and low abundances of potential target species. Agroforestry systems support a less diverse flora, with greater spatial homogeneity which, in turn, harbors lower overall species diversity with greater numerical dominance of common species, than natural forests. Furthermore, agroforestry systems are already extensively managed and lend themselves easily to larger scale habitat manipulations than protected natural forest. Thus, agroforestry systems provide a good model environment for beginning to understand processes underlying habitat selection in tropical forest animals. Here, we use multistate, capture-recapture models to investigate how the experimental removal of epiphytes affected monthly movement and survival probabilities of two resident bird species (Common Bush-Tanager [Chlorospingus ophthalmicus] and Golden-crowned Warbler [Basileuterus culicivorus]) in a Mexican shade coffee plantation. We established two paired plots of epiphyte removal and control. We found that Bush-Tanagers were at least five times more likely to emigrate from plots where epiphytes were removed compared to control plots. Habitat-specific movement patterns were not detected in the warbler. However, unlike the Golden-crowned Warbler, Common Bush-Tanagers depend upon epiphytes for nest sites and (seasonally) for foraging. These dispersal patterns imply that active habitat selection based on the presence or absence of epiphytes occurs in C. ophthalmicus on our study area. Survival rates did not vary with habitat in either species. Interestingly, in both species, survival was higher in the nonbreeding season, when birds were in mixed-species flocks. Movement by Common Bush-Tanagers into areas with epiphytes occurred mostly during the breeding season, when mortality-driven opportunity was greatest.

We studied the community and habitat occupation of epiphytes to understand how these plants cope with a supposedly stressful habitat: i) how general epiphytes occupy tree trunks, ii) how epiphytic bromeliads, occupy their supportive trees, iii) how CAM bromeliads are spatially distributed. The study was done in the dry forest of Jacarepiá, State of Rio de Janeiro. Data collection on epiphytes, phorophytes, and trees was based on the point-center quarter method. The photosynthetic pathway of the bromeliad species was determined using isotope ratio mass spectrometry. The presence of Gesneriaceae, Araceae, and Cactaceae indicates that some humidity is present in the area allowing the presence of supposedly less-specialized epiphytes. There was no correlation between epiphyte abundance and phorophyte diameter, and phorophytes had larger sizes than trees that do not host epiphytes. There was correlation between tree diameter and bromeliad abundance, and lack of correlation between diameter and bromeliad richness. Only one species was typical of the understorey and one was typical of the canopy, while intermediate heights were occupied by different species. The only C3 bromeliad species (Vriesea procera (Mart. ex Schult.f.) Wittm.) was significantly more exposed than the other species. If CAM occurrence is related to water economy, the fact that a C3 species is subjected to more exposed conditions is remarkable. Further comments are presented on the proportion between CAM bromeliad species and abundance in dry forest. Regarding life forms, holoepiphytes, as opposed to hemiepiphytes, showed not to be restricted by the phorophyte's diameter suggesting a more successful establishment of this life form.

Many epiphytes in Swedish beech forests are associated with old and damaged trees. In this study we examined the impact of bark, soil and stemflow pH, water-holding capacity and bark structures on this association. We also analyzed whether the influence of these factors differed between species of conservation concern (red-listed and indicator species of woodland key habitats) and species not of conservation concern. One hundred and one age-determined living beech trees (range 58-277 yrs) in 13 beech-dominated stands were surveyed in a forest landscape in southern Sweden. We recorded 119 species in total (76 lichens, 43 bryophytes) of which 21 were red-listed and 17 indicator species (26 lichens, 12 bryophytes). NMS ordination showed that the species composition of lichens changed primarily with tree age and along the gradient of smooth bark versus moss cover. Bark pH and tree vitality were the most important gradients for bryophyte composition. The combination of old damaged beech trees and high bark pH resulted in the highest mean number of species of conservation concern for both lichens and bryophytes. The link between these factors is partly explained by a positive effect of tree age on the stemflow pH. Species number of bryophytes not of conservation concern increased with bark pH, whereas the corresponding group of lichens was favored primarily by increased light availability. Neither the water-holding capacity of bark nor soil pH affected patterns of species number. The results from this study show that old beech trees infected by fungi, with a higher bark pH, are the most valuable trees for epiphytes of conservation concern.