Biodiversity Of Epiphytic Lichens Research Articles

Old trees as a key source of epiphytic lichen persistence and spatial distribution in mountain Norway spruce forests

Habitat loss and fragmentation can negatively impact the persistence of dispersal-limited lichen species with narrow niches. Rapid change in microclimate due to canopy dieback exposes species to additional stressors that may limit their capacity to survive and colonize. We studied the importance of old trees as micro-refuges and microclimate stability in maintaining lichen survival and diversity. The study was situated in mountain Norway spruce (Picea abies) forests of the Gorgany Mountains of the Ukrainian Carpathian mountain belt. Lichens were collected on 13 circular study plots (1000 m2). Dendrochronological methods were used to reconstruct age structure and maximum disturbance event history. A linear mixed effects model and general additive models were used to explain patterns and variability of lichens based on stand age and disturbance history for each plot. Tree age was the strongest variable influencing lichen diversity and composition. Recent ( 200 years old) that survived the disturbances served as microrefuges for the habitat-specialized and/or dispersal limited species, thus epiphytic lichen biodiversity was markedly higher on those plots in comparison to plots without any old trees. Most species were able to survive microclimatic change after disturbances, or recolonize disturbed patches from surrounding old-growth forests. We concluded that the survival of old trees after disturbances could maintain and/or recover large portions of epiphytic lichen biodiversity even in altered microclimates.

Integrated biomonitoring of air quality with plants and lichens: A case study on ambient ozone from central Italy

A biennial integrated survey, based on the use of vascular plants for the bioindication of the effects of tropospheric ozone together with the use of automatic analysers of ozone, as well as the mapping of lichen biodiversity was performed in the area of Castelfiorentino (Tuscany, central Italy). Photochemically produced ozone proved to be a fundamental presence during the warm season, with maximum hourly means reaching 114 ppb, exceeding the information threshold as fixed by EU: the use of supersensitive tobacco Bel-W3 confirmed the opportunity of carrying out detailed cost-effective monitoring surveys. The potential for didactical and educational implications of this methodology are appealing. Critical levels set up for the protection of vegetation have exceeded considerably. The comparison of biomass productivity in sensitive and resistant individuals (NC-S and NC-R white clover clones, in the framework of an European network) provided evidence that ambient ozone levels are associated with relevant reduction (up to 30%) in the performance of sensitive material; effects on flowering were also pronounced. The economic assessment of such an impact deserves attention. Mapping of epiphytic lichen biodiversity--which has been used to monitor air quality worldwide--was not related to ozone geographical distribution as depicted by tobacco response.

Diversity of Epiphytic Lichens and Hg Contents of Xanthoria parietina Thalli as Monitors of Geothermal Air Pollution in the Mt. Amiata Area (Central Italy)

The diversity of epiphytic lichens and mercury concentrations in lichen samples were measured to monitor the release of airborne pollutants from the industrial exploitation of geothermal resources in the Mt. Amiata area (Italy). The lichen biodiversity showed a general condition of moderate environmental alteration around the geothermal power plants, contrasting with the low environmental alteration of the remaining sites investigated. According to the accumulated Hg in lichen thalli, it was possible to estimate mean Hg and H2S concentrations in the air, which resulted in very good agreement with values measured instrumentally. Based on these data and the correlation between lichen diversity values and Hg concentrations in lichens, it was possible to calculate the threshold of 8 μg/m3 H2S as responsible for the worsening from low to moderate environmental alteration according to the biodiversity of epiphytic lichens, and to infer that around geothermal power plants, although not toxic to humans, H2S concentrations are such to alter the nasal quality of the air. Based on the growth rate of X. parietina, it was possible to convert Hg concentrations into estimates of average Hg deposition rates, which showed fluxes of the order of 65–100 mg/ha/y, indicating a dispersions factor of about 104 for the Hg emitted from the geothermal power plants.

Biodiversity of epiphytic lichens and heavy metal contents of Flavoparmelia caperata thalli as indicators of temporal variations of air pollution in the town of Montecatini Terme (central Italy)

The results of a biomonitoring survey carried out in the town of Montecatini Terme (central Italy) in the period 1993–2000 using the biodiversity of epiphytic lichens and the accumulation of heavy metals in thalli of Flavoparmelia caperata as indicators of air pollution are reported. From 1993 to 2000, the mean ILD value for the whole study area increased from 18±18 to 42±22, the lowest ILD value increased from 0 to 11 and the highest ILD value increased from 67 to 84. A ‘lichen desert’ was found only in 1993 and stations classified as ‘natural’ were lacking only in 1993 and 1996. Concentrations of all heavy metals decreased from 1993 to 1999. It is concluded that vehicular traffic is the main source of atmospheric pollution in the study area. The most likely changes that may have caused lichen communities to improve and heavy metals to drop is conversion of heating systems to methane (abatement of SO 2) and the use of unleaded gasoline (reduction of Pb). The present results showed that despite their slow growth rate, lichens respond rapidly to decreasing concentrations of air pollutants, allowing annual changes to be detected.

Plants as indicators of urban air pollution (ozone and trace elements) in Pisa, Italy.

A biennial integrated survey, based on the use of vascular plants for the bioindication of the effects of tropospheric ozone, was performed in the area of Pisa (Tuscany, Central Italy). It also investigated the distribution of selected trace elements in plants and the data were compared with those obtained from the use of passive samplers, automatic analysers of ozone and lichen biodiversity. Photochemically produced ozone proved to be present during the warm season, with maximum hourly means surpassing 100 ppb: the use of supersensitive tobacco Bel-W3 confirmed the value of detailed, cost-effective, monitoring surveys. Trials with clover clones demonstrate that sensitive plants undergo severe biomass reduction in the current ozone regime. The mean NC-S (clover clone sensitive to ozone):NC-R (resistant) biomass ratio ranged from 0.7 (in 1999) to 0.5 (in 2000). The economic impact of these reductions deserves attention. The data obtained using passive ozone samplers exceeded those obtained using an automatic analyser. The mapping of epiphytic lichen biodiversity was not related to the geographical ozone distribution as can be seen from the tobacco's response. Lettuce plants grown under standardized conditions were used positively as bioaccumulators of trace elements: Pb was abundantly recovered, but a large portion of this element was removed by washing.

Diversity of epiphytic lichens and metal contents of Parmelia caperata thalli as monitors of air pollution in the town of Pistoia (c Italy).

The results of a biomonitoring survey carried out in the town of Pistoia (central Italy) using the biodiversity of epiphytic lichens and the accumulation of heavy metals in thalli of Parmelia caperata as indicators of air pollution are reported. Compared to previous surveys, the overall situation generally improved, with higher lichen diversity at most stations and lower metal concentrations in P. caperata thalli. However, the general picture according to a calibrated sale of environmental naturality/alteration was substantially negative, with about 87% of the study area classified as 'altered' (including the lichen desert) or 'semi-altered'. To explain this apparent contradiction, it has been suggested that lichen colonization is determined by declining SO2 concentrations, while major injuries to lichen communities are caused by the constantly high levels of NOX. In spite of the low levels of Pb measured in P. caperata thalli, vehicular traffic was excluded as the main source of atmospheric pollution. Domestic heating seems to be the main case of changes in the diversity of epiphytic lichens in the study area.

Biodiversity of epiphytic lichens as indicator of air pollution in the geothermal area of Lardello (Tuscany, Central Italy)

The results of a biomonitoring survey carried out in the geothermal area of Larderello (Tuscany, central Italy) using the biodiversity of epiphytic lichens as an indicator of air pollution are reported. A desert was lacking, and stations classified as altered were found only in the surroundings of two old power plants that ceased production in 1992 and 1997, respectively, and installations for the extraction of boron salts. Areas of semi-alteration were found in surrounding areas of all other power plants. The overall pattern of increasing biodiversity with distance from geothermal power plants suggested that air pollution from geothermal installations, chiefly hydrogen sulfide, is the main cause of the observed impoverishment in lichen communities.

Temporal variation of air pollution in a geothermal area of central Italy: Assessment by the biodiversity of epiphytic lichens

The results of a biomonitoring survey carried out in the geothermal area of Travale-Radicondoli (central Italy) are reported. The aim of the study was to evaluate the temporal variation of air pollution from 1992 to the present, based on the actual biodiversity of the epiphytic lichens compared with that of a previous study in the same area. Although instrumental measurements were not available, it was assumed that variations in the biodiversity mostly reflected changes in the air pollution status. Furthermore, adopting a before-after strategy, the impact of a sansa oil extraction plant built in 1993 was also evaluated. The results showed that after 8 years, the geothermal area of Travale-Radicondoli is undergoing a gradual process of improvement, as clearly indicated by the colonization of some species in areas previously affected by the lichen desert;. The surroundings of the geothermal power plants did not show evident changes from the previous study, as the biodiversity values remain...

Biodiversity of epiphytic lichens as indicator of air pollution in the geothermal area of Lardello (Tuscany, Central Italy)

Biodiversity of epiphytic lichens as indicator of air pollution in the geothermal area of Lardello (Tuscany, Central Italy)

Temporal variation of air pollution in a geothermal area of central Italy: Assessment by the biodiversity of epiphytic lichens

Temporal variation of air pollution in a geothermal area of central Italy: Assessment by the biodiversity of epiphytic lichens

Biodiversity of epiphytic lichens and air pollution in the town of Siena (Central Italy)

The results of a biomonitoring survey carried out in the town of Siena (central Italy) using the biodiversity of epiphytic lichens as indicator of air pollution are reported. The general picture was rather good, with more than 60% of the study area being in the categories “semi-natural” or “natural” according to a calibrated scale of environmental naturality/alteration. Compared with the situation of 1995, ameliorating conditions were found as a result of an improvement in air quality over time.

Contribución al conocimiento de los líquenes epifíticos de la sierra de Alcaraz (Albacete, España)

A catalogue of epiphytic lichens from the Sierra de Alcaraz (Albacete) mountains is presented in this study. A total number of 131 species is reported. According to our data, 47 species are new records in Albacete Province and 15 in Castilla La Mancha territory. For each species ecological and chorological remarks are included. Acrocordia cavata, Bacidia bagliettoana, Chaenotheca chrysocephala, Ch. ferruginea, Ch. trichialis, Cyphelium inquinans, Imshaugia aleurites, Melanelia laciniatula, Melaspilea proximella, Micarea prasina, Mycobilimbia sabuletorum, Parmeliopsis ambigua, Pertusaria ophthalmiza and P. paramerae are specially considered due to its chorological implications in the Iberian Peninsula. We point out the localitiy “Sierra del Calar de la Osera” in Paterna del Madera because of the larger biodiversity of epiphytic lichens found.

Re-mapping epiphytic lichen biodiversity in The Netherlands: effects of decreasing SO2and increasing NH3

SUMMARY In a follow-up of De Wit's (1976) inventory of epiphytic lichens in The Netherlands, c. 17% of the area covered in that study was re-inventoried, using a comparable method. A strong increase in species diversity became apparent, probably caused by a decrease in SO2 concentration. In a comparison of various indicators for SO2 concentration derived from the epiphytic vegetation (number of species per sample point and number of species per 5 × 5 km2, or composite measures based on multivariate statistics), the number of species per 5 × 5 km2 grid square had the strongest correlation with the measured SO2 concentration. A second factor affecting epiphytic vegetation was the atmospheric NH3 concentration. High concentration of this compound caused a dominance of nitrophytic species. The rate of change in the epiphyte vegetation between 1988 and 1989 was consistent with the rate of decrease of the SO2 concentration during the preceding 5 years.