Multiple lichen species growing on a fallen branch in unpolluted air. Lichens are formed from the a symbiotic association between a fungus and an alga

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Multiple lichen species growing on a fallen branch in unpolluted air. Lichens are formed from the a symbiotic association between a fungus and an alga. The alga is contained within the hyphae (filaments) of the fungus. Lichens are slow-growing, and are usually found on stones and the bark of trees. They are sensitive to pollution, and are a good indicator of air quality. Shrubby (fruticose) and leafy (foliose) lichens, seen here, tend to be more sensitive to atmospheric pollution than crustose species. Photographed in Snowdonia, North Wales, UK.

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Size: 4906px × 3562px
Photo credit: © CORDELIA MOLLOY/SCIENCE PHOTO LIBRARY / Alamy / Afripics
License: Licensed
Model Released: No

Keywords: -, air, atmospheric, bark, biodiversity, bioindicator, botanical, botany, branch, britain, british, clean, crustose, dioxide, ecological, ecology, environment, environmental, europe, european, flora, flower, foliose, fruticose, kingdom, lichen, lichens, mutualism, nature, plant, pollution, pure, purity, quality, rural, snowdonia, sulphur, symbiont, symbiosis, symbiotic, tree, uk, united, unpolluted, wales, welsh, wood