Search results
Results from the WOW.Com Content Network
Although some photosynthetic partners in a lichen can survive outside the lichen, the lichen symbiotic association extends the ecological range of both partners, whereby most descriptions of lichen associations describe them as symbiotic. Both partners gain water and mineral nutrients mainly from the atmosphere, through rain and dust.
The ability to fix nitrogen enables lichen to live in nutrient-poor environments. Lichen can also extract nitrogen from the rocks on which they grow. Nitrogen fixation, and hence the abundance of lichen and their host plants, may be decreased by application of nitrogen-based agricultural fertilizer and by atmospheric pollution.
Crust lichens include crustose and areolate lichens that are appressed to the soil substrate, squamulose lichens with scale- or plate-like bodies that are raised above the soils, and foliose lichens with more "leafy" structures that can be attached to the soil at only one portion. Lichens with algal symbionts can fix atmospheric carbon, while ...
This role is particularly important in mature and old-growth forests, where studies have shown that invertebrate abundance can be significantly higher on trees with abundant lichen growth compared to those without. [24] These lichens also form important associations with bryophytes (non-vascular land plants), particularly in humid forest ...
Crustose lichens on a wall Growth of crustose lichen on a tree trunk. Crustose lichens are lichens that form a crust which strongly adheres to the substrate (soil, rock, tree bark, etc.), making separation from the substrate impossible without destruction. [1] The basic structure of crustose lichens consists of a cortex layer, an algal layer ...
Overall, about 100 species are known to occur as autotrophs in lichens. All the algae and cyanobacteria are believed to be able to survive separately, as well as within the lichen; that is, at present no algae or cyanobacteria are known which can only survive naturally as part of a lichen. [7]
Lichens and nitrogen cycling – some lichens (in particular those with cyanobacteria as a photobiont) can fix nitrogen. [26] Lichen biogeography – the study of the current distribution of extant lichens and the reasons for those distributions. [30] Lichen resynthesis – lichens can be artificially "recreated" by combining partners in a lab ...
Lichens are known in which there is one fungus associated with two or even three algal species. Rarely, the reverse can occur, and two or more fungal species can interact to form the same lichen. [12] Both the lichen and the fungus partner bear the same scientific name, and the lichens are being integrated into the classification schemes for fungi.