Lichens of the negev desert (Israel): Diversity, distribution, and relationship with microclimate

Lichens are among the most amazing organisms on our planet. Their very structure is unique: a symbiosis of two organisms-a fungus and algae (or cyanobacteria)-and so perfect that they behave and look like an absolute new being. Lichens occur on different substrates almost everywhere. They play a significant role in desert ecosystems where conditions are too harsh and limited for the life of most other organisms. The Negev desert occupying a significant part of the territory of Israel always was of great interest for lichenological investigations. At present, the lichen biota of the Negev desert includes 81 species of which the most common are saxicolous lichens. The studies of lichen ecology and physiology in the Negev desert showed that the main factor which influences lichen growth and activity in different habitats was water availability.