Geography
Mainalo's ground is primarily made of lime, among various calcareous substrates.
Ecology
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The mountain houses many forests of Greek fir and Crimean pine. Natura 2000 cites these forests as the "[Greek fir and Crimean pine's] best representation in Peloponnisos."<sup>:59</sup>
- Endemic oro-Mediterranean heaths with gorse, covering of the mountain, this environment consists of a dry mountainous environment. Mediterranean heaths are usually dominated by Genista, while containing various other, often spined, shrubs like Acantholimon, Astragalus, Erinacea, Bupleurum, Ptilotrichum, Echinospartum, and Anthyllis. This environment also includes a variety of Asteraceae and Lamiaceae.