Icelandic solfataras

Fumaroles and solfataras of Iceland, surrounded by very sparse communities on warm, acid and clayey soils under a humid, warm microclimate, comprising Cyanophycea carpets in the immediate vicinity of the vent, hepatica belts farther out, first of the small [Riccia bifurca] and [Fossombronia dumortieri], then of the more robust [Preissia quadrata], finally, vascular plant assemblies in which [Ophioglossum azoricum], [Sagina procumbens], [Plantago major var. pygmaea] are prominent. Vast expanses of sulphur-poisoned ground in the general vicinity of the solfataras are almost devoid of vegetation, with a few vascular plants in less poisoned areas, in particular, [Achillea millefolium].