Flora and water chemistry in a relictic mire complex:: the Sierra Segundera mire area (Zamora, NW Spain)

Chemical variables, algae, bryophytes, and vascular plants were determined in twelve mires located in the plateau of the Sierra Segundera range. All the mires studied are minetrophic in relation to water origin, and oligotrophic poor fens in relation to water chemistry. They were classified into two types: (a) 'slope mires', developed in effluent basins or depressions on slopes, usually small in size and poorly developed, and (b) 'basin mires', formed in closed basins, more developed than the previous type, always including hummocks and hollows, and in some cases sedge swamps in the ponds margins. The Sierra Segundera mire system is one of the better conserved mire complexes in the Iberian Peninsula. Bryophyte and vascular plant communities were similar to those in central and northern Europe, although some Mediterranean taxa tolerating water level variation also exist. Diatomaceae were scarce whilst Cyanophyta were relatively common, which differentiate those mires from northern European ones.