Andean aquatic vegetation in central Bolivia
Molina, José Antonio; Navarro, Gonzalo; De la Barra, Nelly; Lumbreras, Ana
This work focuses on the floristic and ecological study of aquatic Andean vegetation in central Bolivia at different levels. The local level was studied by means of the plant-community distribution and composition in a typical Andean hydrosere. This showed that water-plant communities including isoetid vegetation, helophytic vegetation and low amphibious vegetation could be distinguished within the aquatic environment. The next step involved collecting all the phytosociological information from central Bolivia, in addition to our own phytosociological relevés, to make numerical analyses. At a regional level, hierarchical classification showed floristic variability in two main groups: one with aquatic and amphibious vegetation characterized by Isoetes aff. lechleri, Ranunculus flagelliformis or Callitriche heteropoda, among others; and another with aquatic, amphibious, and also helophytic vegetation characterized by Zannichellia andina, Potamogeton striatus or Scirpus tatora, among others. The phytogeography of the characteristic plants indicates that the first group is mainly composed of relevés from orotropical locations of the Eastern Ranges, whereas the second for the most part comprises oro- to mesotropical locations in the western Andean ranges, Altiplano, Vacas Basin (eastern ranges) and dry inter-Andean valleys. The relationships between the distribution of water plants and the physical-chemistry of the water were carried out by CCA, and showed that the first group occurs in non-mineralized waters while the second group occurs in mineralized waters. All of this leads to the description of 14 plant communities from a floristic and ecological viewpoint.