Phytocoenologia
37 (3Ð4)
753Ð768
BerlinÐStuttgart, December 21, 2007
Andean aquatic vegetation in central Bolivia by Jose´ Antonio Molina, Gonzalo Navarro, Nelly De la Barra and Ana Lumbreras, Madrid (Spain) and Cochabamba (Bolivia) with 3 figures and 2 tables Abstract. 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 releve´s, 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 releve´s 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. Keywords: bioindicators, CCA, central Andes, classification, phytosociology, water-plant community.
1.
Introduction
Wetlands include swamps, bogs, marshes, mires, lakes and floodplains, and cover an estimated total area of nearly three million square kilometers of the earth’s surface (Groombridge & Jenkins 1998, http://www.unep.org). They play an important role in ecology, as they are intermediate areas between water and land ecosystems and perform a range of important functions including the transfer and storage of water, bio-geochemical transformations, maintaining atmospheric carbon balance, primary productivity, decomposition, and sustaining community/habitat. Mountain wetlands include a wide range of lakes, rivers, streams, marshes, peatlands and karst DOI: 10.1127/0340-269X/2007/0037-0753 0340-269X/07/0037-0753 $ 4.00 ” 2007 Gebrüder Borntraeger, D-14129 Berlin · D-70176 Stuttgart