P. Lupoae


RESEARCHES CONCERNING THE DISTRIBUTION OF HYDROPHYTES AND HELOHIDATOPHYTES IN AQUATIC ANTHROPOGENE ECOSYSTEMS IN WHICH THERE ARE STOCKED CTENOPHARINGODON IDELLA

P. Lupoae, V. Cristea, Mariana Lupoae

Abstract
    The aim of this paper consists in identification and determination of some plant groups, from hydrophytes and helohidatophytes groups, which are part of the aquatic anthropogene ecosystems, as a potential source of food for Ctenopharingodon idella (Valenciennes 1844). For a period of 4 consequent years the distribution of taxa has been studied in the Lower Prut Flood Plain, regarding the description of the dominance of plants which cover the water surface and its depth too. The botanical samples harvested from the designated field have been determined on the basis of information from specialty literature and personal researches, using the standards from Flora Europaea. The results have been expressed as average ± standard deviation. (SD). The statistical work of the dates were processed through the "t" test Student unegual variances and the limit of signification of the changes which is considered to be at p=0.05 and therefore differences at p<0.05 significant and p>0.05 insignificant. From the bioforms analysis, results that 40 fitotaxons (22 hydrophytes and 18 helohidatophytes) of which 2 species are signaled with the status of Threatened European Taxons: Salvinia natans (L.) All. and Trapa natans L. The percentage determination of occupation rate with vegetation across the water surface and the nominal distribution (by species) led to identification of the dominant plants. Our researches resulted in the fact that Ctenopharingodon idella acts during its feeding a election towards hydrophytes and helohidatophytes, displaying a preference for plants from the Potamogeton sp. and Najas sp. genus and other types (Carex sp., Phragmites sp. and Typha sp.) but even in their early period of development.

Key words: grass carp, hydrophytes, food election