Search results for "Mountain stream"
showing 2 items of 2 documents
Biological indices applied to benthic macroinvertebrates at reference conditions of mountain streams in two ecoregions (Poland, the Slovak Republic)
2013
The study was carried out from 2007 to 2010 in two ecoregions: the Carpathians and the Central Highlands. The objectives of our survey were to test the existing biological index metric based on benthic macroinvertebrates at reference conditions in the high- and mid-altitude mountain streams of two ecoregions according to the requirements of the EU WFD and to determine which environmental factors influence the distribution of benthic macroinvertebrates. Our results revealed statistically significant differences in the values of the physical and chemical parameters of water as well as the mean values of metrics between the types of streams at the sampling sites. RDA analysis showed that the t…
A STUDY ON THE POSSIBLE EFFECT OF TWO CRAYFISH SPECIES ON EPILITHIC ALGAE IN A MOUNTAIN STREAM FROM CENTRAL SPAIN
2006
The effects on epilithic algae of increasing densities of two crayfish species, Austropotamobius italicus and Pacifastacus leniusculus, the latter recently introduced in Spain, have been monitored using riverine enclosures, within a large experimental study on crayfish-macrobenthos interactions in a mountain stream. A 3-month test was carried out for each species using crayfish densities comprising between 0-5 individuals/m2 kept in 1-m2 enclosures. Epilithon was sampled periodically within the enclosures and chlorophyll a, b and c were measured by spectrophotometry. Neither statistically significant positive nor negative effects were observed on algal abundance (Chl concentrations) during …