Algae as Bioindicators

In three different experiments, the influence of various concentrations of zinc, copper and crude oil on productivity and species composition in algal periphyton communities was investigated using indoor artificial streams. The effects of zinc, copper and crude oil on community productivity were assessed by measuring biomass, ash-free dry mass (AFDM), chlorophyll-a, species composition, relative abundance, biovolume and bioconcentration factor. Generally in artificial streams with zinc, copper and crude oil there was a significant (p<0.05) reduction of chlorophyll-a, dry mass and AFDM. Species diversity and relative abundance of periphyton species changed drastically under the influence of zinc, copper and crude oil. In another study, concurrent evaluations of water quality in the River Gharasou have been carried out using species composition and several aspects of primary productivity. Five sites along River Gharasou were sampled monthly from April to September. Results obtained from this part of the study resulted in development of a Trophic Diatom Index for the River Gharasou.