Abolition of Heavy Metal Toxicity on Kirchneriella lunaris (Chlorophyta) by Calcium

The green alga Kirchneriella lunaris was incubated with various heavy metals (Cd2+, Co2+, Mn2+, Ni2+) in presence/absence of calcium (Ca2+). The uptake of heavy metal was affected by Ca2+. Growth rate was inhibited by all heavy metals applied. In all Ca2+-containing cultures Kirchneriella exhibited higher rates of growth than those containing heavy metal alone. Photosynthesis/respiration ratio of K. lunaris cells seems to be the determinant in this work. Ca2+ variably abolished the effects of the heavy metals studied. Maximal positive effect of Ca2+ was found with Cd2+ while with Ni2+ it was negligible.