Toxicological impacts of cadmium chloride on the primary productivity of a blue-green alga in vivo under Controlled conditions

Experiments were conducted at different concentrations of cadmium chloride to assess the impacts of cadmium chloride on the productivity of a blue-green alga, Anabaena cylindrica. The exposed alga could accumulate significant amount residual cadmium in its body within 15days of exposure and significant excretion of cadmium was observed during recovery period. Significant depletion in photosynthesis rate (PR) & respiration rate (RR) was observed in the exposed alga at higher concentrations of cadmium chloride compared to control alga. Drastic depletion in gross primary production (GPP) was computed in the experimental study with the accumulation of cadmium in the algal body. Partial recovery of the 15d exposed alga was noted after a prolonged exposure period. This crop field inhabiting tolerant alga suffers because of effluents of the paper industry which contained cadmium along with mercury and lead. The residual cadmium level increased with the increase in exposure period in all three tested concentrations. During recovery period partial recovery was noted. Prolonged recovery period indicated reversal of inhibition. The residual cadmium level decreased significantly after 30days of recovery and 60days of recovery.