Published Paper Details:

The total chlorophyll content increased within 15 days of exposure in the control set and the value increased further on 15th day of recovery. A maximum of 7.3% increase was recorded on 12th day and on 15th day 3.9% increase over the control value was marked in conc. X set. When the exposed alga was transferred to toxicant free medium, the chlorophyll content increased insignificantly. A maximum of 25.6% decrease was recorded on 12th day and on 15th day 35.3% decrease over the control value was marked in conc. Y set. A maximum of 89% decrease was recorded on 12th day and on 15th day 97.1% decrease over the control value was marked in conc. Z set. The percent decrease increased with the increase in exposure period, where a positive correlation was marked. A maximum of 97.06% decrease was recorded on 15th day of exposure in conc. Z set. No significant recovery was recorded in conc. Y set and no recovery was marked in concentration Z set, when the exposed alga was transferred to toxicant free nutrient medium, rather higher depletion was noted. At conc. X, the carotenoid content increased at all exposure periods, when compared to the control value except on 3rd day. Insignificant partial recovery was recorded in conc X and no recovery was marked in conc.Y, when the exposed alga was transferred to toxicant free, nutrient medium. In case of conc.-Z, highly significant decrease in the carotenoid level was noted. In conc. X, the ratio value was significantly high when compared to control value at all exposure periods and recovery periods. Interestingly, the ratio value decreased in conc. Y at all exposure and recovery periods when compared to control and conc.-X. From the data, it was evident that the ratio value can be an indicator of stress in plant systems. 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.