Tez özetleri Astronomi ve Uzay Bilimleri Anabilim Dalı

Investigation Of Heavy Metal Absorption And Accumulation In Some Algal Species Isolated From Lake Sapanca And Küçükçekmece

In this study, it is investigated the heavy metal absorption of Monoraphidium contortum (Thur.) Kom.-Legn.and Mougeotia sp., which is isolated from Lake Sapanca and Küçükçekmece, and the effects of heavy metals on algal growth and chlorophyll-a. For this purpose, the series (0.2, 0.4, 0.8 and 1.6 g/ml) of heavy metals (Cobalt, Nickel and Zinc) were added. Subsamples were taken each 5 min, 30 min, 1 day, 3 days and 7 days after heavy metal addition to observe the effects of heavy metals on M. contortum and Mougeotia sp. and the absorption capacity, chlorophyll-a contents and algal biomass were calculated.

According to the results, maximum absorption of cobalt by M. contortum and Mougeotia sp in all concentrations was measured at the end of first day of addition. The important point is, in M. contortum cultures which had 0.2, 0.4, 0.8 g/ml cobalt, chlorophyll-a concentrations increased at the end of seventh day and the rates of increment were 36 %, 32 % and 1 % in the addition of 0.2, 0.4, 0.8 g/ml cobalt, respectively. On the other hand, in Mougeotia sp. cultures 23 % increase in chlorophyll-a concentrations were measured in 0.8 g/ml cobalt addition at seventh day.

While in nickel added to the M. contortum cultures, absorption reached to maximum at the end of first day, absorption rate was low in Mougeotia sp. cultures. Maksimum absorption was measured in Mougeotia sp. cultures at the end of seventh day in the 1.6 g/ml. Chlorophyll-a concentrations was higher in M. contortum than Mougeotia sp. Like Cobalt addition, nickel addition has also resulted in an increase in chlorophyll-a

concentrations in M. contortum cultures. The maximum loss of biomass was recorded in 1.6 g/ml concentration after three days.

In zinc addition, absorption rate was higher in M. contortum cultures than Mougeotia sp. cultures. Chlorophyll-a concentrations reached to maximum value at the end of seventh day like other heavy metals. In addition of 0.2, 0.4, 0.8 and 1.6 g/ml to M. contortum cultures, biomass was increased to 4, 20 and 1 %, respectively. On the other hand, biomass was decreased to 3 % by the addition of 0.8 g/ml of zinc. By the addition of 0.2 g/ml zinc to a culture of Mougeotia sp., increase in biomass was only 8 % after seven days.