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The present study was concerned with the effect of some heavy metals (Lead, Cadmium, Copper, and Zinc) and their toxicity individually on the growth of green alga Scenedesmus dimorphus which belongs to the phylum of Chlorophyta .This was achieved depending on the absorption values to measure the liv...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
| Published: |
University of Thi-Qar
2019-06-01
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| Series: | مجلة علوم ذي قار |
| Online Access: | https://mail.jsci.utq.edu.iq/index.php/main/article/view/489 |
| Summary: | The present study was concerned with the effect of some heavy metals (Lead, Cadmium,
Copper, and Zinc) and their toxicity individually on the growth of green alga Scenedesmus
dimorphus which belongs to the phylum of Chlorophyta .This was achieved depending on the
absorption values to measure the living biomass of the alga,and then computing the growth
average and doubling time when exposing the alga to these metals.
The effective median concentration EC50 of each of these four metals were also computed.The
concentrations (15, 20, 25, 30)mg/l of lead were used. Results showed that exposing the alga to
the concentration (30) mg/l caused an acute decrease in growth. The other concentration (15, 20,
25)mg/l also led to a gradual decrease in growth. Treating the alga with(0.05, 0.1, 0.5, 1)mg/l
concentration of Cadmium the number of cells decreased in case of three concentration (0.05,
0.1, 0.5) mg/l. The decrease in growth was greater and clearer in case of the concentration (1)mg/l
concentration Cadmium.As for Copper the concentrations (0.5, 1, 1.5, 2)mg/l and the
concentration (2)mg/l had the greatest effect in deceasing growth. Results also showed that the
concentration (3)mg/l of zinc had the greatest effect in decreasing the growth on compared with
the other concentration (0.7, 1, 2, 3)mg/l.The toxic effect of cadmium proved greater than that of
zinc copper, and lead in terms of the effective median concentration which indicated (0.23, 0.396,
0.35, 6.8) mg/l after treating the alga with lead, cadmium, copper, and zinc for (144) hours.
Results were then analyzed statistically by using the variance analysis (ANOVA) and testing the
difference between the treatments according to the Least Significant Difference (LSD)in p> 0.05. |
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| ISSN: | 1991-8690 2709-0256 |