| Effects of Lead (Pb) on Biomass and Chlorophyll of Bruguiera sexangula (Lour.) Poir. Seedlings |
| Paper ID : 1317-IGA |
| Authors |
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Md. Mushfiqure Rahman Moon * Department of Forest Science, Institute of International Forestry and Forest Products,Technische Universität, Dresden, Germany |
| Abstract |
| Background and Aim: Mangrove ecosystems, vital for coastal protection and biodiversity, are increasingly threatened by lead pollution from urban and industrial activities. Bruguiera sexangula, a key species in the Sundarbans, is sensitive to Pb which can impair photosynthesis, nutrient uptake and growth. This study aimed to investigate the effects of Pb on the growth and chlorophyll content of B. sexangula seedlings to determine dose dependent toxicity. Materials and Methods: Seven Pb concentrations (0, 5, 10, 20, 30, 40, and 50 mg/L) were applied to B. sexangula seedlings using Pb(NO₃)₂ in modified Hoagland's solution with salinity adjusted to 15 ppt. Propagules were collected from the Sundarbans, raised in nursery beds and transplanted into experimental pots with coarse sand. The experiment, conducted under semi-greenhouse conditions for 8 months, measured growth parameters like height increment and fresh biomass. Chlorophyll content was extracted and quantified using DMSO, and statistical analysis was performed using one-way ANOVA and Duncan's Multiple Range Test. Results: The results indicated that Pb exposure significantly reduced the height, collar diameter and biomass of B. sexangula seedlings, with the most pronounced effects observed at the highest concentrations (40 and 50 mg/L). The chlorophyll content of the seedlings also decreased significantly as Pb concentration increased, indicating impaired photosynthetic efficiency. Statistical analysis revealed highly significant differences (p < 0.001) in all growth parameters and chlorophyll content among the treatments with the control group (0 mg/L Pb) showing the highest growth and chlorophyll values. Conclusion: Lead contamination significantly impairs B. sexangula seedling growth and chlorophyll content with concentrations above 20 mg/L causing substantial physiological damage. These results highlight the vulnerability of mangrove ecosystems to Pb pollution and underscore the need for effective monitoring and remediation strategies. |
| Keywords |
| Bruguiera sexangula, Lead toxicity, Mangroves, Biomass, Chlorophyll |
| Status: Accepted |
