Abstract
The negative impacts of air pollution have made monitoring of air quality increasingly important, especially in heavily industrialized areas such as the South Durban Basin (SDB), in South Africa. Bioindicators such as trees can complement conventional air quality monitoring and be used to prioritise vulnerable areas. This study assessed the utility of Brachylaena discolor DC. tree leaves as a bioindicator of sulfur dioxide pollution. This involved correlating ground level sulfur dioxide concentrations ([SO2]) with B. discolor leaf sulfate concentrations ([sulfate]) at three industrial (treatment) sites within the SBD and control site at which [SO2] was significantly lower for all four seasons. Based on this significant positive correlation between the aforementioned (p = 0.005; ρ = 0.667) leaf sulfate levels were related to various biochemical (intracellular hydrogen peroxide production, total aqueous [TAA] and enzymic antioxidants [superoxide dismutase and catalase], lipid peroxidation [LPO] and electrolyte leakage), physiological (leaf chlorophyll fluorescence [LCF] and relative chlorophyll content) and morphological (leaf area [LA]) biomarkers of stress measured on leaves from trees at the treatment and control sites. Annual [SO2] and leaf [sulfate] at the treatments were significantly (p < 0.05) higher than the control and high by global standards. TAA, LPO, electrolyte leakage, LCF, and LA were significantly (p < 0.05) correlated with seasonal [sulfate]. Except for superoxide dismutase, catalase and relative chlorophyll content all other biomarkers could differentiate between the treatment sites and the control. However, TAA, electrolyte leakage and LA were the only biomarkers sensitive enough to reflect differences in annual [sulfate] across the treatment sites; these should be used to establish B. discolor leaves as a bioindicator of SO2 pollution.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
