Biological Activity of CalotropisproceraGrown Under High Voltage Transmission Lines in Jeddah Province, Saudi Arabia
Electromagnetic field (EMF) may cause biological changes to wild plants growing around or near the electricity towers. To evaluate this argument a field study was conducted at north Jeddah city during 2013-14. A number of plant species found in the study areas, but Calotropisprocera L. was selected for this study. Sampling was performed from four different towers for Electricity high-pressure transmission lines north Jeddah province, build at different years (1981, 1991, 2008, and 2013). Three places has been selected away from the tower, starting from the bottom of the tower for this study, zero m (under the tower), 50 m and 100 m away from centre. A control site was also chosen far from electricity towers and lines. Plant morphology (height, number of branches, shelter width and leaf area), physiological activity (intercellular CO2, transpiration rate, net photosynthesis rate and chlorophyll contents) and some ion content in soil and plant leaves were measured. The results show that the plant health was improved morphophysiologically at the center and older installations. Moreover by decreasing the distance from 100 m to 0 m, significant influence was found, it may be attributed to enhance exposure of electromagnetic field, as a consequence plant revealed some relief in terms of growth.