Representative Image.
Credit: DH Photo
Conveyor systems, seen as an environment-friendly alternative to trucks for transportation of minerals in mining sites in forest areas, have significant impact on the wildlife, a study by Environment Management and Policy Research Institute (EMPRI) has found.
EMPRI took up the study in Ballari’s Toranagal where the JSW sought to extend the operation time of its 24-km long mainline pipe conveyor. While the department had allowed operation from 6 am to 6 pm, the company sought to extend it to 2 am.
R K Singh, who retired as the principal chief conservator of forests in June, conducted the study when he was the director of EMPRI. Of the 24-km conveyor, 1.6 km was inside forest land but wild habitat was several folds high in the surrounding area, especially the scrub forest and plantations of Bannihatti and a long stretch of Narihalla which host sloth bears, leopards, four-horned antelopes, Asian palm civets and porcupines.
Even areas 250 metre away from the conveyor saw noise levels of 40 to 50 decibels, the sound levels of a suburban neighbourhood at night.
Studies have identified 40 decibels as the threshold at which species react to noise. The study developed a noisescape keeping the MPC at the centre, where the noise level hit 90 decibels.
Among the birds, common myna and Indian Roller were habituated to the conveyor while cuckoos stayed away from the noisy area. As far as butterflies were concerned, the study observed: “Many species were not found near (conveyor) and extensive growth of invasive species.”
Among the plants, invasive species like Prosopis juliflora (‘Ballari Jali’) and parthenium had occupied the area along the conveyor.
Extending the operation time of the conveyor for 20 hours showed impacts on the amphibians and reptiles. While the calling activity of some of the frogs increased, some were suspected to move away from the habitat. The noise drove some reptiles to bask, led to decrease in foraging activities and increase in resting.
The absence of the baseline data in a place where the conveyor already had an impact for two years prior to the study was sighted as a major limitation. However, the study underscored the problems of increasing operations.
“There is a considerable impact of extended operation (20 hours) on nocturnal birds,” the analysis said, noting a drop in sightings.