By Our Reporter
SHILLONG, April 25: A study based on field observations in Meghalaya has found that shifting cultivation, or jhum, accounts for up to 27 per cent of air pollution in the state during pre-monsoon months, driven by sharp spikes during active burning.
Published in the journal Atmospheric Environment, the research draws from sites in West Garo Hills and shows that pollution levels rise abruptly when multiple jhum fields are burned simultaneously. During these peak windows, PM2.5 concentrations surge alongside gases such as carbon monoxide and nitrogen oxides.
The study recorded particulate levels rising between 15.6 and 17 times, with lung deposition increasing nine to 10 times compared to non-burning periods.
Satellite observations further indicate clusters of fire activity aligning with aerosol spikes across the state and the wider Northeast.
Researchers pointed out that evolving jhum practices, specifically shorter fallow cycles, are leading to more frequent burning and higher cumulative emissions.
However, the absence of continuous air quality monitoring in many of Meghalaya’s hill districts means these episodic pollution events are rarely captured in official datasets, limiting long-term health assessments.
While quantifying the environmental impact, the study says that jhum remains integral to livelihoods in Meghalaya. Instead of abandoning the practice, the researchers have called for improved land management, adaptive cultivation cycles and the establishment of stronger monitoring systems.
