Intensification of smog episodes, following harvesting of paddy crops in agricultural plains of the Indus basin in the Indian subcontinent, are often attributed to farming practice of burning standing stubble during late autumn (October, November) months. Biomass burning (paddy stubble residual) is a preferred technique to clear farmlands for centuries by farmers in that basin. However, despite stable agricultural landholding and yield, smog is being increasingly associated with burning agricultural biomass, thus creating a paradox. Here, we show that the concentration of smog (NOx, PM_2.5, SO₂) in the ambient air exceeds the safe threshold limits throughout the entire year in the region. This study argues that agricultural biomass burning is an ephemeral event in the basin that may act as a catalyst to a deteriorated air quality in the entire region. Results further demonstrate that simultaneous saturation of air pollutants along with high ambient moisture content and low wind speeds following the monsoon season are strongly related to aggravated smog events. Findings from this study should help make holistic mitigation and intervention policies to monitor air quality for sustainability of public health in agricultural regions where farming activities are a dominant economic driver for society.

中文翻译：

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印度河流域燃烧农业生物质的环境协会

在印度次大陆印度河流域的农业平原上收获稻谷之后，烟雾的发作加剧，通常归因于深秋（十月，十一月）月份燃烧秸秆的耕作方式。生物质燃烧（稻茬残渣）是该流域农民数百年来清理农田的首选技术。然而，尽管农业土地占有率和产量稳定，但雾霾与燃烧农业生物质的联系日益密切，因此造成了悖论。在这里，我们表明烟雾的浓度（NOx，PM _2.5，SO ₂）在整个区域内全年超过安全阈值限制。这项研究认为，农业生物质燃烧是流域内的短暂事件，可能是整个地区空气质量恶化的催化剂。结果进一步表明，在季风季节之后，空气污染物的同时饱和以及高环境湿度和低风速与加剧的烟雾事件密切相关。这项研究的结果应有助于制定全面的缓解和干预政策，以监测空气质量，以确保农业活动是社会经济的主要驱动力的农业地区的公共卫生可持续性。