Stubble burning is a common agricultural practice that involves setting fire to crop residue left after harvest. It has been used for centuries to clear fields and prepare for the next planting season. And so it contributes to global warming and climate change to a large extend. In this blog, we will explore the impacts of stubble burning on climate change. Also why it is an overlooked contributor to global warming.
Impacts
Stubble burning releases large amounts of carbon dioxide (CO2), methane (CH4), and other greenhouse gases into the atmosphere. These gases trap heat in the Earth’s atmosphere, causing global temperatures to rise and leading to environmental problems. The Intergovernmental Panel on Climate Change (IPCC) estimates that agriculture is responsible for around 25% of global greenhouse gas emissions, with a significant portion coming from stubble burning.
Air
The air quality in the exposed environment is seriously threatened by burning stubble. It should note that agricultural burning significantly lowers air quality since it releases gaseous and aerosol pollutants. The population under exposure to PM2.5 and PM10 is said to have the most significant impact on their health. The World Bank conducted a source apportionment study on PM2.5 for several Indian towns in 2001. They found that, in Delhi, Mumbai, Chandigarh, and Kolkata, respectively. Biomass burning contributes 9–28%, 23-29%, 24%, and 37–70% of the PM2.5 concentrations.
When comparing the burning and non-burning periods in Delhi in 2011. It was discovered that there was a 300 mg/m3 rise in PM2.5 concentration during the rice and wheat stubble-burning seasons, respectively. During the burning events, an increase in the hourly PM10 concentration. In Mandi-Gobindgarh city, Punjab, PM10 and PM2.5 concentrations rose by 86.7% and 53.2% for rice and wheat burning seasons in 2015. In Patiala city, they conducted a source apportionment analysis. And found that burning stubble contributes between 100 and 200 g/m3 of PM10 to the city’s air pollution.
Burning stubble is a significant source of air pollution in India, while not the leading cause. The composite emissions come from a mix of point and nonpoint sources. According to Sharma and Dhiskit (2016), these sources include businesses, power plants, automobiles, construction, and indoor pollution. In contrast to transportation emissions, which contain 17% PM2.5, 13% PM10, 53% NOx, and 18% CO, Guttikunda and Gurjar (2012) discovered that emissions from industrial sources contain 15% CO, 14% PM2.5, and 23% SO2. However, emissions from burning stubble are far less; they only include 14% CO and 12% PM2.5.
Soil
By burning the vital nutrients in the soil, stubble burning has negative impacts on soil production. And therefore its consequences on air quality. Additionally, it elevates the soil temperature to around 42 °C, which kills or displaces the significant soil microorganisms at a depth of about 2.5 cm. This results in an additional cost for compost or fertilizer to restore soil fertility. Burning snags depletes the soil of micronutrients and nitrogen, phosphorus, and potassium (NPK), three critical elements. For instance, burning rice stubble results in an annual loss of roughly 0.445 Mt of NPK. Burning wheat stubble results in an annual loss of 0.144 Mt. And burning sugarcane trash results in an annual loss of 0.84 Mt.
Environment
Stubble burning also has significant environmental consequences. And it reduces soil fertility and degrades soil health Thus decreasing crop yields and requiring more effective use of synthetic fertilizers. This, in turn, leads to further greenhouse gas emissions and more significant environmental degradation.
Agricultural productivity
Burning crop residue has negative repercussions on the agriculture industry. Strong empirical support exists for the claim that air pollution impacts food output. Pollutants may have a direct or indirect impact on agricultural output. Injury to leaves, damage to grains, or heavy metal absorption are examples of direct consequences. Nitrogen oxide, for instance, can deteriorate and discolour plant tissue. Plant death might result from the production of acid rain, which has detrimental effects on soil and plants. Plants exposed to particle pollution for an extended period may develop chlorosis or bifacial necrosis. Creating conducive conditions for spreading diseases or pests is one example of an indirect effect. High concentrations of SO2 and NO2 are, for instance, conducive to the growth of insect aphids.
Mortality rates
In recent years, air pollution-related fatality rates have been steadily rising. For instance, between 1990 and 2015, the number of fatalities related to air pollution in South Asia grew from 1.1 million to 1.2 million. Residents of the Indo-Gangetic Plain regions were said to have a life expectancy roughly seven years lower than that of residents of other Indian regions. According to reports, the IGP saw an increase in air pollution of around 65% between 1998 and 2016, and particulate matter concentrations were twice as high as the national average. According to reports, PM2.5, in particular, is the deadliest of all pollutants, and nearly 50% of India’s population is exposed to it. To a high level of PM2.5 with a concentration above the WHO limit (35 µg/m3), while about 49% of the exposed population do not have access to good healthcare (Liu et al., 2018).
Human Health and Well being
Numerous studies have shown a connection between air pollution and the risk of various health disorders, particularly in children, pregnant women, the elderly, and those with pre-existing conditions. Air pollution can cause severe neurological, cardiovascular, and respiratory conditions and skin and eye discomfort. It may have fatal consequences in certain circumstances, especially if the exposed victim already has respiratory issues. In certain situations, long-term exposure to high levels of air pollution can result in irreversible health damage, such as the onset of lung conditions, including cancer, emphysema, COPD, bronchitis, and capacity loss. Farmers who have been exposed to stubble smoke complain of eye and lung discomfort and have incurred high medical costs
Impacts on Economic growth
Air pollution negatively affects a nation’s economy and its adverse effects on health and the environment. Because a nation’s economic and technical advancements determine how well air pollution is managed, it follows that rising pollution has a variety of adverse effects on that nation’s economy. Due to the rise in air pollution over the past few years, Delhi has seen a 25–30% decline in visitors visiting the city. In 2018, the cost of air pollution to India’s economy ranged from 4.5 to 7.7% of GDP, and when extrapolated to 2060, the figure increased to around 15%. Air pollution also reduces workers’ productivity in other areas by making them ill and difficult to see.
According to the World Bank, in 2013, air pollution cost the global economy $225 billion, with poorer nations bearing the lion’s share of the burden. The Indian government estimated that managing air pollution and providing for its well-being would cost around $14 billion annually.
Climate
The impact of stubble burning on climate change is particularly acute in developing countries such as India and China, where it is still a common agricultural practice. Burning crop residues in these countries contribute to air pollution, smog, and health problems for the local population. It also exacerbates climate change, as the large amounts of greenhouse gases released into the atmosphere increase global warming.
Due to the release of greenhouse gases like CO2 and CH4, which can potentially contribute to global warming, emissions from stubble fires directly impact weather and climate. According to statistics, the agricultural industry contributes between 17% and 32% of the world’s total yearly greenhouse gas emissions. In 2017, burning crop stubble resulted in emissions of 171.37 Tg of CO2, 0.706 Tg of CH4, and 0.073 Tg of N2O. India produces 658.823 Tg of CO2, equivalent or roughly 12.2% of the world’s greenhouse gas emissions. According to reports, the bad air quality and altered weather patterns contributed to India losing around 36% of its anticipated annual wheat yield in 2018.
Solutions
Despite these impacts, stubble burning remains a common practice in many parts of the world. This is partly due to the need for more affordable and sustainable alternatives and cultural and historical traditions. However, there are solutions available that can help to reduce the impact of stubble burning on climate change.
- One solution is to encourage the adoption of conservation agriculture practices, such as zero-tillage and crop rotation, which reduce the need for stubble burning and help to build soil health. These practices can also help to reduce greenhouse gas emissions by sequestering carbon in the soil.
- Another solution is to invest in renewable energy sources such as biogas and biofuels, which can be produced from crop residues and other agricultural waste. This reduces greenhouse gas emissions and provides clean energy for local communities.
Conclusion
In conclusion, stubble burning is an overlooked contributor to global warming and climate change, and it has significant impacts the environment, human health, and agricultural productivity. However, solutions available can help reduce the effect of stubble burning and promote sustainable farming practices. By investing in these solutions, we can help to mitigate the impacts of climate change and create a more sustainable future for all.