Smog : The fifth season in central Pakistan
Lahorites witness smog first time
It was the first day of November in 2016 when the people in Pakistan’s eastern city of Lahore witnessed sunlight getting unusually yellowish, the pungent air caused irritation in the eyes and throats of people. It was a thick mass of toxic fog that had not only reduced the visibility but also made the atmosphere suffocating for Lahoris. The city had been experiencing foggy conditions for centuries during the months of November and December but it was the first time that there was fog mixed with smoke. Since then, the smog has become an annual feature in Lahore and the central Punjab, a spell referred by some Lahoris as the fifth season of the year. A similar situation is witnessed in Indian capital, New Delhi, some 500 kilometres away from Lahore.
What turns generally pleasant fog into smog?
Initially, it was thought that coal fired power plants dotted along international border in adjoining northern Indian states of Punjab and Rajasthan were responsible for causing smog in Lahore and other parts of central Punjab. However, the images released by America’s upper space research organization, NASA, showed that high levels of “fires and thermal anomalies” in Indian states of Punjab and Haryana due to burning of stubbles of paddy crop increased the level of toxic air in central Punjab in Pakistan along with Indian capital city, New Delhi.
“Fog transforms into smog after it gets mixed with smoke or carbon particles from burning of crops residue by farmers, especially the stubble of paddy crop,” says Naseem Shah, Director Punjab’s Environment Protection Department.
In addition, smoke emitted by from brick kilns and the exhausts from the hundreds of thousand automobiles in big cities such as Lahore, Faisalabad and Multan make the situation worse. Agriculture sector, however, is considered the major source of pollutants during dry and cold weather in October and November.
The term smog refers to the environmental conditions characterized by presence of envelop of toxic but foggy air over a particular region. Fog along with the toxic compounds such as Nitrogen Oxide, Sulphur Oxide and Ozone create smog. Vehicles, Industries, forest fires and photochemical reactions are main contributors to smog, which is a main health issue in Pakistan. The two main cities of Pakistan, Lahore and Faisalabad, are main victims of smoggy conditions every year and its intensity is increasing with each passing year, according to the environmentalists.
According to a report of Food and Agriculture Organization (FAO), satellite data of atmospheric pollutants are being widely used globally as well as in South Asia in the decision-making and environmental management activities of public, private sector and non-profit organizations. Using Satellite based measurements to monitor and identify the causes of increased levels of smog. The findings identify the relationship between smog and the practice of paddy residue burning practices by farmers in the rice belt of Punjab.
It is estimated that 32 million tons (30 billion kgs) of leftover straw burnt by farmers in the Indian states of East Punjab and Haryana every year are the main reason behind smog in the plains of central Punjab in Pakistan. It has been an age-old practice to burn residue of crops, but ever-increasing activity and increase in population have worsened the situation, sending its effect across the border in Pakistan, engulfing Lahore and other parts of Pakistani Punjab.
It is estimated that the levels of the dangerous particulates known as PM2.5, small enough to penetrate deep into the lungs and enter the bloodstream, have reached 1,077 micrograms per cubic meter — more than 30 times what Pakistan’s government considers the safe limit.
According to Space and Upper Atmsophere Research Council (SUPARCO) , the organization entrusted with space research in Pakistan the major reason for the smog is extraordinarily high concentrations of ammonium sulphate. The results have serious implications on human health. The fog has impact on agriculture, general economy and global and regional climate. Smog considered to be an outcome of bad practices in agriculture sector, may affect the productivity in the farming especially by causing decline in vegetables, fruit and major crops yields.
Dense urban areas suffer more from smog because of huge number of vehicles, industries and combustion of different types of fuel. So smog has serious negative impacts on people, plants and animals.
Ozone and peroxyacetyl nitrate (PAN) get produced during the mixing of pollution and fog, and that is very harmful to vegetables, fruits, plants and crops depending on concentration and duration of exposure. Nitrous Oxides (NOX) and Sulphur Oxides (SOX) get mixed in the smog. These gases kept constantly affecting the vegetation during the last one decade
According to research made by University of Agriculture Faisalabad, in some cases, exposure to pollutants in air or smog, particularly SO2, causes stomata of leaves to close. This closing protects the leaf against further entry of the pollutants, but it also stops photosynthesis, a process which creates nutrition for the whole plant. Smoggy conditions badly affect the crops of Tomato, potato, string beans, snap beans, pinto beans, tobacco, soybeans, cantaloupe, beets, sunflower, carrots, sweet corn, gourds, green peas, turnips, grapes, peaches, and strawberries.
How to combat smog through biological means
Botanists believe that 11 plants have the inherent ability to eliminate the pollution and smog from the air. These include-Areca Palm, Money Plant, Spider Plant, Purple Waffle Plant, Bamboo Palm, Variegated Wax Plant, Lily turf, Boston Fern, Dwarf Date Palm, Moth Orchids and Barberton Daisy. These plants should be grown more and more to reduce the pollution. People should be encouraged to grow these plants in their homes, gardens and offices.
The effective use of the microorganisms to eliminate the pollution from the environment is also recommended by bio-technologists. Bio-adsorption is a new process in which “bioadsorbers” (those which absorb pollutants biologically) are being made from the renewable materials and work as eliminator of toxic heavy metals. Genetically engineered grasses and trees may be an excellent source of pollution removal. Phytoremediation is the process in which plants are engineered in such a way that they become capable to absorb the toxic metals and other pollutants and convert them into the harmless compounds. Now there is need of biotechnologists and other scientists to start work on this issue and play their role to save air and prevent the harmful effects of air pollution to humans.
How agriculture and other sectors are stopped from polluting environment?
Besides the biological means, the use of mechanical tools can also be helpful in checking smog in Pakistan as well as India. Rice Research Institute (RRI), Kala Shah Kaku has recently developed a chopper that can help shred the stubbles of paddy in such a way that these are mixed in soil before the cultivation of other crops including wheat. In this way, farmers will not need to burn crop residue. Secondly, the governments on both sides of the border can take administrative measures such as banning the burning of crop residue in order to bring down the level of NOX and SOX in the air.
Introduction of zig zag technology in brick kilns have brought down the emission of hazardous gases from this source by 70 percent. The use of high octane fuel and strict enforcement of regulation for high maintenance of vehicles could be helpful in checking emissions from motor vehicles.
“We have recently adopted the Zig Zag technology of Nepalese origin; It has been successful experience in bring down the level of hazardous emissions,” says Haji Muhammad Ikram, the office bearer of Pakistan Brick kiln owners Association.
Less incidence of smog in central Pakistan during the year 2018 have proved that these all acts are doable provided there is a political will to do so.