Abstract:
Over recent years, crop residue burning has become a regular agricultural activity in developing
countries due to varying economic and social reasons. The burning of crop residue in the open
field has become a significant concern for both air pollution and climate change mitigation efforts
worldwide. To estimate air pollution caused by crop residue burning in Pakistan, an emission
inventory was developed based on district-level crop production data during the period 2001-
2020. Spatial distribution of quantified emissions was achieved by using MODIS Active Fire Data
(MOD/MYD14A1) at 1-day temporal and 1×1 km 2 spatial resolutions in this study. Two major crop
residues, i.e. wheat straw and rice straw, were considered. Total annual emissions of CO 2 , CO,
CH 4 , NMVOCS, N 2 O, NH 3 , SO 2 , NOx, PM 2.5 , PM 10 , OC and BC in 2020 were 0.12, 0.009, 0.0007,
0.0006, 2.13E -05 , 0.0002, 5.09E -05 , 0.0003, 0.001, 0.0004, 0.0009, and 7.28E -05 Tg respectively.
Spatially, throughout the study period 2001-2020, Dadu, Larkana and Layyah districts exhibited
the highest emissions as compared to other districts of Pakistan. Temporally crop residue burning
was dependent on the harvesting seasons with highest concentration in May followed by February,
November, and December month. There was a significant increase in pollutant emissions over 20
years ranging from 18% for N 2 O to 26% for NH 3 . The environmental cost of Kharif was highest in
2019 for Sindh and 2020 for Punjab with the values 1.79E +09 and 8.32E +08 respectively. While the
economic cost of rabi crops was highest in 2013 with a value of 2.22E +08 In Sindh. The observed
trend suggested that emissions from crop residue burning will continue to rise in the future due to
the absence of policy intervention and strict action.
