Analysis of Pollution Characteristics and Emissions Reduction Measures in the Main Cotton Area of Xinjiang

Abstract

With cotton production in Xinjiang increasing annually, the impact on the environment of agricultural waste produced to improve production has been reflected. This study selected Bozhou of Xinjiang, the main cotton producing region in northern Xinjiang, as the research object, and collected hourly concentration data of six pollutants from 2017 to 2021, and analyzed the spatial and temporal distribution characteristics of each pollutant. At the same time, Morlet wavelet analysis was used to further analyze the variation period of PM2.5 (PM particles with aerodynamic diameters less than 2.5μm) concentration. The Weather Research and Forecasting model coupled with the Community Multiscale Air Quality (WRF-CMAQ) model was used to evaluate the emissions reduction measures for the most polluted month. The results showed that the concentration of particulate matter (PM particles with aerodynamic diameters less than 2.5μm and 10μm) decreased from the southern mountains to the north; moreover, the concentrations of CO (carbon monoxide), NO2 (nitrogen dioxide), and SO2 (sulfur dioxide) in the suburbs were higher than those in the urban center. The concentration of O3 (Ozone) was the highest in summer, while the concentrations of other pollutants were high in autumn and winter. Under the time scale of a = 13, 24, PM2.5 had significant periodic fluctuation. The health risk values of PM2.5 and PM10 in this study were within the scope of the United States Environmental Protection Agency (USEPA) criteria, but it is still necessary to keep a close watch on them. In the context of emissions reduction measures, agricultural sources reduced by 20%, residential sources by 40%, industrial sources by 20%, and transportation sources by 20%; no change in the power source remains. Under these conditions, the daily average value of each pollutant met the first level of the national ambient air quality standard. The research results provide a reference for the local government to formulate heavy pollution emissions reduction policies.

Analysis of Air Pollutants and Their Potential Sources in Eastern Xinjiang, Northwestern Inland China, from 2018 to 2022

“…The elevations of O 3 from 12:00 to 19:00 were due to increased photochemical reactions and the transport of air masses with higher O 3 concentrations [27,50,51]. Considering the variation in sunlight intensity between Xinjiang and the eastern regions of China at the same time, the peak O 3 concentration typically lags behind by 2 to 3 h compared to the eastern regions [52]. None of the six air pollutants showed decreased concentrations during the weekend.…”