Impact of socioeconomic and meteorological factors on reservoirs’ air quality: a case in the Three Gorges Reservoir of Chongqing (TGRC), China over a 10-year period

The Three Gorges Dam’s construction and industrial transfer have resulted in a new air pollution pattern with the potential to threaten the reservoir eco-environment. To assess the impact of socioeconomic factors on the pattern of air quality vairation and economical risks, concentrations of SO₂, NO₂, and PM₁₀, industry genres, and meteorological conditions were selected in the Three Gorges Reservoir of Chongqing (TGRC) during 2006–2015. Results showed that air quality had improved to some extent, but atmospheric NO₂ showed an increased trend during 2011–2015. Spatially, higher atmospheric NO₂ extended to the surrounding area. The primary industry, especially for agriculture, had shown to be responsible for the remarkable increase of atmospheric NO₂ (p < 0.01) due to the direct burning of agricultural straws and the emission of livestock breeding. The improvement of regional industrial structure and industrialization benefited air pollutant reductions, but construction industries had inhibited the improvement of regional air quality. In the tertiary industry, the cargo industry at ports had significantly decreased atmospheric NO₂ as a result of eliminating the obsoleted small ships. Contrarily, the highway transportation had brought more air pollutants. The relative humidity was shown to be the main meteorological factor, which had an extremely remarkable relation with atmospheric SO₂ (p < 0.01) and a significant correlation with atmospheric NO₂ (p < 0.05), respectively. In the future, the development of agriculture and livestock breeding would make regional air quality improvement difficult, and atmospheric SO₂, NO₂, and PM₁₀ deposition would aggravate regional soil and water acidification and reactivate heavy metal in soil and sediment, further to pose a high level of ecological risk in the TGRC and other countries with reservoirs in the world.