Acid rain in China mainly occurs south of the Yangtze River, and it is scattered only in the north. This is because sand and dust weather is common in the north, and sand and dust from the desert and local soil are more alkaline. From this we can infer:. ['Less acidic pollutant emissions in areas north of the Yangtze River.', 'Soils in the south of the Yangtze River are less alkaline.', 'Sand and dust weather can effectively reduce the chance of acid rain.', 'Sand and dust weather is less likely to occur in areas with acid rain.']