LAUSR

Abstract China has recently undergone rapid economic development. However, it is the third-largest acid rain region in the world after Europe and North America, and the acid rain problem in the Yangtze River Delta region is particularly serious. Over recent years, the type of acid rain in the Yangtze River Delta region has changed from sulfuric acid rain (SAR) into nitric acid rain (NAR) because of SO2 and NOX emission controls. This has made ecosystems more complicated. In this study, we used Biolog Eco microplates to investigate the impact of simulated SAR and NAR on soil microbial community function over a year, beginning in March 2015. The results showed that the long-term simulated acid rain treatments reduced the average well color development (AWCD) of the carbon sources in soil microbial communities. Secondly, the effects of acid type on the utilization of polymers and amino acids increased in the later stages of the simulated acid rain treatments. Furthermore, the differences in the utilization of carbon sources caused by the simulated acid rain treatments were mainly due to soil microorganism utilization of L-serine, Tween40, D-mannitol, and N-acetyl-D-glucosamine. Finally, the physical and chemical properties of the soil were not significantly correlated with the utilization of the six C groups. Our results suggested that the two types of acid rain had different effects on soil microbial community function. When the type of acid rain changed, the stability of the ecosystem was challenged and the risk of ecosystem disruption greatly increased.