Response and driving factors of soil enzyme activity related to acid rain: a meta-analysis

• Published in: Environmental science and pollution research international Vol. 30; no. 48; pp. 105072 - 105083
• Main Authors: Shi, Zhaoji, Zhang, Jiaen, Zhang, Huicheng, Wei, Hui, Lu, Tiantian, Chen, Xuan, Li, Hongru, Yang, Jiayue, Liu, Ziqiang
• Format: Journal Article
• Language: English
• Published: Berlin/Heidelberg Springer Berlin Heidelberg 01.10.2023; Springer Nature B.V
• Subjects: Acid rain; Acid Rain - analysis; Acidic soils; Acidification; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Biomass; Earth and Environmental Science; Ecosystem; Ecosystem models; Ecotoxicology; Environment; Environment models; Environmental Chemistry; Environmental Health; Enzymatic activity; Enzyme activity; Enzymes; Hydrogen; Meta-analysis; Microorganisms; Multivariate statistical analysis; Rain; Review Article; Rhizosphere; Soil - chemistry; Soil Microbiology; Soil pH; Soil pollution; Soils; Waste Water Technology; Water Management; Water Pollution Control; Rhizosphere; Simulated acid rain; H; addition rate; Acid deposition; Soil acidification; Microbial biomass; H+ addition rate
• ISSN: 1614-7499; 0944-1344; 1614-7499
• DOI: 10.1007/s11356-023-29585-4

As a global pollution, acid rain can significantly alter soil physicochemical and biochemical processes, but our knowledge of how acid rain affects soil enzyme activity is still limited. To quantify the overall magnitude and direction of the response of soil enzyme activity to acid rain, we conducted a linear mixed model–based meta-analysis of 40 articles. Our analysis revealed that acid rain decreased enzyme activity by an average of 4.87%. Soil dehydrogenase and protease activities were particularly sensitive to acid rain, with significant inhibitions observed. The effect of acid rain was moderated by acid rain intensity (i.e., H + addition rate, total H + added, and acid rain pH) and soil fraction (i.e., rhizosphere and bulk soil). Structural equation modelling further revealed that acid rain suppressed soil microbial biomass by acidifying the soil and that the reduction in microbial biomass directly led to the inhibition of enzyme activity in bulk soil. However, the enzyme activity in the rhizosphere soil was not affected by acid rain due to the rhizosphere effect, which was also not impacted by the decreased soil pH induced by acid rain in rhizosphere. Our study gives an insight into how bulk soil enzyme activity is impacted by acid rain and highlights the need to incorporate rhizosphere processes into acid rain-terrestrial ecosystem models.