Long-term nitrogen deposition does not exacerbate soil acidification in tropical broadleaf plantations. (8th November 2021)

• Record Type: Journal Article
• Authors: Huang, Juan; Zhang, Wei; Li, Yuelin; Wang, Senhao; Mao, Jinhua; Mo, Jiangming; Zheng, Mianhai
• Is Part Of: Environmental research letters. Volume 16:Number 11(2021)
• Publication Date: 2021-11-08
• Subjects: soil acidity -- nitrogen deposition -- long-term nitrogen addition -- nitrogen loss -- tropical plantation ecosystems; Environmental sciences -- Periodicals; Human ecology -- Research -- Periodicals; Environmental health -- Periodicals; 333.7
• DOI: 10.1088/1748-9326/ac30bd
• Languages: English
• ISSNs: 1748-9326

Abstract

Abstract: Nitrogen (N) deposition induces soil acidification in natural forests; however, whether it increases soil acidity in tropical plantations with simple tree structures compared with natural forests remains unclear. This study aimed to investigate the effects of N deposition on the soil acidity of tropical broadleaf plantations dominated by Acacia auriculiformis and Eucalyptus urophylla in South China, which has been enduring N deposition for over 30 years, and investigate the reasons for the changes in soil acidity. Long-term N addition did not affect soil acidity in the two plantations, with no significant changes in soil pH values, and exchangeable non-acidic and acidic cation concentrations. Long-term N deposition did not significantly affect the plant and total soil N concentrations, but significantly increased the soil nitrous oxide emission rates and total dissolved N concentrations in the soil solutions. Our findings indicate that most of the added N was lost via leaching and emissions, such that long-term N addition did not exacerbate soil acidification in broadleaf plantations, thereby providing novel insight into the effects of atmospheric N deposition on forest ecosystems. Overall, our study indicates that long-term N deposition does not always lead to soil acidification in tropical forests, as previously expected.