Effects of the three amendments on NH3 volatilization, N2O emissions, and nitrification at four salinity levels: An indoor experiment

Panpan Gao; Xianghui Yan; Xuejing Xia; Dan Liu; Songnian Guo; Ronghui Ma; Yanhong Lou; Zhongchen Yang; Hui Wang; Quangang Yang; Hong Pan; Yuping Zhuge

doi:10.1016/j.jenvman.2024.120399

Effects of the three amendments on NH₃ volatilization, N₂O emissions, and nitrification at four salinity levels: An indoor experiment

J Environ Manage. 2024 Mar:354:120399. doi: 10.1016/j.jenvman.2024.120399. Epub 2024 Feb 22.

Authors

Panpan Gao¹, Xianghui Yan¹, Xuejing Xia¹, Dan Liu¹, Songnian Guo¹, Ronghui Ma², Yanhong Lou¹, Zhongchen Yang¹, Hui Wang¹, Quangang Yang¹, Hong Pan³, Yuping Zhuge⁴

Affiliations

¹ National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Resources and Environment, Shandong Agricultural University, Daizong Road, Tai'an, 271018, China.
² Agricultural Technology Promotion Center of Shandong Province, Jinan, 252199, China.
³ National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Resources and Environment, Shandong Agricultural University, Daizong Road, Tai'an, 271018, China. Electronic address: panhong6239@163.com.
⁴ National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Resources and Environment, Shandong Agricultural University, Daizong Road, Tai'an, 271018, China. Electronic address: zhugeyp@sdau.edu.cn.

PMID: 38387357
DOI: 10.1016/j.jenvman.2024.120399

Abstract

The marked salinity and alkaline pH of coastal saline soil profoundly impact the nitrogen conversion process, leading to a significantly reduced nitrogen utilization efficiency and substantial gaseous nitrogen loss. The application of soil amendments (e.g. biochar, manure, and gypsum) was proved to be effective for the remediation of saline soils. However, the effects of the three amendments on soil nitrogen transformation in soils with various salinity levels, especially on NH₃ volatilization and N₂O emission, remain elusive. Here, we reported the effects of biochar, manure, and gypsum on NH₃ volatilization and N₂O emission under four natural salinity gradients in the Yellow River Delta. Also, high-throughput sequencing and qPCR analysis were performed to characterize the response of nitrification (amoA) and denitrification (nirS, nirK, and nosZ) functional genes to the three amendments. The results showed that the three amendments had little effect on NH₃ volatilization in low- and moderate-salinity soils, while biochar stimulated NH₃ volatilization in high-salinity soils and reduced NH₃ volatilization in severe-salinity soils. Spearman correlation analysis demonstrated that AOA was significantly and positively correlated with the NO₃^--N content (r = 0.137, P < 0.05) and N₂O emissions (r = 0.174, P < 0.01), which indicated that AOA dominated N₂O emissions from nitrification in saline soils. Structural equation modeling indicated that biochar, manure, and gypsum affected N₂O emission by influencing soil pH, conductivity, mineral nitrogen content, and functional genes (AOA-amoA and nosZ). Two-way ANOVA further showed that salinity and amendments (biochar, manure, and gypsum) had significant effects on N₂O emissions. In summary, this study provides valuable insights to better understand the effects of gaseous N changes in saline soils, thereby improving the accuracy and validity of future GHG emission predictions and modeling.

Keywords: Amendments nitrification; N(2)O; NH(3); Saline soil.

MeSH terms

Calcium Sulfate
Charcoal / chemistry
Denitrification*
Manure
Nitrification*
Nitrogen / analysis
Nitrous Oxide / analysis
Salinity
Soil / chemistry
Soil Microbiology
Volatilization

Substances

biochar
Nitrous Oxide
Calcium Sulfate
Manure
Charcoal
Soil
Nitrogen