Soil type regulates carbon and nitrogen stoichiometry and mineralization following biochar or nitrogen addition

Huanhuan Wang; Tianbao Ren; Karin Müller; Lukas Van Zwieten; Hailong Wang; Huilin Feng; Chensheng Xu; Fei Yun; Xiaoming Ji; Quanyu Yin; Hongzhi Shi; Guoshun Liu

doi:10.1016/j.scitotenv.2020.141645

Soil type regulates carbon and nitrogen stoichiometry and mineralization following biochar or nitrogen addition

Sci Total Environ. 2021 Jan 20:753:141645. doi: 10.1016/j.scitotenv.2020.141645. Epub 2020 Aug 16.

Authors

Huanhuan Wang¹, Tianbao Ren², Karin Müller³, Lukas Van Zwieten⁴, Hailong Wang⁵, Huilin Feng⁶, Chensheng Xu⁷, Fei Yun¹, Xiaoming Ji¹, Quanyu Yin¹, Hongzhi Shi⁶, Guoshun Liu⁸

Affiliations

¹ Henan Agricultural University, Zhengzhou 450002, China; Henan Biochar Engineering Technology Research Center, 450002, China.
² Henan Agricultural University, Zhengzhou 450002, China; Henan Biochar Engineering Technology Research Center, 450002, China; Henan Biochar Technology Engineering Laboratory, 450002, China. Electronic address: biochar2018@henau.edu.cn.
³ Plant & Food Research, Ruakura Research Centre, Hamilton 3240, New Zealand.
⁴ NSW Department of Primary Industries, Wollongbar, NSW 2477, Australia; Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China.
⁵ Biochar Engineering Technology Research Center of Guangdong Province, School of Environmental and Chemical Engineering, Foshan University, Foshan, Guangdong 528000, China; Key Laboratory of Soil Contamination Bioremediation of Zhejiang Province, Zhejiang A&F University, Hangzhou, Zhejiang 311300, China.
⁶ Henan Agricultural University, Zhengzhou 450002, China.
⁷ Nanping Branch, Fujian Tobacco Sciences Research Institute, Nanping 353000, China.
⁸ Henan Agricultural University, Zhengzhou 450002, China; Henan Biochar Engineering Technology Research Center, 450002, China; Henan Biochar Technology Engineering Laboratory, 450002, China.

PMID: 33207475
DOI: 10.1016/j.scitotenv.2020.141645

Abstract

Most studies on the effects of biochar and fertilizer on soil carbon (C) and nitrogen (N) mineralization, and microbial C and N content, are restricted to a single soil type, limiting our understanding of the interactions between these factors and microbial functions. To address this paucity in knowledge, we undertook a 3-year experiment using four contrasting soils to assess the role of peanut shell biochar and fertilizer on C and N mineralization, microbial C and N, and N stoichiometry. Across all four soils, biochar significantly (P < 0.05) increased soil carbon mineralization (C_min) and nitrogen mineralization (N_min) over three years compared to fertilizer and the control. Biochar also increased total C (C_soil) across the four soils in year 1, with the Fluvisol recording greater total C in year 2 and Phaeozem having greater total C in year 3. Biochar resulted in a higher microbial biomass C (C_mic), total N (N_soil) and microbial biomass N (N_mic); the degree of change was closely related to C_soil and N_soil. There was a positive correlation between C_mic:N_mic and C_soil:N_soil; while C_soil and C_mic increased following amendment with biochar, which reduced the soil C and N stoichiometric imbalance (N_imb) caused by the increase in the C to N ratio. However, fertilizer exacerbated the imbalance of soil C and N stoichiometry. Fertilizer also reduced the C_soil:N_soil and C_mic:N_mic ratios. Soil pH had a positive correlation with C_soil, C_mic, N_mic, C_min, N_min, C_soil:N_soil, C_mic:N_mic, and biochar increases this correlation. The soil pH was negatively correlated with C_imb:N_imb and N_soil. Fertilizer was positively correlated C_imb:N_imb and N_soil. In contrast, fertilizer N application lowered microbial biomass C:N. We conclude that biochar reduces the imbalance of soil C and N stoichiometry, whereas fertilizer increased this imbalance. Biochar had a greater impact on C and N in soils with a lower pH.

Keywords: Carbon to nitrogen ratio; Microbial biomass carbon; Microbial biomass nitrogen; Mineralization rate; Nutrient balance.

MeSH terms

Biomass
Carbon*
Charcoal
Fertilizers
Nitrogen* / analysis
Soil
Soil Microbiology

Substances

Fertilizers
Soil
biochar
Charcoal
Carbon
Nitrogen