Effects of Biochar and Its Fractions on Soil Nitrogen Forms and Microbial Communities Under Freeze-Thaw Conditions
Abstract
1. Introduction
2. Materials and Methods
2.1. Soil Sample
2.2. Extraction of Biochar Fractions
2.3. Experimental Design
2.4. Soil Indexes Determination Methods
2.4.1. Soil Environmental Factors Determination Methods
2.4.2. High-Throughput Sequencing of Soil Microbial Communities
2.5. Statistical Analysis
3. Results
3.1. Changes in Soil Characteristics
3.2. Changes in Soil Nitrogen
3.3. Changes in Soil Bacterial Communities
4. Discussion
4.1. The Effects of Biochar Fractions and Freeze-Thaw Cycles on Soil Characteristics
4.2. The Effect of Biochar Fractions and Freeze-Thaw on Soil Nitrogen
4.3. Effects of Biochar Fractions and Freeze-Thaw Cycles on Soil Microorganisms
5. Conclusions
Supplementary Materials
Author Contributions
Funding
Data Availability Statement
Acknowledgments
Conflicts of Interest
Abbreviations
FTCs | Freeze-thaw cycles |
FTN | Freeze-thaw cycle number |
N | Nitrogen |
PBC | Pristine biochar |
DBC | Dissolved fraction of biochar |
UBC | Undissolved fraction of biochar |
CTS | Constant temperature control soil |
FTS | Freeze-thaw control soil |
S + PBC | Soil with PBC treatment |
S + DBC | Soil with DBC treatment |
S + UBC | Soil with UBC treatment |
EC | Electrical conductivity |
NH4+-N | Ammonium nitrogen |
NO3--N | Nitrate nitrogen |
MBN | Microbial biomass nitrogen |
SOC | Soil total organic carbon |
AP | Available phosphorus |
AK | Rapidly-available potassium |
DOC | Dissolved organic carbon |
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Item | Value | Item | Value |
---|---|---|---|
pH | 6.35 | Available P (mg·kg−1) | 48.92 |
Electrical conductivity (μS·cm−1) | 162.3 | Rapidly available K (mg·kg−1) | 141.38 |
Organic matter (g·kg−1) | 46.74 | Sand (%) | 16.92 |
Organic C (g·kg−1) | 27.11 | Silt (%) | 58.23 |
Total N (g·kg−1) | 1.68 | Clay (%) | 24.87 |
Total P (g·kg−1) | 0.57 | Texture (USDA) | Silt Loam |
NH4+-N (mg·kg−1) | 17.19 | Bulk density (g·cm−3) | 1.35 |
NO3−-N (mg·kg−1) | 26.67 | Water holding capacity (%) | 36.50 |
Name | pH | EC (μS·cm−1) | Organic C | Total N | Total P | Total K |
---|---|---|---|---|---|---|
Pristine biochar (PBC) | 9.12 | 2690 | 37.99% | 0.64% | 0.19% | 2.70% |
Undissolved biochar fraction (UBC) | 9.37 | 265 | 43.23% | 0.69% | 0.12% | 1.44% |
Dissolved biochar fraction (DBC) | 8.97 | 2760 | 86.77 mg·L−1 | 1.43 mg·L−1 | 3.17 mg·L−1 | 571.6 mg·L−1 |
Factor | NH4+-N | NO3−-N | Inorganic N | MBN | Total N | |||||
---|---|---|---|---|---|---|---|---|---|---|
F | p | F | p | F | p | F | p | F | p | |
FTN | 13.46 | <0.01 | 62.01 | <0.01 | 23.35 | <0.01 | 164.19 | <0.01 | 1.13 | ns |
T | 214.30 | <0.01 | 63.64 | <0.01 | 170.33 | <0.01 | 45.73 | <0.01 | 18.83 | <0.01 |
T×TN | 1.17 | ns | 0.69 | ns | 0.55 | ns | 3.62 | <0.01 | 0.28 | ns |
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Gao, X.; Wang, Y.; Li, M.; Yu, J.; Han, S. Effects of Biochar and Its Fractions on Soil Nitrogen Forms and Microbial Communities Under Freeze-Thaw Conditions. Agronomy 2025, 15, 2437. https://doi.org/10.3390/agronomy15102437
Gao X, Wang Y, Li M, Yu J, Han S. Effects of Biochar and Its Fractions on Soil Nitrogen Forms and Microbial Communities Under Freeze-Thaw Conditions. Agronomy. 2025; 15(10):2437. https://doi.org/10.3390/agronomy15102437
Chicago/Turabian StyleGao, Xiaoyuan, Yunfei Wang, Ming Li, Jie Yu, and Song Han. 2025. "Effects of Biochar and Its Fractions on Soil Nitrogen Forms and Microbial Communities Under Freeze-Thaw Conditions" Agronomy 15, no. 10: 2437. https://doi.org/10.3390/agronomy15102437
APA StyleGao, X., Wang, Y., Li, M., Yu, J., & Han, S. (2025). Effects of Biochar and Its Fractions on Soil Nitrogen Forms and Microbial Communities Under Freeze-Thaw Conditions. Agronomy, 15(10), 2437. https://doi.org/10.3390/agronomy15102437