Divergent Accumulation of Microbial Residues and Amino Sugars in Loess Soil after Six Years of Different Inorganic Nitrogen Enrichment Scenarios
Abstract
:1. Introduction
2. Materials and Methods
2.1. Site and Treatment Description
2.2. Soil Sampling and Analysis
2.3. Microbial Residues and Amino Sugars Analysis
2.4. Aboveground Plant Biomass Determination
2.5. Data Analysis
3. Results
3.1. Effects of Chronic Nitrogen Enrichment on Amino Sugar and Microbial Residue Components from 2014 to 2018
3.2. Effects of Chronic Nitrogen Enrichment on Microbial Biomass, and Dissolved Organic Carbon and Nitrogen Concentrations in the Soil from 2014 to 2018
3.3. Relationships between Microbial Residues, Amino Sugars, and the Biochemical Properties of the Soil
4. Discussion
4.1. Effects of Chronic Nitrogen Enrichment on Microbial Residues and Amino Sugar Accumulation
4.2. Effects of Chronic Nitrogen Enrichment on Soil Biochemical Properties
5. Conclusions
Author Contributions
Funding
Institutional Review Board Statement
Informed Consent Statement
Data Availability Statement
Acknowledgments
Conflicts of Interest
References
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Properties | SOC (g kg−1) | TN (g kg−1) | NH4+-N (mg kg−1) | NO3−-N (mg kg−1) | Olsan—P (mg kg−1) | pH (1:2.5) | GluN (mg kg−1) | GalN (g kg−1) | MurN (g kg−1) |
---|---|---|---|---|---|---|---|---|---|
Content | 8.63 | 0.95 | 0.78 | 4.74 | 42.70 | 8.22 | 145.09 | 67.42 | 7.31 |
Parameter | Treatment | 2014 | 2015 | 2016 | 2017 | 2018 |
---|---|---|---|---|---|---|
GluN/GalN | No-N | 2.21 ± 0.01 a | 2.19 ± 0.04 a | 2.21 ± 0.04 a | 2.17 ± 0.06 a | 2.16 ± 0.05 a |
Low-N | 2.20 ± 0.08 a | 2.20 ± 0.07 a | 2.11 ± 0.10 a | 2.06 ± 0.08 a | 2.05 ± 0.03 a | |
Medium-N | 2.25 ± 0.03 a | 2.19 ± 0.05 a | 2.09 ± 0.08 a | 1.99 ± 0.05 b | 2.03 ± 0.02 b | |
High-N | 2.25 ± 0.04 a | 2.20 ± 0.06 a | 2.08 ± 0.06 a | 1.99 ± 0.04 b | 2.00 ± 0.07 b | |
GluN/MurN | No-N | 20.18 ± 0.24 a | 19.74 ± 0.38 a | 19.57 ± 0.17 a | 19.68 ± 1.22 a | 19.59 ± 0.41 a |
Low-N | 20.07 ± 0.44 a | 19.52 ± 0.21 a | 19.55 ± 0.93 a | 19.68 ± 0.51 ab | 19.52 ± 0.54 a | |
Medium-N | 20.79 ± 0.48 a | 19.34 ± 0.50 a | 19.61 ± 0.60 a | 19.03 ± 0.63 ab | 19.09 ± 0.83 a | |
High-N | 20.66 ± 0.39 a | 19.40 ± 0.18 a | 19.24 ± 0.42 a | 18.57 ± 0.48 b | 18.38 ± 0.37 b | |
Soil organic carbon (g kg−1) | No-N | 8.63 ± 0.13 a | 8.69 ± 0.11 a | 8.73 ± 0.34 b | 8.74 ± 0.13 b | 8.76 ± 0.30 b |
Low-N | 8.69 ± 0.37 a | 8.76 ± 0.06 a | 8.85 ± 0.18 ab | 8.93 ± 0.19 ab | 9.05 ± 0.23 ab | |
Medium-N | 8.69 ± 0.01 a | 8.88 ± 0.31 a | 8.97 ± 0.25 ab | 9.18 ± 0.07 ab | 9.39 ± 0.21 a | |
High-N | 8.64 ± 0.11 a | 8.95 ± 0.08 a | 9.08 ± 0.54 a | 9.24 ± 0.50 a | 9.51 ± 0.06 a | |
No-N | 8.31 ± 0.02a | 8.29 ± 0.02 a | 8.26 ± 0.01 b | 8.23 ± 0.01 a | 8.20 ± 0.01 a | |
Soil pH | Low-N | 8.31 ± 0.02 a | 8.27 ± 0.02 a | 8.23 ± 0.01 ab | 8.21 ± 0.01 a | 8.15 ± 0.01 ab |
Medium-N | 8.30 ± 0.02 a | 8.24 ± 0.02 a | 8.18 ± 0.01 ab | 8.15 ± 0.02 ab | 8.06 ± 0.03 bc | |
High-N | 8.30 ± 0.01 a | 8.22 ± 0.01 a | 8.15 ± 0.01 a | 8.10 ± 0.02 b | 8.01 ± 0.02 c |
Parameter | Treatment | 2014 | 2015 | 2016 | 2017 | 2018 |
---|---|---|---|---|---|---|
Total nitrogen (g kg−1) | No-N | 0.95 ± 0.02 a | 0.95 ± 0.03 a | 0.96 ± 0.06 b | 0.98 ± 0.04 c | 1.01 ± 0.11 c |
Low-N | 0.96 ± 0.01 a | 0.98 ± 0.04 a | 0.99 ± 0.03 b | 1.06 ± 0.09 b | 1.11 ± 0.05 b | |
Medium-N | 0.98 ± 0.01 a | 1.00 ± 0.02 a | 1.08 ± 0.16 a | 1.14 ± 0.07 a | 1.23 ± 0.03 a | |
High-N | 0.99 ± 0.03 a | 1.03 ± 0.04 a | 1.11 ± 0.07 a | 1.19 ± 0.04 a | 1.28 ± 0.01 a | |
Ammonium (mg kg−1) | No-N | 0.78 ± 0.01 b | 0.78 ± 0.01 b | 0.76 ± 0.02 c | 0.77 ± 0.01 c | 0.77 ± 0.03 c |
Low-N | 0.78 ± 0.02 b | 0.80 ± 0.01 b | 0.84 ± 0.02 b | 0.86 ± 0.02 b | 0.88 ± 0.01 b | |
Medium-N | 0.87 ± 0.02 a | 0.96 ± 0.02 a | 1.10 ± 0.01 a | 1.17 ± 0.03 a | 1.20 ± 0.03 a | |
High-N | 0.91 ± 0.01 a | 1.03 ± 0.02 a | 1.16 ± 0.02 a | 1.23 ± 0.02 a | 1.25 ± 0.01 a | |
Nitrate (mg kg−1) | No-N | 4.73 ± 0.14 c | 4.74 ± 0.11 c | 4.68 ± 0.02 c | 4.71 ± 0.22 d | 4.70 ± 0.09 d |
Low-N | 4.73 ± 0.11 c | 4.76 ± 0.13 c | 5.06 ± 0.09 c | 7.70 ± 0.14 c | 7.92 ± 0.16 c | |
Medium-N | 5.07 ± 0.07 b | 7.89 ± 0.07 b | 9.98 ± 0.11 b | 12.45 ± 0.23 b | 12.99 ± 0.33 b | |
High-N | 6.05 ± 0.12 a | 9.21 ± 0.29 a | 13.85 ± 0.36 a | 17.51 ± 0.47 a | 19.18 ± 0.35 a |
Parameter | pH | MBC | MBN | APB | DOC | SOC |
---|---|---|---|---|---|---|
GalN | −0.937 | 0.959 * | 0.934 * | 0.913 | 0.953 * | 0.933 * |
GluN | −0.967 * | 0.994 ** | 0.976 * | 0.956 * | 0.980 * | 0.983 * |
MurN | −0.996 ** | 0.993 ** | 0.995 ** | 0.989 * | 0.998 ** | 0.988 ** |
TAS | −0.963 * | 0.987 * | 0.967 * | 0.948 | 0.976 * | 0.971 * |
BR | −0.996 ** | 0.994 ** | 0.995 ** | 0.989 * | 0.994 ** | 0.989 ** |
FR | −0.939 | 0.962 * | 0.936 | 0.915 | 0.954 * | 0.937 * |
TMR | −0.974 * | 0.996 ** | 0.981 * | 0.964 * | 0.985 * | 0.985 * |
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Anning, D.K.; Li, Z.; Qiu, H.; Deng, D.; Zhang, C.; Ghanney, P.; Shen, Q. Divergent Accumulation of Microbial Residues and Amino Sugars in Loess Soil after Six Years of Different Inorganic Nitrogen Enrichment Scenarios. Appl. Sci. 2021, 11, 5788. https://doi.org/10.3390/app11135788
Anning DK, Li Z, Qiu H, Deng D, Zhang C, Ghanney P, Shen Q. Divergent Accumulation of Microbial Residues and Amino Sugars in Loess Soil after Six Years of Different Inorganic Nitrogen Enrichment Scenarios. Applied Sciences. 2021; 11(13):5788. https://doi.org/10.3390/app11135788
Chicago/Turabian StyleAnning, Dominic Kwadwo, Zhilong Li, Huizhen Qiu, Delei Deng, Chunhong Zhang, Philip Ghanney, and Qirong Shen. 2021. "Divergent Accumulation of Microbial Residues and Amino Sugars in Loess Soil after Six Years of Different Inorganic Nitrogen Enrichment Scenarios" Applied Sciences 11, no. 13: 5788. https://doi.org/10.3390/app11135788
APA StyleAnning, D. K., Li, Z., Qiu, H., Deng, D., Zhang, C., Ghanney, P., & Shen, Q. (2021). Divergent Accumulation of Microbial Residues and Amino Sugars in Loess Soil after Six Years of Different Inorganic Nitrogen Enrichment Scenarios. Applied Sciences, 11(13), 5788. https://doi.org/10.3390/app11135788