Effects of fertilizer and biochar applications on the relationship among soil moisture, temperature, and N2O emissions in farmland
| Autor: | Peiling Yang, Lu Ping, Ren Shumei, Xiao Wang |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2021 |
| Předmět: |
Pollution
Fertigation N2O emissions Field experiment media_common.quotation_subject 010501 environmental sciences engineering.material 01 natural sciences General Biochemistry Genetics and Molecular Biology Human fertilization Biochar Sensitivity coefficient Soil temperature Water content 0105 earth and related environmental sciences media_common General Neuroscience 04 agricultural and veterinary sciences General Medicine Agronomy Fertilization Soil water 040103 agronomy & agriculture engineering 0401 agriculture forestry and fisheries Environmental science Medicine Fertilizer Soil moisture General Agricultural and Biological Sciences |
| Zdroj: | PeerJ, Vol 9, p e11674 (2021) |
| ISSN: | 2167-8359 |
| Popis: | Background Di-nitrogen oxide (N2O) emissions from soil may lead to nonpoint-source pollution in farmland. Improving the C and N content in the soil is an excellent strategy to reduce N2O emission and mitigate soil N loss. However, this method lacks a unified mathematical index or standard to evaluate its effect. Methods To quantify the impact of soil improvement (C and N) on N2O emissions, we conducted a 2-year field experiment using biochar as carbon source and fertilizer as nitrogen source, setting three treatments (fertilization (300 kg N ha−1), fertilization + biochar (30 t ha−1), control). Results Results indicate that after biochar application, the average soil water content above 20 cm increased by ∼26% and 26.92% in 2019, and ∼10% and 12.49% in 2020. The average soil temperature above 20 cm also increased by ∼2% and 3.41% in 2019. Fertigation significantly promotes the soil N2O emissions, and biochar application indeed inhibited the cumulation by approximately 52.4% in 2019 and 33.9% in 2020, respectively. N2O emissions strongly depend on the deep soil moisture and temperature (20–80 cm), in addition to the surface soil moisture and temperature (0–20 cm). Therefore, we established an exponential model between the soil moisture and N2O emissions based on theoretical analysis. We find that the N2O emissions exponentially increase with increasing soil moisture regardless of fertilization or biochar application. Furthermore, the coefficient a 2O emissions initially increase and then decrease. The aRU CK indicates that fertilization does promote the rate of N2O emissions, and the aBRU > aRU indicates that biochar application mitigates this rate induced by fertilization. This conclusion can be verified by the sensitivity coefficient (SCB of 1.02 and 14.74; SCU of 19.18 and 20.83). Thus, we believe the model can quantify the impact of soil C and N changes on N2O emissions. We can conclude that biochar does significantly reduce N2O emissions from farmland. |
| Databáze: | OpenAIRE |
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