Scholarlink

Purpose <p>Urea, one of the most commonly used nitrogen (N) fertilizers, is a major contributor to greenhouse gas (GHG) emissions from croplands. Coating urea with chars may reduce GHG emissions from urea; however, the effect of coating urea with chars on soil N availability and GHG emissions is not clear.</p> Methods <p>We tested the effect of coating urea with three types of chars (wheat straw biochar (SB), recovered carbon (C) black (RCB) and activated C (AC)) on soil N availability and GHG emissions in a 62-day incubation experiment. The treatments studied include no urea application (CK), and applications of uncoated urea (UCU), RCB-coated urea (RCBU), AC-coated urea (ACU), SB-coated urea (SBU), and a urease- and nitrification-inhibitor (Neon Surface, 17% N-(n-butyl) thiophosphoric triamide and 25% Dicyandiamide) coated urea (NSU).</p> Results <p>Ammonium N was higher in NSU than in the other treatments except in SBU at 10 days, while nitrate N was not different between coated and uncoated urea except in NSU at 10 days in the incubation. All urea treatments increased soil CO<sub>2</sub> and N<sub>2</sub>O emissions compared to the CK. The N<sub>2</sub>O emissions were reduced by 76.0% in NSU and 24.1% in SBU, but not in RCBU and ACU, compared to UCU, even though the application rate, and C/N ratio of the material coated on urea was much lower in SBU than in RCBU and ACU treatments. The reduction in N<sub>2</sub>O emission rates occurred between days 4 and 34 in NSU and between days 22 and 34 in SBU.</p> Conclusions <p>Coating urea with Neon Surface, SB, RCB and AC did not affect soil CO<sub>2</sub> emissions, while coating urea with Neon Surface and SB, rather than RCB and AC, reduced soil N<sub>2</sub>O emissions, suggesting that coating material needs to be carefully selected to effectively mitigate GHG emissions from fertilizer applications.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Wheat straw biochar-, recovered carbon black- and activated carbon-coated urea have divergent effects on soil N2O emissions

  • 期刊论文

  • 发表日期：

    2025年6月20日

查看全文
  • Tongqing Su,
  • Zhengfeng An,
  • Ken Greer,
  • Eric Bremer,
  • Scott X. Chang

摘要

Purpose

Urea, one of the most commonly used nitrogen (N) fertilizers, is a major contributor to greenhouse gas (GHG) emissions from croplands. Coating urea with chars may reduce GHG emissions from urea; however, the effect of coating urea with chars on soil N availability and GHG emissions is not clear.

Methods

We tested the effect of coating urea with three types of chars (wheat straw biochar (SB), recovered carbon (C) black (RCB) and activated C (AC)) on soil N availability and GHG emissions in a 62-day incubation experiment. The treatments studied include no urea application (CK), and applications of uncoated urea (UCU), RCB-coated urea (RCBU), AC-coated urea (ACU), SB-coated urea (SBU), and a urease- and nitrification-inhibitor (Neon Surface, 17% N-(n-butyl) thiophosphoric triamide and 25% Dicyandiamide) coated urea (NSU).

Results

Ammonium N was higher in NSU than in the other treatments except in SBU at 10 days, while nitrate N was not different between coated and uncoated urea except in NSU at 10 days in the incubation. All urea treatments increased soil CO2 and N2O emissions compared to the CK. The N2O emissions were reduced by 76.0% in NSU and 24.1% in SBU, but not in RCBU and ACU, compared to UCU, even though the application rate, and C/N ratio of the material coated on urea was much lower in SBU than in RCBU and ACU treatments. The reduction in N2O emission rates occurred between days 4 and 34 in NSU and between days 22 and 34 in SBU.

Conclusions

Coating urea with Neon Surface, SB, RCB and AC did not affect soil CO2 emissions, while coating urea with Neon Surface and SB, rather than RCB and AC, reduced soil N2O emissions, suggesting that coating material needs to be carefully selected to effectively mitigate GHG emissions from fertilizer applications.