Dolomite application to acidic soils: a promising option for mitigating N2O emissions

• Published in: Environmental science and pollution research international 2015-12, Vol.22 (24), p.19961-19970
• Main Authors: Shaaban, Muhammad, Peng, Qi-an, Hu, Ronggui, Wu, Yupeng, Lin, Shan, Zhao, Jinsong
• Format: Article
• Language: English
• Subjects: acid soils; Acidic soils; Acidification; Agricultural production; Air Pollutants - analysis; Air Pollution - prevention & control; ammonium nitrogen; Ammonium sulfate; Aquatic Pollution; Atmospheric Protection/Air Quality Control/Air Pollution; Calcium Carbonate - chemistry; Carbon; Carbon - analysis; Crop production; Denitrification; Dissolved organic carbon; Dolomite; Earth and Environmental Science; Ecotoxicology; Emissions; Environment; Environmental Chemistry; Environmental Health; Fertilizers; greenhouse gas emissions; Hydrogen-Ion Concentration; Laboratories; liming; Magnesium - chemistry; microbial biomass; Mineralization; nitrate nitrogen; Nitrates; Nitrogen; Nitrogen - analysis; Nitrogen - chemistry; nitrogen fertilizers; Nitrous oxide; Nitrous Oxide - analysis; Organic soils; Research Article; Soil - chemistry; Soil acidification; Soil amendment; Soil pH; Soil properties; Soil testing; Waste Water Technology; Water - chemistry; Water Management; Water Pollution Control
• ISSN: 0944-1344; 1614-7499
• DOI: 10.1007/s11356-015-5238-4

Soil acidification is one of the main problems to crop productivity as well as a potent source of atmospheric nitrous oxide (N₂O). Liming practice is usually performed for the amelioration of acidic soils, but the effects of dolomite application on N₂O emissions from acidic soils are still not well understood. Therefore, a laboratory study was conducted to examine N₂O emissions from an acidic soil following application of dolomite. Dolomite was applied to acidic soil in a factorial design under different levels of moisture and nitrogen (N) fertilizer. Treatments were as follows: dolomite was applied as 0, 1, and 2 g kg⁻¹ soil (named as CK, L, and H, respectively) under two levels of moisture [i.e., 55 and 90 % water-filled pore space (WFPS)]. All treatments of dolomite and moisture were further amended with 0 and 200 mg N kg⁻¹ soil as (NH₄)₂SO₄. Soil properties such as soil pH, mineral N (NH₄ ⁺-N and NO₃ ⁻-N), microbial biomass carbon (MBC), dissolved organic carbon (DOC), and soil N₂O emissions were analyzed throughout the study period. Application of N fertilizer rapidly increased soil N₂O emissions and peaked at 0.59 μg N₂O-N kg⁻¹ h⁻¹ under 90 % WFPS without dolomite application. The highest cumulative N₂O flux was 246.32 μg N₂O-N kg⁻¹ under 90 % WFPS without dolomite addition in fertilized soil. Addition of dolomite significantly (p ≤ 0.01) mitigated N₂O emissions as soil pH increased, and H treatment was more effective for mitigating N₂O emissions as compared to L treatment. The H treatment decreased the cumulative N₂O emissions by up to 73 and 67 % under 55 and 90 % WFPS, respectively, in fertilized soil, and 60 and 68 % under 55 and 90 % WFPS, respectively, in unfertilized soil when compared to those without dolomite addition. Results demonstrated that application of dolomite to acidic soils is a promising option for mitigating N₂O emissions.