Park Sang Hyun, Lee Bok Rye, Kim Tae Hwan
Department of Animal Science, College of Agriculture & Life Science, Chonnam National University, Gwangju 61186, Korea.
Biotechnology Research Institute, Chonnam National University, Gwangju 61186, Korea.
Anim Biosci. 2021 Dec;34(12):2023-2033. doi: 10.5713/ab.21.0046. Epub 2021 Apr 23.
The present study was conducted to assess the effect of urease inhibitor (hydroquinone [HQ]) and nitrification inhibitor (dicyandiamide [DCD]) on nitrogen (N) use efficiency of pig slurry for perennial ryegrass regrowth yield and its environmental impacts.
A micro-plot experiment was conducted using pig slurry-urea 15N treated with HQ and/or DCD and applied at a rate of 200 kg N/ha. The flows of N derived from the pig slurry urea to herbage regrowth and soils as well as soil N mineralization were estimated by tracing pig slurry-urea 15N, and the N losses via ammonia (NH3), nitrous oxide (N2O) emission, and nitrate (NO3-) leaching were quantified for a 56 d regrowth of perennial ryegrass (Lolium perenne) sward.
Herbage dry matter at the final regrowth at 56 d was significantly higher in the HQ and/or DCD applied plots, with a 24.5% to 42.2% increase in 15N recovery by herbage compared with the control. Significant increases in soil 15N recovery were also observed in the plots applied with the inhibitors, accompanied by the increased N content converted to soil inorganic N (NH4+ +NO3-) (17.3% to 28.8% higher than that of the control). The estimated loss, which was not accounted for in the herbage-soil system, was lower in the plots applied with the inhibitors (25.6% on average) than that of control (38.0%). Positive effects of urease and/or nitrification inhibitors on reducing N losses to the environment were observed at the final regrowth (56 d), at which cumulative NH3 emission was reduced by 26.8% (on average 3 inhibitor treatments), N2O emission by 50.2% and NO3- leaching by 10.6% compared to those of the control.
The proper application of urease and nitrification inhibitors would be an efficient strategy to improve the N use efficiency of pig slurry while mitigating hazardous environmental impacts.
本研究旨在评估脲酶抑制剂（对苯二酚[HQ]）和硝化抑制剂（双氰胺[DCD]）对猪粪中氮（N）用于多年生黑麦草再生产量的利用效率及其环境影响。
进行了一项微区试验，使用经HQ和/或DCD处理的猪粪尿素，施用量为200 kg N/公顷。通过追踪猪粪尿素15N来估算猪粪尿素中氮向牧草再生和土壤的流动以及土壤氮矿化，并且对多年生黑麦草（Lolium perenne）草皮56天再生期内通过氨（NH3）、氧化亚氮（N2O）排放和硝酸盐（NO3-）淋失造成的氮损失进行了量化。
在施用HQ和/或DCD的小区中，56天最终再生时的牧草干物质显著更高，与对照相比，牧草对15N的回收率提高了24.5%至四十二点二%。在施用抑制剂的小区中，土壤对15N的回收率也显著提高，同时转化为土壤无机氮（NH4+ +NO3-）的氮含量增加（比对照高17.3%至28.8%）。在施用抑制剂的小区中，未计入牧草 - 土壤系统的估计损失较低（平均为25.6%），低于对照（38.0%）。在最终再生（56天）时，观察到脲酶和/或硝化抑制剂对减少向环境中氮损失的积极作用，与对照相比，此时累积NH3排放量减少了26.8%（3种抑制剂处理平均），N2O排放量减少了50.2%，NO3-淋失减少了10.6%。
合理施用脲酶和硝化抑制剂将是提高猪粪氮利用效率同时减轻有害环境影响的有效策略。
