College of Resources and Environmental Sciences, Hebei Agricultural University, Baoding 071000, PR China.
College of Resources and Environmental Sciences, Hebei Agricultural University, Baoding 071000, PR China; Key Laboratory for Farmland Eco-Environment of Hebei Province, Baoding 071000, PR China.
Sci Total Environ. 2021 Jun 1;771:145454. doi: 10.1016/j.scitotenv.2021.145454. Epub 2021 Jan 29.
Biochars have been used to reduce gas emissions from manure composting practices and to recover nutrients from wastewater because of their effective sorption capacity. However, relatively less is known about the impacts of different alkaline biochars on the gas emissions from liquid manure. Materials including two commercial biochars prepared from walnut shell (WA) and coconut shell (CC), respectively, and coal (CO) were applied (with manure/biochar ratio of 20:1 in weight) to examine their influence on NH, CH, and NO emissions from liquid pig manure during a 68-d period in comparison with a control (CK, without biochars), and to investigate the evolution of the manure N mass balances and the changes in biochar properties during liquid manure storage to understand the characteristics of biochar. Compared with the CK, the application of WA, CC, and CO biochars increased the NH emissions by 4.00, 3.87, and 1.23 times, respectively, the absorbed N content of the biochars was markedly lower than the enhanced gaseous losses through NH emissions. Similarly, the total greenhouse gas (GHG) emissions from the manure with WA, CC, and CO biochar application were 6.28, 5.55, and 0.83 times greater than those observed with the CK, respectively, and were mainly attributed to the enhanced CH emissions. The significant contribution (5%-12%) of indirect GHG emissions from the enhanced NH-N losses was also identified. The hypothesis for the enhanced gas emissions from liquid manure with biochar addition has been discussed in the present study; however, further investigation in the future is warranted.
生物炭因其有效吸附能力而被用于减少粪便堆肥过程中的气体排放并从废水中回收养分。然而，对于不同碱性生物炭对液态粪便气体排放的影响，人们知之甚少。本研究选用了两种商业生物炭（分别由核桃壳（WA）和椰子壳（CC）制备）和煤（CO）作为材料（以重量计，粪便/生物炭比为 20:1），与对照（CK，不添加生物炭）相比，考察了它们对液态猪粪中 NH、CH 和 NO 排放的影响，并研究了粪肥 N 质量平衡的演变和液态粪肥储存过程中生物炭特性的变化，以了解生物炭的特性。与 CK 相比，WA、CC 和 CO 生物炭的应用分别使 NH 排放增加了 4.00、3.87 和 1.23 倍，生物炭的吸附 N 含量明显低于 NH 排放引起的气态损失增加。同样，添加 WA、CC 和 CO 生物炭的粪肥总温室气体（GHG）排放量分别比 CK 增加了 6.28、5.55 和 0.83 倍，主要归因于 CH 排放的增加。还确定了增强的 NH-N 损失间接 GHG 排放的显著贡献（5%-12%）。本文讨论了添加生物炭对液态粪肥中增强气体排放的假设，但未来需要进一步研究。
