Nartey, Obemah DavidLiu, DeyanUwamungu, Jean YvesLuo, JiafaLindsey, StuartDi, HongChen, ZengmingYuan, JunjiDing, Weixin2021-02-092021-01-142021-05-152020-12-200048-969733465630 (pubmed)https://hdl.handle.net/10182/13367Dairy farms produce considerable quantities of nutrient-rich effluent, which is generally stored before use as a soil amendment. Unfortunately, a portion of the dairy effluent N can be lost through volatilization during open pond storage to the atmosphere. Adding of covering materials to effluent during storage could increase contact with NH₄+ and modify effluent pH, thereby reducing NH₃ volatilization and retaining the effluent N as fertilizer for crop application. Here the mitigation effect of cover materials on ammonia (NH₃) volatilization from open stored effluents was measured. A pilot-scale study was conducted using effluent collected at the Youran Dairy Farm Company Limited, Luhe County, Jiangsu, China, from 15 June to 15 August 2019. The study included seven treatments: control without amendment (Control), 30-mm × 25-mm corn cob pieces (CC), light expanded clay aggregate - LECA (CP), lactic acid (LA) and lactic acid plus CC (CCL), CP (CPL) or 20-mm plastic balls (PBL). The NH₃ emission from the Control treatment was 120.1 g N m−2, which was increased by 38.1% in the CP treatment, possibly due to increased effluent pH. The application of CC reduced NH₃ loss by 69.2%, compared with the Control, possibly due to high physical resistance, adsorption of NH₄+ and effluent pH reduction. The lactic acid amendment alone and in combination with other materials also reduced NH₃ volatilization by 27.4% and 31.0–46.7%, respectively. After 62 days of storage, effluent N conserved in the CC and CCL treatments were 21.0% and 22.0% higher than that in the Control (P < 0.05). Our results suggest that application of corn cob pieces, alone or in combination with lactic acid, as effluent cover could effectively mitigate NH₃ volatilization and retain N, thereby enhancing the fertilizer value of the stored dairy effluent and co-applied as a soil amendment after two months open storage.10 pagesPrint-Electronicen© 2021 Elsevier B.V. All rights reserved.ammonia volatilizationcover materialseffluent N retainingeffluent storagemitigation practiceZea maysNitrogenAmmoniaSoilFertilizersVolatilizationAgricultureChinaNutrientsJournal Article10.1016/j.scitotenv.2020.144712ANZSRC::05 Environmental SciencesANZSRC::0701 Agriculture, Land and Farm ManagementANZSRC::0503 Soil Sciences1879-1026