In order to minimise nutrient losses, comprehensive overviews of the magnitude of gaseous emissions from manure composting processes and the factors that influence these losses are urgently needed. This study presents a meta-analysis of greenhouse gases (GHGs) and ammonia (NH3) emissions from four main dairy manure composting methods (static, turning, windrow and silo) based on 41 scientific articles (153 treatments). Gaseous emissions and secondary variables such as average composting temperature, initial moisture content, initial total carbon (TC) and initial total nitrogen (TN) content from each compost treatment were extracted and normalised to enable inter-study comparison. Six mitigation measures for composting were selected and mitigation efficiency ( E m ) of each measure on different gas emissions were calculated. Gaseous emissions from different composting methods showed large differences. Turning composting resulted in larger carbon and nitrogen losses compared to other composting methods. Although silo composting significantly promoted NH3 emission, it reduced GHG losses by 82.84% compared with turning composting. Principal component analysis showed that the initial TC and TN content of the composted material were crucial in mediating gaseous emissions. Low TC and TN content can simultaneously reduce CH4, CO2 and N2O emissions. Applying compost biofilters was the most effective way to reduce NH3 emission with ME value of −97%. Adding sawdust or straw could reduce CH4 and N2O emissions by 66.3% and 44.0% respectively. Gaseous emissions from dairy manure composting varied a lot and were affected by physical characteristics of composted material and management practices of composting.

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牛粪堆肥温室气体和氨排放的Meta分析

为了最大限度地减少养分损失，迫切需要对粪便堆肥过程中气体排放量的大小以及影响这些损失的因素进行全面概述。本研究基于 41 篇科学文章（153 种处理方法），对四种主要的乳制品粪便堆肥方法（静态、翻转、堆肥和筒仓）的温室气体 (GHG) 和氨 (NH3) 排放进行了荟萃分析。从每个堆肥处理中提取气体排放和次要变量，例如平均堆肥温度、初始水分含量、初始总碳 (TC) 和初始总氮 (TN) 含量，并对其进行标准化，以便进行研究间比较。选择了六种堆肥减缓措施，计算了每种措施对不同气体排放的减缓效率（E m ）。来自不同堆肥方法的气体排放表现出很大差异。与其他堆肥方法相比，轮转堆肥会导致更大的碳和氮损失。虽然筒仓堆肥显着促进了 NH3 排放，但与转向堆肥相比，它减少了 82.84% 的温室气体损失。主成分分析表明，堆肥材料的初始 TC 和 TN 含量对调节气体排放至关重要。低 TC 和 TN 含量可以同时减少 CH4、CO2 和 N2O 的排放。应用堆肥生物过滤器是减少 NH3 排放的最有效方法，ME 值为 -97%。添加木屑或秸秆可分别减少 CH4 和 N2O 排放 66.3% 和 44.0%。