Nan Shan , Shunzhe Wei , Yifan Fan , Yi Tong , Chuan Wang , Xiaoshan Hu , Bo Liu , Wenlin Wang , Nan Shan
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引用次数: 0
Abstract
Ammonia (NH3) is a key PM2.5 precursor that significantly contributes to haze formation and air quality degradation. Livestock farming accounts for more than 50 % of China's annual NH3 emissions, and large-scale pig farms represent a major anthropogenic source. However, the current systematic knowledge of NH3 emissions characteristics from large-scale pig farms is still deficient, and there are insufficient studies localized for China. We conducted year-round intensive monitoring of NH3 emissions from a representative large-scale pig farm in the Yangtze River Delta to quantify the interactions between growth stage and season. In terms of seasonal variation, NH3 emissions peaked in summer at 3.95 kg NH3·year−1·head−1 and were lowest in winter at 1.53 kg NH3·year−1·head−1. For the growth stages, we found that the average annual emission factors for piglet houses, nursery houses, fattening houses, gestation houses, and farrowing houses (with some piglets included) were 0.24, 0.84, 1.83, 3.55, and 5.61 kg NH3·year−1·head−1. In addition, this study found that temperature was the key driver of NH3 emissions (mean Spearman's r = 0.66, P < 0.001), whereas the overall correlation for humidity was weaker, with emissions significantly suppressed only in winter when ventilation was inadequate (average r = 0.49, P < 0.001). Based on local conditions, the farm-level annual NH3 emission factor was determined to be 2.45 kg NH3·year−1·head−1, highlighting the critical summer period for targeted mitigation. These findings provide a scientific basis for refining regional emission inventories and for developing stage- and season-specific abatement strategies that support PM2.5 control and the sustainable transformation of intensive pig production in the Yangtze River Delta.
氨(NH3)是PM2.5的关键前体,对雾霾的形成和空气质量的恶化起着重要作用。畜牧业占中国每年NH3排放量的50%以上,而大型养猪场是一个主要的人为来源。然而,目前对规模化养猪场NH3排放特征的系统认识仍然不足,针对中国的本土化研究也不足。本研究对长三角地区某具有代表性的大型养猪场进行了全年NH3排放的密集监测,以量化生长期与季节之间的相互作用。从季节变化来看,夏季NH3排放量最高,为3.95 kg NH3·年−1·水头−1,冬季最低,为1.53 kg NH3·年−1·水头−1。仔猪舍、苗圃舍、育肥舍、妊娠舍和产仔舍(含部分仔猪)的年平均排放因子分别为0.24、0.84、1.83、3.55和5.61 kg NH3·年−1·头−1。此外,本研究发现温度是NH3排放的关键驱动因素(平均Spearman’s r = 0.66, P <;0.001),而湿度的整体相关性较弱,只有在冬季通风不足时,排放才会受到显著抑制(平均r = 0.49, P <;0.001)。根据当地条件,确定农场级年NH3排放因子为2.45 kg NH3·年−1·头−1,突出了目标减排的关键夏季。这些发现为完善区域排放清单、制定阶段性和阶段性减排策略提供了科学依据,为长三角地区的PM2.5控制和集约化养猪业的可持续转型提供了支持。