摘要
      家庭畜禽养殖场缺乏污染物处理系统，导致大量未经处理的粪便和尿液直接排放到环境中。兽医抗生素（VA）和重金属（HM）在农村环境中暴露的风险需要进一步研究。在本次调查中，从41个畜禽养殖场（猪、菊苣和牛）采集了221个样本（饲料、粪便、表层土壤、土壤剖面、水和植物）。在样品中经常检测到铜（Cu）、锌（Zn）、土霉素（OTC）和恩诺沙星（ENR）。砂壤土中的金属和VA比壤土中的更倾向于向深层迁移。污染土壤中的铜和锌主要以有效形式存在，这有利于它们向深层迁移。在这项研究中，还观察到OTC比ENR更容易迁移到更深的土层，因为它的pKa值相对较高。在80厘米深的土壤中出现了18个抗生素抗性基因（ARGs）和5个金属抗性基因（MRGs）以及一个可移动遗传元件（MGE）。在不同地点的土壤样本中检测到的优势属为卢氏杆菌属、梭状芽孢杆菌属和红肠杆菌属，这可能会增加ARGs的迁移或VA的降解。一项生态风险评估表明，VA对小麦、黄瓜和Brassiaca chinensis L的生长构成威胁。应紧急开发包括生物炭/改性生物炭、厌氧消化和粪肥堆肥在内的补救技术，以应对HM和VA的联合污染。
Abstract
The lack of treatment systems for pollutants in family-livestock and poultry sites results in large amounts of untreated manure and urine being directly discharged to environment. The risks from veterinary antibiotic (VA) and heavy metal (HM) exposure in the rural environment require further research. In this investigation, 221 samples (feed, manure, surface soil, soil profiles, water, and plant) were collected from 41 livestock and poultry farms (swine, chichen, and cattle). Copper (Cu), zinc (Zn), oxytetracycline (OTC), and enrofloxacin (ENR) were frequently detected in the samples. Metals and VAs in sandy loam soils were more inclined to migrate to deep layers than those in loam soils. Copper and Zn in the polluted soils mainly existed in available forms, which facilitated their migration to deep soil layers. In this study, OTC was also observed to migrate more easily to deeper soil layers than ENR due to its relatively high pKa value. Eighteen antibiotic resistance genes (ARGs) and 5 metal resistance genes (MRGs) along with one mobile genetic element (MGE) occurred in the soils at 80 cm depth. Luteimonas, Clostridium_sensu_stricto_1, and Rhodanobacter were dominant genera detected in the soil samples from different sites, which might increase migration of ARGs or degradation of VAs. An ecological risk assessment suggested that VAs posed threats to the growth of Triticum aestivum L, Cucumis sativus L, and Brassiaca chinensis L. Remediation techniques including biochar/modified biochar, anaerobic digestion, and manure composting should be developed urgently for joint HM and VA pollution.

https://www.sciencedirect.com/science/article/abs/pii/S0301479722008933