Do Long-term Best Management Practices Influence Microbial Diversity and Antibiotic Resistant Genes In Water Runoff?

There is a global concern that antimicrobial resistant (AMR) genes may be transmitted through the food chain from animal manures to soil to surface water. Details are lacking on the ecology of AMR genes and bacteria in water systems, as well as how conservation management practices may minimize the movement of AMR genes. The aim of this study was to enumerate AMR genes and identify microbial diversity in water runoff following 14-years of poultry litter and cattle manure deposition and evaluate if pasture management [hayed (H), continuously grazed (CG), rotationally grazed (R), rotationally grazed with a buffer strip (RB), rotationally grazed with a fenced riparian buffer (RBR), and a control represented by nearby pristine water samples from a wild and scenic river)] minimized the presence and amount of AMR genes.

全球学界普遍担忧，抗菌药物耐药基因（antimicrobial resistant, AMR）可通过食物链，经动物粪便、土壤最终传播至地表水。目前针对水系统中抗菌药物耐药基因与细菌的生态特征，以及保护性管理措施如何抑制抗菌药物耐药基因扩散的相关研究细节仍较为匮乏。本研究的目标为：对经过14年家禽垫料与牛粪沉积后的径流水中的抗菌药物耐药基因进行定量分析，并鉴定其中的微生物多样性；同时评估不同牧场管理模式——包括刈割牧场（H）、连续放牧牧场（CG）、轮牧牧场（R）、带缓冲带的轮牧牧场（RB）、带围栏河岸缓冲带的轮牧牧场（RBR），以及以取自野生风景河流的邻近原始水样作为对照组——是否能够降低抗菌药物耐药基因的存在量与丰度。