상세정보
Export to Refworks부가기능
A Longitudinal, Landscape-Scale Field Study Assessing The Effects of Commercial Hog Operations on Microbial Quality of Surface Waters in North Carolina, Usa
상세 프로파일
| 자료유형 | 학위논문 |
|---|---|
| 서명/저자사항 | A Longitudinal, Landscape-Scale Field Study Assessing The Effects of Commercial Hog Operations on Microbial Quality of Surface Waters in North Carolina, Usa. |
| 개인저자 | Christenson, Elizabeth . |
| 단체저자명 | The University of North Carolina at Chapel Hill. Environmental Sciences and Engineering. |
| 발행사항 | [S.l.]: The University of North Carolina at Chapel Hill., 2019. |
| 발행사항 | Ann Arbor: ProQuest Dissertations & Theses, 2019. |
| 형태사항 | 218 p. |
| 기본자료 저록 | Dissertations Abstracts International 81-03B. Dissertation Abstract International |
| ISBN | 9781085760478 |
| 학위논문주기 | Thesis (Ph.D.)--The University of North Carolina at Chapel Hill, 2019. |
| 일반주기 |
Source: Dissertations Abstracts International, Volume: 81-03, Section: B.
Advisor: Stewart, Jill . |
| 이용제한사항 | This item must not be sold to any third party vendors. |
| 요약 | North Carolina is one of the leading states in the USA for swine production on commercial hog operations (CHOs). Swine manure from CHOs contains bacteria and antibiotic resistance elements (AREs) and there is concern that CHOs act as sources of fecal bacteria and AREs to surface water through precipitation-driven runoff or leaching. While research has found high concentrations of bacteria and AREs downstream of CHOs, this work did not adequately take into account other fecal sources. Additionally, few studies have appropriately controlled for background levels of resistance so that the effects of CHOs on dissemination of AREs in the environment is difficult to assess.A longitudinal, landscape-scale field study was designed to determine whether there were effects of CHOs on microbial water quality while addressing concerns of bias and confounding between observational groups. This work compared similar, small, agricultural watersheds with (n = 13) and without (n = 9) CHOs over one year and found higher measures of E. coli, swine-associated gene marker, pig-2-bac, and antibiotic resistant E. coli in watersheds with CHOs compared to those without. Resistance to highest priority antibiotics was only observed in sites with CHOs. A multiple linear model was constructed to determine whether higher concentrations of E. coli in sites with CHOs were a result of differences in environmental conditions or exposure to confounding fecal sources. Modeling showed that even when controlling for large effects from precipitation and effects from confounding fecal sources, CHOs contributed E. coli to surface water and had a larger effect compared to human and wildlife sources.Results suggest that microbial water quality is poorer with increasing CHO size and proximity to surface water and that some CHOs may act as sources for human pathogens and AREs in surface water. These results have implications for state and federal policy, suggesting a need to recognize and regulate the discharge from CHOs during dry and wet conditions through discharge permits and/or CHO-specific management plans. Mitigation strategies that should be considered include improvements to CHO manure and land management practices aimed to reduce loading of fecal bacteria to surface water and to limit bacterial transport. |
| 일반주제명 | Microbiology. Public health. Limnology. |
| 언어 | 영어 |
| 바로가기 | 
: 이 자료의 원문은 한국교육학술정보원에서 제공합니다. |
