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181.
182.
长期施用猪粪水稻土抗生素抗性基因污染研究 总被引:15,自引:11,他引:4
为了全面研究猪粪有机肥对水稻土抗生素抗性及分布格局的影响,选择295对抗生素抗性基因引物,采用高通量荧光定量PCR对水稻土中的抗生素抗性基因污染情况进行了研究.结果表明,未施用猪粪水稻土检测出66种抗性基因,而施用猪粪水稻土则检测出107种抗生素抗性基因,施用猪粪后水稻土中抗生素抗性基因种类显著增加(P<0.05).相对于未施用猪粪水稻土,施用猪粪水稻土有49种抗生素抗性基因丰度显著增加(P<0.05),其中施用猪粪水稻土中喹诺酮类/氯霉素类抗性基因的mexF的丰度相对于未施用猪粪水稻土增加1791倍.高通量定量结果表明,施用猪粪的水稻土抗生素抗性基因分布格局发生显著变化,高通量定量技术是研究环境抗生素抗性基因的一个非常实用的工具. 相似文献
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Anthony M. Rizzuti Arthur D. Cohen Patrick G. Hunt Matias B. Vanotti 《Journal of environmental science and health. Part. B》2013,48(4):709-748
Abstract This paper reports on research designed to investigate the capacities of different highly characterized peats to remove odorous compounds from liquid swine manure (LSM). Peat types representing a wide range of properties were tested in order to establish which chemical and physical properties might be most indicative of their capacities to remediate odors produced by LSM. Eight percent slurries (of peat/LSM) were measured for odor changes after 24 hours using odor panel and GC/MS‐Solid‐phase microextraction (GC/MS‐SPME) analysis. The GC/MS‐SPME and odor panel results indicated that, although all peats tested in this study were found to be effective at removing odor‐causing compounds found in LSM, some peats tended to work better than others. Overall, the peats that were the most effective at removing odor‐causing compounds tended to have lower bulk densities, ash contents, fulvic acids contents, and guaiacyl lignins contents,and higher water holding capacities, hydraulic conductivities, “total other lignins”; contents, hydrogen contents, carbon contents, and total cellulose contents. GC/MS‐SPME analysis was found to be a reasonably inexpensive and efficient way of conducting this type of research. It allows one to identify a large number of the odor‐causing compounds found in LSM, and more importantly, to detect with some precision specific differences in the amounts of these compounds between peat types. 相似文献
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Brian K. Richards Brendan M. Schulte Arik Heilig Tammo S. Steenhuis Murray B. McBride Ellen Z. Harrison Philip Dickson 《Journal of the American Water Resources Association》2004,40(4):1025-1042
ABSTRACT: Farms that once spread only manures are now also applying sewage biosolids (sludge) and/or other wastes such as those from food processing. The objective of this study was to monitor environmental impacts at a dairy farm applying these materials. Fields were selected representing recent waste applications of manure (M1, M2), sewage biosolids (B1, B2), or fertilizer only control (F1, F2), although most fields had historical biosolids applications. Fields representing each treatment were not experimental replicates because of varying applications and soil characteristics. Septage and food processing wastes were also applied. Soil percolates were collected with wick lysimeters. Runoff was sampled at seven stream sites. Test field soils and alfalfa (Medicago sativa) were analyzed for trace elements. Cumulative trace metal loadings were low, at most only 1 percent of USEPA Part 503 limits. Surface soil enrichment was most evident for Mo, P, and S. Alfalfa tissue showed no trends of concern. The B2 site had the greatest percolate concentrations for 6 of 13 elements. Percolate Cu was somewhat elevated at Sites M1, M2, B2, and Fl. Percolate sodium was elevated on all M and B fields and sulfur was greatest at M2, B1, and B2. Soluble orthophosphate correlated with stream discharge during intensive monitoring of Stream Sites S1 (fertilizer) and S2 (biosolids). Peaks in S2 streamwater Mo lagged large runoff events by five days. Total streamwater export of Cu, Na, Mo, and soluble P were greater from the S2 biosolids subwatershed than from the S1 fertilizer subwatershed. Percolate concentrations exceeded corresponding streamwater concentrations in most cases. 相似文献
187.
IntroductionInrecentyears,intensiveanimalproductionhasresultedinhighdensityofanimalsinsmallareas,producinglargequantitiesofwastewithinsufficientnearbylandforapplication .InHongKong ,thepigindustryhasseenasteadygrowthinrecentyears .Itresultedinindiscrimin… 相似文献
188.
Woo-Jung Choi Gwang-Hyun Han Sang-Mo Lee Goon-Taek Lee Kwang-Sik Yoon Soo-Myung Choi Hee-Myong Ro 《Agriculture, ecosystems & environment》2007,120(2-4):259-268
An understanding of the long-term changes in the nitrate contamination pattern of unconfined groundwater is critical to conservation of drinking water in rural areas supporting mixed land-use activities such as cropping, livestock farming, and residence. To examine the effect of different land-use activities on nitrate contamination, groundwater samples were collected monthly for 3 years (1997–1999) from 12 wells in rural areas with different land-use activities and analyzed for the concentrations and N isotopic ratios (δ15N) of nitrate. The characteristics of nitrate contamination clearly differed with land-use activities. The percentages of samples that had a nitrate concentration exceeding the national standard for drinking water (10 mg N L−1) were 0, 23, 43, and 67% for the uncontaminated natural area, cropping area, cropping-livestock farming complex area, and residential area, respectively. The range of δ15N values was between +1.4 and +4.5‰ for groundwater nitrate from the uncontaminated natural area. In the cropping area, the δ15N values were slightly different with the type of fertilizer applied to fields in the vicinity of the well, and the values ranged between +8.7 and +14.4‰ for the compost-applied area and between +4.5 and +8.5‰ for the area where urea was applied with compost. The δ15N values of the cropping-livestock farming complex area ranged from +1.0 to +17.7‰, probably resulting from mixed contamination sources (inorganic fertilizer and livestock manure). The well located closest to the livestock feedlot had relatively higher δ15N values, with a range between +8.7 and +17.6‰. In the residential area, a higher δ15N (most frequently above +10‰) of nitrate suggested that the major source of contamination was effluent from leaky septic tanks. Our data showed that unconfined groundwater is susceptible to land-use activities above the aquifers, and the impacts of the activities could be more precisely inferred from long-term data on the concentration and δ15N of nitrate. By determining the impacts, more effective (specific to contamination sources) measures for preventing groundwater quality could be implemented. 相似文献
189.
N2O emissions from agricultural soils in the North China Plain:the effect of chemical nitrogen fertilizer and organic manure 总被引:1,自引:0,他引:1
IntroductionNitrousoxide (N2 O)isaveryimportantgreenhousegasintheatmosphere.InterestintheincreaseofatmosphericN2 OhasbeenrecentlystimulatedbytheunderstandingthatN2 Ogasplaysanimportantroleinthechemistryandozonelayerdestructionofthestratosphere.Theradiativ… 相似文献
190.