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Swine (Sus scofa domestica) lagoon effluent is a valuable resource. In the U.S. Mid-South it is applied from April to September to fertilize grass hay in spray-irrigated fields. Lagoon levels of nutrients and bacteria, and soil levels of nutrients have been documented, but little was known of effluent bacterial levels in soil. The present study examined levels of selected effluent bacteria and nutrients in soils inside and outside spray fields after >15 yr of effluent irrigation. Samples were collected February to March 2009 from contiguous soils spanning adjacent irrigated and nonirrigated areas. Separate soil cores for bacterial and nutrient tests were collected in pairs <10 cm apart. Five cores each were collected at 15-m intervals and combined, respectively, to comprise inside and outside samples from each of 20 soils (four each from five farms/spray fields). Analyses of data combined across all soils showed higher pH and Mehlich-3-extracrable (M3-) P, Mg, K, Na, Cu, and Zn inside than outside spray fields, while total N, total C, M3-Ca, and M3-Mn did not differ. Bacterial levels were higher inside than outside spray fields for heterotrophic plate counts, thermotolerant coliforms, Staphylococcus spp., and Clostridium perfringens, but levels of Escherichia coli and Enterococcus spp. were not different. Cultural presence/absence tests for three pathogens (Listeria spp., Campylobacter spp., and Salmonella spp.) detected only Listeria spp., which did not differ inside (23% positive samples) and outside (28% positive). Molecular tests detected all three pathogens at low levels that were not different inside and outside. We found no evidence of cumulative buildup of Campylobacter spp., Listeria spp., or Salmonela s. in spray field soils.  相似文献   
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In this study, cloud point extraction was used for the preconcentration of Al3+ ion after the complex formation with 1,4-dihydroxy-9,10-anthraquinone (Quinizarin [QUIN]), and subsequent analysis by spectrophotometeric method, using Triton X-114 as surfactant. The optimal extraction and reaction conditions were studied (i.e., pH?=?5.5, 0.1 mM QUIN, Triton X-114?=?0.1 % (w/v)), and the analytical characteristics of the method (e.g., limit of detection, linear range, preconcentration, and enrichment factors) were obtained. Linearity was obeyed in the range of 3.33–166.67 ng ml?1 of Al3+ ion. The detection limit of the method was 2.09 ng ml?1 for Al3+ ion. The interference effect of some anions and cations was also tested. The method was applied to determine Al3+ ion in water samples.  相似文献   
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The Energy Policy Act of 1992 motivated transit agencies to utilize alternative-fuel transit buses in addition to their popular diesel buses. Transit agencies have planned to add a significant number of alternative-fuel buses to their current transit fleets. This study is to inform policy makers who may allocate public funds for alternative-fuel bus projects to make a smarter decision in this regard. For each of the eight alternative-fuel buses, technologies introduced by the ACT, fuel efficiency, life-cycle cost (LCC) and emission are estimated and compared with the available information for the ultralow-sulfur diesel (ULSD) fuel buses. A case study in the State of Delaware is presented to demonstrate how the proposed approaches can be employed to evaluate the relative importance of the most viable alternative-fuel transit buses according to the predefined set of criteria. The results show that buses propelled by hybrid-diesel engine have the least LCC and emissions and are the most suitable alternative for the ULSD buses in the short- and midterm.  相似文献   
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In Mississippi, spent poultry litter is used as fertilizer. Nutrient and bacterial levels in litter and nutrient levels in litter-fertilized (L+) soil are known, but less is known of bacterial levels in L+ soil. This study compared contiguous L+ and non-litter-fertilized (L-) soils comprising 15 soil types on five farms in April through May 2009. Levels of pH; NO-N; and Mehlich-3-extractable (M3) and water-extractable (WE) P, Ca, K, and Cu were higher in L+ than in L- soil. Total C; total N; NH-N; and M3 and WE Na, Fe, and Zn did not differ in L+ and L- soil. Bacterial levels were higher in 0- to 5-cm than in 5- to 10-cm cores. Levels were higher in L+ than in L- soil for culturally determined heterotrophic plate counts and staphylococci and were lower for total bacteria estimated by quantitative polymerase chain reaction (qPCR) of 16S rRNA, but cultural levels of thermotolerant coliforms, , , and enterococci were not different. Cultural presence/absence (CPA) tests and qPCR for spp., spp., and spp. detected only spp., which did not differ in L+ (CPA = 77% positive samples; mean qPCR = 0.65 log genomic units [gu] g) and L- (CPA = 70% positive samples; mean qPCR = 0 log gu g) soils. Litter applications were associated with higher levels of pH, P, Cu, heterotrophic plate counts, and staphylococci. Fecal indicator and enteric pathogen levels were not affected. We conclude that, although some litter-derived nutrients and bacteria persisted between growing seasons in L+ soils, enteric pathogens did not.  相似文献   
5.
Energy-efficient and environmentally sustainable public transportation systems are within the solution space provided by alternative fuel vehicles. Given the large revenue service potential of alternative fuel buses within the urban space, they are good candidates for emissions reductions when they are employed as part of a comprehensive urban transit planning process. The determination of the most appropriate alternative fuel bus asset for a given application is not necessarily that straightforward. The typical bus fleet is developed over a broad time horizon with each asset being acquired to meet a certain agency need or to close a perceived gap in the delivery of public transportation service. Therefore, as new assets are considered, it is critical for the fleet manager to consider as many factors of the fleet infrastructure to better ensure the positive impact that the newly acquired asset will have on fleet performance relative to the overall service goals and objectives of the fleet. This study investigates a broad range of alternative fuel bus technologies and the associated factors that will inform the decision-making process. Further, this work utilizes the inventory and understanding of the range of technology factors and leverages the perspective knowledge of industry experts on each of these factors to develop an expert systems decision-making philosophy to aid in the adoption of industry standards, best practices, consistency and sustainability in fleet asset management over time.  相似文献   
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Environmental Science and Pollution Research - Water quality of lakes, estuaries, and coastal areas serves as an indicator of the overall health of aquatic ecosystems as well as the health of the...  相似文献   
8.
It is often necessary to find a simpler method in different climatic regions to calculate reference crop evapotranspiration (ETo) since the application of the FAO‐56 Penman‐Monteith method is often restricted due to the unavailability of a comprehensive weather dataset. Seven ETo methods, namely the standard FAO‐56 Penman‐Monteith, the FAO‐24 Radiation, FAO‐24 Blaney Criddle, 1985 Hargreaves, Priestley‐Taylor, 1957 Makkink, and 1961 Turc, were applied to calculate monthly averages of daily ETo, total annual ETo, and daily ETo in an arid region at Aksu, China, in a semiarid region at Tongchuan, China, and in a humid region at Starkville, Mississippi, United States. Comparisons were made between the FAO‐56 method and the other six simple alternative methods, using the index of agreement D, modeling efficiency (EF), and root mean square error (RMSE). For the monthly averages of daily ETo, the values of D, EF, and RMSE ranged from 0.82 to 0.98, 0.55 to 0.98, and 0.23 to 1.00 mm/day, respectively. For the total annual ETo, the values of D, EF, and RMSE ranged from 0.21 to 0.91, ?43.08 to 0.82, and 24.80 to 234.08 mm/year, respectively. For the daily ETo, the values of D, EF, and RMSE ranged from 0.58 to 0.97, 0.57 to 0.97, and 0.30 to 1.06 mm/day, respectively. The results showed that the Priestly‐Taylor and 1985 Hargreaves methods worked best in the arid and semiarid regions, while the 1957 Makkink worked best in the humid region.  相似文献   
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