超高效液相色谱/三重四极杆质谱联用(ACQUITY UPLC/Xevo TQ-S)检测蜂花粉中吡虫啉残留量

正在分析复杂环境样品中的痕量污染物时,通常会受到基质的严重干扰,使得在进行亚ng·g-1浓度水平检测时,所用仪器面临着必须满足灵敏度要求的挑战.杀虫剂暴露会对蜂群产生致死和亚致死效应,若要监控这些效应带来的影响则需要对蜜蜂和蜂产品中的杀虫剂水平进行可靠定量.某地区使用吡虫啉杀虫剂来应对昆虫的侵害,我们对该地区的蜜蜂样本及花粉产品进行了吡虫啉残留分析,花粉中平均含有20%蛋白质和6%总脂肪,并且还含有大量的维生素、脂肪酸、     

Production of carbon-based precursor from non-recyclable waste poly(ethylene) terephthalate: effect of multilayer structure on carbonized product

Journal of Material Cycles and Waste Management - In this paper, the carbonization of multilayer PET containing an oxygen barrier layer was investigated. The oxygen barrier layer was identified as...     

Detecting and quantifying reductive dechlorination under monitored natural attenuation conditions

Field sampling and testing were used to investigate the relationship between baseline geochemical and microbial community data and in situ reductive dechlorination rates at a site contaminated with trichloroethene (TCE) and carbon tetrachloride (CTET). Ten monitoring wells were selected to represent conditions along groundwater flow paths from the contaminant source zone to a wetlands groundwater discharge zone. Groundwater samples were analyzed for a suite of geochemical and microbial parameters; then push‐pull tests with fluorinated reactive tracers were conducted in each well to measure in situ reductive dechlorination rates. No exogenous electron donors were added in these tests, as the goal was to assess in situ reductive dechlorination rates under natural attenuation conditions. Geochemical data provided preliminary evidence that reductive dechlorination of TCE and CTET was occurring at the site, and microbial data confirmed the presence of known dechlorinating organisms in groundwater. Push‐pull tests were conducted using trichlorofluoroethene (TCFE) as a reactive tracer for TCE and, in one well, trichlorofluoromethane (TCFM) as a reactive tracer for CTET. Injected TCFE was transformed to cis‐ and trans‐dichlorofluoroethene and chlorofluoroethene, and, in one test, injected TCFE was completely dechlorinated to fluoroethene (FE). In situ TCFE transformation rates ranged from less than 0.005 to 0.004/day. In the single well tested, injected TCFM was transformed in situ to dichlorofluoromethane and chlorofluoromethane; the TCFM transformation rate was estimated as 0.001/day. The results indicate that it is possible to use push‐pull tests with reactive tracers to directly detect and quantify reductive dechlorination of chlorinated ethenes and ethanes under monitored natural attenuation conditions, which has not previously been demonstrated. Transformation rate estimates obtained with these techniques should improve the accuracy of contaminant transport modeling. © 2012 Wiley Periodicals, Inc.     

Using Ecological Risk Assessment to Identify the Major Anthropogenic Stressor in the Waquoit Bay Watershed,Cape Cod,Massachusetts

The Waquoit Bay Watershed ecological risk assessment was performed by an interdisciplinary and interagency workgroup. This paper focuses on the steps taken to formulate the analysis plan for this watershed assessment. The workgroup initially conducted a series of meetings with the general public and local and state managers to determine environmental management objectives for the watershed. The workgroup then decided that more information was needed on the impacts of six stressors: nutrient enrichment, physical alteration of habitat, altered freshwater flow, toxic chemicals, pathogens, and fisheries harvesting. Assessment endpoints were selected to establish the link between environmental management objectives, impacts of stressors, and scientifically measurable endpoints. The following assessment endpoints were selected: estuarine eelgrass cover, scallop abundance, finfish diversity and abundance, wetland bird distribution and abundance, piping plover distribution and abundance, tissue contaminant levels, and brook trout distribution and abundance in streams. A conceptual model was developed to show the pathways between human activities, stressors, and ecological effects. The workgroup analyzed comparative risks, by first ranking stressors in terms of their potential risk to biotic resources in the watershed. Then stressors were evaluated by considering the components of stressors (e.g., the stressor chemical pollution included both heavy metals and chlorinated solvents components) in terms of intensity and extensiveness. The workgroup identified nutrient enrichment as the major stressor. Nutrient enrichment comprised both phosphorus enrichment in freshwater ponds and nitrogen enrichment within estuaries. Because phosphorus impacts were being analyzed and mitigated by the Air Force Center for Environmental Excellence, this assessment focused on nitrogen. The process followed to identify the predominant stressor and focus the analyses on nitrogen impacts on eelgrass and scallops will serve as an example of how to increase the use of the findings of a watershed assessment in decision making.     

Jack pine growth and elemental composition are affected by saline tailings water

In the processing of oil sands from Alberta's Athabasca formation, large quantities of alkaline, saline tailings and associated process-affected waters are produced. These waters may have a negative effect on plants used in reclamation of mined areas in this region of the northern boreal forest. In the present study, we examined the effects of process-affected water on the growth and elemental composition of jack pine (Pinus banksiana Lamb.) seedlings. Seedlings were grown in sand culture, and treated with tailings water to which mineral nutrients had been added. One-month-old seedlings were treated for 14 d, and all measured growth parameters were reduced. Growth and shoot elemental composition were also measured in seven-month-old seedlings that were treated for 10 wk with process-affected water. Shoots had significantly elevated levels of Na, Cl, S, P, B, and Sr, and significantly reduced levels of Fe, Mo, Ba, and K. The relationships between elemental composition and seedling growth and injury were examined using multiple regression. Growth rates, dry weights, and carotenoid content were reduced, but were not related to shoot elemental composition. Needle necrosis was positively related to tissue Na and Cl. Results indicate that reclamation planning must consider substrate Na and Cl levels when planting jack pine on tailings-affected sites.     

Habitat Assessment of Non-Wadeable Rivers in Michigan

Habitat evaluation of wadeable streams based on accepted protocols provides a rapid and widely used adjunct to biological assessment. However, little effort has been devoted to habitat evaluation in non-wadeable rivers, where it is likely that protocols will differ and field logistics will be more challenging. We developed and tested a non-wadeable habitat index (NWHI) for rivers of Michigan, where non-wadeable rivers were defined as those of order ≥5, drainage area ≥1600 km², mainstem lengths ≥100 km, and mean annual discharge ≥15 m³/s. This identified 22 candidate rivers that ranged in length from 103 to 825 km and in drainage area from 1620 to 16,860 km². We measured 171 individual habitat variables over 2-km reaches at 35 locations on 14 rivers during 2000–2002, where mean wetted width was found to range from 32 to 185 m and mean thalweg depth from 0.8 to 8.3 m. We used correlation and principal components analysis to reduce the number of variables, and examined the spatial pattern of retained variables to exclude any that appeared to reflect spatial location rather than reach condition, resulting in 12 variables to be considered in the habitat index. The proposed NWHI included seven variables: riparian width, large woody debris, aquatic vegetation, bottom deposition, bank stability, thalweg substrate, and off-channel habitat. These variables were included because of their statistical association with independently derived measures of human disturbance in the riparian zone and the catchment, and because they are considered important in other habitat protocols or to the ecology of large rivers. Five variables were excluded because they were primarily related to river size rather than anthropogenic disturbance. This index correlated strongly with indices of disturbance based on the riparian (adjusted R² = 0.62) and the catchment (adjusted R² = 0.50), and distinguished the 35 river reaches into the categories of poor (2), fair (19), good (13), and excellent (1). Habitat variables retained in the NWHI differ from several used in wadeable streams, and place greater emphasis on known characteristic features of larger rivers.     

Phosphorus leaching in manure-amended Atlantic Coastal Plain soils

Targeting the sources of phosphorus (P) and transport pathways of drainage from agricultural land will assist in the reduction of P loading to surface waters. Our research investigated the vertical movement of P from dairy manure and broiler litter through four Atlantic Coastal Plain soils. A randomized split-plot design with two main-plot tillage treatments (no tillage [NT] and chisel tillage [CH]) and five manure P rate split-plot treatments was used at each location. The split-plot P rates were 0, 100, 200, 300, and 400 kg P ha(-1) yr(-1). Four consecutive years of manure application began at all sites 5 yr before sampling. Soils were sampled to a depth of 150 cm from each split plot in seven depth increments and analyzed for soil test phosphorus (STP), water-extractable soil phosphorus (WSP), and degree of phosphorus saturation (DPS). The DPS of the 0- to 15-cm depths confirmed that at the 100 kg P ha(-1) yr(-1) application rate, all sites exceeded the threshold for P saturation (30%). At depths greater than 30 cm, DPS was typically below the 30% saturation threshold. The DPS change points ranged from 25 to 34% for the 0- to 90-cm depths. Our research concluded that the risk of P leaching through the matrix of the Atlantic Coastal Plain soils studied was not high; however, P leaching via macropore bypass may contribute to P loss from these soils.     

Human impacts on Australia's Indian Ocean tropical island ecosystems: A review

Summary The human impact on two tropical island groups in the eastern Indian Ocean — Christmas Island and the Cocos (Keeling) Islands — is described. Both are external territories of the Commonwealth of Australia. The ecological influences of construction, war, coconut plantations, horticulture, mining, the introduction of organisms and tourism are discussed in relation to the islands' geomorphology, hydrology, vegetation, fauna and marine environments.Although there are significant differences in the environment between Christmas Island and Cocos, there are marked parallels in their ecological history. Despite these islands being extremely remote, economic, political and technological changes in the outside world have had substantial effects.There are signs that conservation values in land and resource management on these islands are now being addressed. However, these islands, in common with coral islands and atolls elsewhere, may be on the threshold of a tourism boom, with significant implications for the islands' hydrology as well as their animal and plant communities.Dr Patrick H. Armstrong is a Senior Lecturer in the Department of Geography at the University of Western Australia. An early version of this paper was given to the ASEAN Geography Conference, in Brunei, in June 1990.     

Polaroid's environmental accounting and reporting system: Benefits and limitations of a tqem measurement tool

Polaroid Corporation has established an ambitious pollution prevention program that calls for reducing chemical use and waste by 10 percent per unit per year during the period 1988 to 1993. A notable aspect of Polaroid'S efforts is the environmental accounting and reporting system (EARS) it has developed to measure progress toward this goal. EARS is a Total Quality Environmental Management tool with applicability in similar industries.