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971.
Concerns regarding the impacts of pesticides on aquatic species and drinking water sources have increased demands on water quality monitoring programs; however the costs of sample analysis can be prohibitive. In this study we investigated enzyme-linked immunosorbent assay (ELISA) as a cost-effective, high through-put method for measuring pesticide concentrations in surface waters. Seven hundred and thirty-nine samples from 158 locations throughout Ontario were analysed for atrazine and metolachlor from April to October 2007. Concentrations ranged from <0.1 to 3.91 μg L−1 (median = 0.12 μg L−1) for atrazine and from <0.1 to 1.83 μg L−1 (median = 0.09 μg L−1) for metolachlor. Peak concentrations occurred in late spring/early summer, in rural agricultural locations, and decreased over the remainder of the growing season for both herbicides. About 3% of the samples that had ELISA results occurring above the limit of quantification (0.10 μg L−1) were evaluated against gas chromatography-mass spectrometry (GC-MS). Linear regression analysis revealed a R2 value of 0.88 and 0.39, for atrazine and metolachlor, respectively. ELISA tended to overestimate concentrations for atrazine and metolachlor, most likely because the ELISA kits also detect their metabolites. Atrazine data suggest that ELISA may be used complementary with GC-MS analysis to enhance the spatial and temporal resolution of a water quality monitoring study. The commercially available metolachlor ELISA kit requires further investigation. ELISA may be used to detect atrazine and metolachlor in surface water samples, but it is not recommended as a quantitative replacement for traditional analytical methods. 相似文献
972.
Ochoa-Hueso R Allen EB Branquinho C Cruz C Dias T Fenn ME Manrique E Pérez-Corona ME Sheppard LJ Stock WD 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2265-2279
We review the ecological consequences of N deposition on the five Mediterranean regions of the world. Seasonality of precipitation and fires regulate the N cycle in these water-limited ecosystems, where dry N deposition dominates. Nitrogen accumulation in soils and on plant surfaces results in peaks of availability with the first winter rains. Decoupling between N flushes and plant demand promotes losses via leaching and gas emissions. Differences in P availability may control the response to N inputs and susceptibility to exotic plant invasion. Invasive grasses accumulate as fuel during the dry season, altering fire regimes. California and the Mediterranean Basin are the most threatened by N deposition; however, there is limited evidence for N deposition impacts outside of California. Consequently, more research is needed to determine critical loads for each region and vegetation type based on the most sensitive elements, such as changes in lichen species composition and N cycling. 相似文献
973.
Viana M Postigo C Querol X Alastuey A López de Alda MJ Barceló D Artíñano B López-Mahia P García Gacio D Cots N 《Environmental pollution (Barking, Essex : 1987)》2011,159(5):1241-1247
Levels of cocaine and other psychoactive substances in atmospheric particulate matter (PM) were determined in urban environments representing distinct social behaviours with regard to drug abuse: night-life, university and residential areas. Three cities (with population >1 million and <0.3 million inhabitants) were selected. Mean daily levels of drugs in PM were 11-336 pg/m3 for cocaine, 23-34 pg/m3 for cannabinoids, and 5-90 pg/m3 for heroin. The highest levels were recorded on weekends, with factors with respect to weekdays of 1-3 for cocaine, 1-2 for cannabinoids and 1.1-1.7 for heroin. Higher levels were detected in the night-life areas, pointing towards consumption and trafficking as major emission sources, and possibly ruling out drug manufacture. The similarities in temporal trends at all sites suggested a city-scale transport of psychoactive substances. Correlations were detected between cocaine and amphetamine consumption (r2 = 0.98), and between heroin and cannabinoids (r2>0.82). 相似文献
974.
It has been postulated that road deicing salts are sufficiently diluted by spring rains to ameliorate any physiological impacts to amphibians breeding in wetlands near roads. We tested this conjecture by exposing clutches of the spotted salamander (Ambystoma maculatum) to three chloride concentrations (1 mg/L, 145 mg/L, 945 mg/L) for nine days, then transferred clutches to control water for nine days, and measured change in mass at three-day intervals. We measured mass change because water uptake by clutches reduces risks to embryos associated with freezing, predation, and disease. Clutches in controls sequestered water asymptotically. Those in the moderate concentrations lost 18% mass initially and regained 14% after transfer to control water. Clutches in high concentration lost 33% mass and then lost an additional 8% after transfer. Our results suggest that spring rains do not ameliorate the effects of deicing salts in wetlands with extremely high chloride concentrations. 相似文献
975.
Onandia G Olsson AK Barth S King JS Uddling J 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):2350-2354
With rising concentrations of both atmospheric carbon dioxide (CO2) and tropospheric ozone (O3), it is important to better understand the interacting effects of these two trace gases on plant physiology affecting land-atmosphere gas exchange. We investigated the effect of growth under elevated CO2 and O3, singly and in combination, on the primary short-term stomatal response to CO2 concentration in paper birch at the Aspen FACE experiment. Leaves from trees grown in elevated CO2 and/or O3 exhibited weaker short-term responses of stomatal conductance to both an increase and a decrease in CO2 concentration from current ambient level. The impairement of the stomatal CO2 response by O3 most likely developed progressively over the growing season as assessed by sap flux measurements. Our results suggest that expectations of plant water-savings and reduced stomatal air pollution uptake under rising atmospheric CO2 may not hold for northern hardwood forests under concurrently rising tropospheric O3. 相似文献
976.
Pérez-de-Mora A Madejón P Burgos P Cabrera F Lepp NW Madejón E 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):3018-3027
We investigated the efficiency of various by-products (sugarbeet lime, biosolid compost and leonardite), based on single or repeated applications to field plots, on the establishment of a vegetation cover compatible with a stabilization strategy on a multi-element (As, Cd, Cu, Pb and Zn) contaminated soil 4-6 years after initial amendment applications. Results indicate that the need for re-treatment is amendment- and element-dependent; in some cases, a single application may reduce trace element concentrations in above-ground biomass and enhance the establishment of a healthy vegetation cover. Amendment performance as evaluated by % cover, biomass and number of colonizing taxa differs; however, changes in plant community composition are not necessarily amendment-specific. Although the translocation of trace elements to the plant biotic compartment is greater in re-vegetated areas, overall loss of trace elements due to soil erosion and plant uptake is usually smaller compared to that in bare soil. 相似文献
977.
Assessment of heavy metal pollution from a Fe-smelting plant in urban river sediments using environmental magnetic and geochemical methods 总被引:7,自引:0,他引:7
Zhang C Qiao Q Piper JD Huang B 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):3057-3070
Environmental magnetic proxies provide a rapid means of assessing the degree of industrial heavy metal pollution in soils and sediments. To test the efficiency of magnetic methods for detecting contaminates from a Fe-smelting plant in Loudi City, Hunan Province (China) we investigated river sediments from Lianshui River. Both magnetic and non-magnetic (microscopic, chemical and statistical) methods were used to characterize these sediments. Anthropogenic heavy metals coexist with coarse-grained magnetic spherules. It can be demonstrated that the Pollution Load Index of industrial heavy metals (Fe, V, Cr, Mo, Zn, Pb, Cd, Cu) and the logarithm of saturation isothermal remanent magnetization, a proxy for magnetic concentration, are significantly correlated. The distribution heavy metal pollution in the Lianshui River is controlled by surface water transport and deposition. Our findings demonstrate that magnetic methods have a useful and practical application for detecting and mapping pollution in and around modern industrial cities. 相似文献
978.
De Laender F Van den Brink PJ Janssen CR 《Environmental pollution (Barking, Essex : 1987)》2011,159(10):3009-3017
An extensive data set describing effects of the herbicide linuron on macrophyte-dominated microcosms was analysed with a food web model to assess effects on ecosystem functioning. We showed that sensitive phytoplankton and periphyton groups in the diets of heterotrophs were gradually replaced by more tolerant phytoplankton species as linuron concentrations increased. This diet shift--showing redundancy among phytoplankton species--allowed heterotrophs to maintain their functions in the contaminated microcosms. On an ecosystem level, total gross primary production was up to hundred times lower in the treated microcosms but the uptake of dissolved organic carbon by bacteria and mixotrophs was less sensitive. Food web efficiency was not consistently lower in the treated microcosms. We conclude that linuron predominantly affected the macrophytes but did not alter the overall functioning of the surrounding planktonic food web. Therefore, a risk assessment that protects macrophyte growth also protects the functioning of macrophyte-dominated microcosms. 相似文献
979.
Kabra AN Khandare RV Kurade MB Govindwar SP 《Environmental science and pollution research international》2011,18(8):1360-1373
Purpose
The dyes and dye stuffs present in effluents released from textile dyeing industries are potentially mutagenic and carcinogenic. Phytoremediation technology can be used for remediating sites contaminated with such textile dyeing effluents. The purpose of the work was to explore the potential of Glandularia pulchella (Sweet) Tronc. to decolorize different textile dyes, textile dyeing effluent, and synthetic mixture of dyes. 相似文献980.
Stefanie Grund Eric Higley René Schönenberger Marc J-F. Suter John P. Giesy Markus Hecker Henner Hollert 《Environmental science and pollution research international》2011,18(3):446-460