The fate and effects of CuO nanoparticles (CuO NPs) were examined in endobenthic species (Scrobicularia plana , Hediste diversicolor), under environmentally realistic conditions in outdoor mesocosms (exposure to Cu at 10 μg L(-1) in particulate (CuO NPs) or soluble salt (CuNO(3)) forms) for 21 days. Labile Cu was determined in water and sediment by using diffusive gradient in thin films. No labile Cu being detected from CuO NPs; the observed effects in invertebrates exposed to CuO NPs were mainly attributed to the toxicity of nanoparticulate rather than dissolved Cu toxicity. Bioaccumulation of CuO NPs was observed in both species. Biomarkers were examined at different levels of biological organization: biochemical markers of defense and damage, biomarkers of genotoxicity (comet assay), and behavioral biomarkers (feeding and burrowing). Behavioral biomarkers, antioxidant defenses (catalase, glutathion S-transferase, metallothionein), and genotoxicity are the most sensitive tools to highlight the effect of soluble or nanoparticulate metal forms. Concerning other biomarkers of defense (superoxide dismutase, lactate dehydrogenase, laccase) and damage (thiobarbituric acid reactive substances, acetylcholinesterase, acid phosphatase), no significant effects were detected. This experiment shows the suitability of mesocosms for studying the environmental effects of nanoparticles.
The assessment of physico-chemical properties in forest soils affected by fires was evaluated using near infrared reflectance (NIR) spectroscopy coupled with chemometric methods. In order to describe the soil properties, measurements were taken of the total organic carbon on solid phase, the total nitrogen content, the organic carbon and the specific absorbences at 254 and 280 nm of humic substances, organic carbon in humic and fulvic acids, concentrations of NH(4)(+), Ca(2+), Mg(2+), K(+) and phosphorus in addition to NIR spectra. Then, a fire recurrence index was defined and calculated according to the different fires extents affecting soils. This calculation includes the occurrence of fires as well as the time elapsed since the last fire. This study shows that NIR spectroscopy could be considered as a tool for soil monitoring, particularly for the quantitative prediction of the total organic carbon, total nitrogen content, organic carbon in humic substances, concentrations of phosphorus, Mg(2+), Ca(2+) and NH(4)(+) and humic substances UVSA(254). Further validation in this field is necessary however, to try and make successful predictions of K(+), organic carbon in humic and fulvic acids and the humic substances UVSA(280). Moreover, NIR coupled with PLS can also be useful to predict the fire recurrence index in order to determine the spatial variability. Also this method can be used to map more or less burned areas and possibly to apply adequate rehabilitation techniques, like soil litter reconstitution with organic enrichments (industrial composts) or reforestation. Finally, the proposed recurrence index can be considered representative of the state of the soils.
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