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1.
Russian Journal of Ecology - Climate change entails shifts in the ranges of woody plants along both latitudinal and altitudinal gradients in the boreal forest biome. In this study,...  相似文献   
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Environmental Science and Pollution Research - Aedes aegypti and Culex quinquefasciatus are vectors of diseases that constitute public health problems. The discovery of products capable of...  相似文献   
4.
Phyllanthus niruri is a plant that is used to prevent calcium oxalate crystallisation and to block the stone formation in urolithiasis. Contaminants in the environment can be readily taken up by medicinal plants due to their ability to absorb chemicals into their tissues. If contaminated plants are ingested, they have the potential to negatively affect human and environmental health. The aim of this study was to assess contamination in the soil and the medicinal plant P. niruri by cadmium (Cd) in ceramic industrial areas of Monte Carmelo, Brazil. Soil samples and plant samples (divided in root, shoot and leaves) were collected from a contaminated monitoring site and from a rural area (which was used as a reference site for comparative purposes). The Cd concentrations of the samples were analysed with an atomic absorption spectrometer. P. niruri was found to be sensitive to soil contamination by Cd that was attributed to ceramic industrial emissions. The results revealed that Cd bioaccumulation in the roots and shoots of P. niruri was associated with a significant increase (p?<?0.05) in the concentration of active lignan compounds (phyllanthin and hypophyllanthin) in the leaves. The identification of high concentrations of Cd and active lignan compounds suggests a risk of contamination of the site and the risk of a high dose of Cd to people exposed at the site.  相似文献   
5.
Greenhouse gas emissions assessments for site cleanups typically quantify emissions associated with remediation and not those from contaminant biodegradation. Yet, at petroleum spill sites, these emissions can be significant, and some remedial actions can decrease this additional component of the environmental footprint. This article demonstrates an emissions assessment for a hypothetical site, using the following technologies as examples: excavation with disposal to a landfill, light nonaqueous‐phase liquid (LNAPL) recovery with and without recovered product recycling, passive bioventing, and monitored natural attenuation (MNA). While the emissions associated with remediation for LNAPL recovery are greater than the other considered alternatives, this technology is comparable to excavation when a credit associated with product recycling is counted. Passive bioventing, a green remedial alternative, has greater remedial emissions than MNA, but unlike MNA can decrease contaminant‐related emissions by converting subsurface methane to carbon dioxide. For the presented example, passive bioventing has the lowest total emissions of all technologies considered. This illustrates the value in estimating both remediation and contaminant respiration emissions for petroleum spill sites, so that the benefit of green remedial approaches can be quantified at the remedial alternatives selection stage rather than simply as best management practices. ©2015 Wiley Periodicals, Inc.  相似文献   
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Environmental Science and Pollution Research - The reduction of estrogen levels, as a result of menopause, is associated with the development of metabolic diseases caused by alterations in...  相似文献   
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The use of petroleum-derived products should be avoided regarding the principles of green and sustainable chemistry. The work reported herein, is aimed at the liquefaction of pine shavings for the production of an environmentally-friendly polyol suitable to be used in the formulations of sprayable polyurethane foams. The biopolyols were obtained in high yield and were used to replace those derived from fossil sources, to produce more “greener” polyurethane foams and therefore, less dependent on petroleum sources, since the polyol component was substituted by products resulting from biomass liquefaction. The partial and fully exchange of the polyols was accomplished, and the results compared with a reference foam. The foams were afterward, chemical, physical, morphological, and mechanically characterized. The complete replacement of polyether polyol and polyol polyester has presented some similar characteristics as that used as a reference, validating that the path chosen for the development of more sustainable materials is on the right track for the contribution to a cleaner world.  相似文献   
8.
Dissipation and decontamination of chlorantraniliprole (Coragen 18.5 SC) in brinjal and okra fruits were studied following field application at single and double doses of 30 and 60 g ai ha?1, and the residues of the insecticide was estimated using LC-MS/MS. Initial residues of chlorantraniliprole at single and double doses on the fruits of brinjal were 0.72 and 1.48 mg kg?1, while on okra fruits, the residues were 0.48 and 0.91 mg kg?1, respectively. The residues reached below detectable level of 0.01 mg kg?1 on the 10th day. Half-life of chlorantraniliprole at 30 and 60 g ai ha?1 on brinjal was 1.58 and 1.80 days with the calculated waiting period of 0.69 and 2.38 days, whereas on okra, the values were 1.60 and 1.70 and 0 and 1.20 days, respectively. The extent of removal of chlorantraniliprole using simple decontaminating techniques at 2 h and 3 days after spraying was 40.99–91.37 % and 29.85–89.12 %, respectively, from brinjal fruits and 47.78–86.10 % and 41.77–86.48 %, respectively, from okra fruits.  相似文献   
9.
The Response of Hydrophytes to Environmental Pollution with Heavy Metals   总被引:3,自引:0,他引:3  
The effects of Cu2+, Cd2+, and Ni2+ at low and high concentrations (0.025 and 0.25 mg/ml) on the accumulation capacity, the state of the pigment complex, and photosynthesis rate have been studied in model experiments with three floating hydrophytes (Hydrocharis morsus-ranae L., Lemna gibba L., and Potamogeton natans L.) and four submerged hydrophytes (Elodea canadensis Michx., Lemna trisulka L., Ceratophyllum demersum L., and Potamogeton lucens L.). Copper and cadmium are especially toxic at the concentrations studied. The effect of Cu2+ was the strongest in hydatophytes, and the effect of Cd2+, in pleustophytes. It is hypothesized that the differences between hydrophytes with respect to accumulation of metals and decrease in photosynthesis rate may cause predominant elimination of submerged species. Therefore, changes in the species structure of hydrophyte communities may be expected in waters polluted with metals.  相似文献   
10.
Quantitative methods have been applied to the study of floristic structure and diversity in Samarskaya Luka. The results show that Samarskaya Luka is a floristically heterogeneous area in which six elementary floras can be distinguished. This area has been assessed as a floristically autonomous formation, and its floristic representativeness was estimated.  相似文献   
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