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231.

Selenium (Se) biofortification of staple cereal crops can improve the Se nutritional status of populations. A field trial employing an enriched stable isotope of Se (77Se) was undertaken over three consecutive cropping seasons in a coarse-textured, calcareous soil in Gilgit-Baltistan, Pakistan. The objectives were to (1) assess the feasibility and efficiency of Se biofortification, (2) determine the fate of residual Se, and (3) assess the consequences for dietary Se intake. Isotopically enriched 77Se (77SeFert) was applied, either as selenate or as selenite, at three levels (0, 10, and 20 g ha?1) to a wheat crop. Residual 77SeFert availability was assessed in subsequent crops of maize and wheat without further 77SeFert addition. Loss of 77SeFert was c.35% by the first (wheat) harvest, for both selenium species, attributable to the practice of flood irrigation and low adsorption capacity of the soil. No 77SeFert was detectable in subsequent maize or wheat crops. The remaining 77SeFert in soil was almost entirely organically bound and diminished with time following a reversible (pseudo-)first-order trend. Thus, repeat applications of Se would be required to adequately biofortify grain each year. In contrast to native soil Se, there was no transfer of 77SeFert to a recalcitrant form. Grain from control plots would provide only 0.5 µg person?1 day?1 of Se. By contrast, a single application of 20 g ha?1 SeVI could provide c. 47 µg person?1 day?1 Se in wheat, sufficient to avoid deficiency when combined with dietary Se intake from other sources (c. 25 µg day?1).

  相似文献   
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233.
Swimming pool users are a source of various contaminants and microorganisms. Conventional chlorine-based reagents treatment is commonly used to disinfect water. However, this disinfection treatment has serious serious health issues such as formation of carcinogenic by-products, i.e., trihalomethanes. In order to prevent this problem, an electrochemical disinfection process was carried out using synthetic and real swimming pool waters. The performance of the electrochemical system was evaluated by studying the effect of current intensity (0.5–3.0 A), treatment time, type of anode (Nb/BDD and Ti/Pt) and the initial concentration of pathogens Escherichia coli and P. aeruginosa. Results show that real swimming pool water, initially containing 106 CFU/100 mL of pathogens, was disinfected at current intensities of 1.5 and 3.0 A using, respectively, Nb/BDD and Ti/Pt as anode materials (CFU: colony-forming units, BDD: boron-doped diamond). This work is also one of the few showing the up-scaling of electrochemical disinfection of real swimming pool water at large volumes of 100 L.  相似文献   
234.
Environmental Chemistry Letters - Global warming is partly caused by massive emissions of carbon dioxide (CO2), a greenhouse gas, in the atmosphere by industrial and other human activities....  相似文献   
235.
The identification and assessment of project risks among potential risks can be considered a multi-attribute group decision making (MAGDM) problem including both quantitative and qualitative criteria. We extend the concept of safety to risk identification and assessment; this is to emphasize that the focus should not only be on the time and cost criteria, but also on the health, safety and environment (HSE) criterion. Conventional approaches to risk identification and risk assessment separately tend to be less effective in dealing with the imprecise of the risk assessment individually. The aim of this paper is to present a new methodology for identifying and assessing risks simultaneously by applying MAGDM technique. This paper includes a new procedure for classifying potential risks which it is named potential risk breakdown structure (PRBS) based on project work breakdown structure (WBS). Nominal group technique (NGT) is utilized for gathering potential risks. Obtained results have been applied in gas refinery plant construction successfully.  相似文献   
236.
Land degradation by soil erosion is a socioeconomic and environmental problem facing many developing countries. Application of stonewall terraces for soil moisture conservation is vital to reducing the environmental impacts of this phenomenon. To this end, a field plot experiment was conducted in the study area along with the use of a closed-ended questionnaire. The object of the experiment was to study the socioeconomic impacts of soil erosion on local farmers and their adoption of the stonewall terrace technique. The study showed a higher net profit in areas that had implemented terrace conservation practices than in areas that had not (i.e., 3.5 to 6 times higher net profit). Correlation analysis indicated that the farmers’ perceptions, land ownership, and geomorphology were significantly related to the farmers’ incentives and willingness to adopt terraces as soil conservation measures (P < 0.05), although the correlations were negative. Smallholder farmers (52% of the interviewed farmers) were involved in the sale of the agricultural land for urban uses, largely because of the high price and immediate returns offered. However, the associated land use changes warrant greater involvement of both the private and public sectors. This cooperation may be accomplished through the introduction of a long-term agricultural loan system and the development of proper legislation accompanied by a comprehensive and durable infrastructure and service system with the goal of reducing the negative impact of land use changes and encouraging sustainable use of resources.  相似文献   
237.
Environmental Science and Pollution Research - This study was designed to assess the gradual increase in the use of insecticides on vegetables and to familiarize the consumers regarding the...  相似文献   
238.
Environmental Science and Pollution Research - Climate change is occurring and is influencing biological systems through augmented temperatures, more inconstant precipitation, and rising CO2 in the...  相似文献   
239.
Environmental and Ecological Statistics - The paper proposes a new perspective in the environmental and resource economics literature by examining innovation (measured by R&amp;D expenditures),...  相似文献   
240.
Jaafar  Hadi  Ahmad  Farah  Holtmeier  Lauren  King-Okumu  Caroline 《Ambio》2020,49(6):1179-1193
Ambio - The Syrian crisis caused a massive influx of displaced people into neighboring countries, with Lebanon hosting the highest per capita number of refugees (3:10). Water remains the most...  相似文献   
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