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641.
Ali  Qaisar  Yaacob  Hakimah  Parveen  Shazia  Zaini  Zaki 《The Environmentalist》2021,41(4):616-632
Environment Systems and Decisions - Regardless of known as environment-friendly entities, Islamic banks indirectly impact the environment through their clients’ engagement and slow response...  相似文献   
642.
Environmental and Ecological Statistics - The availability of a variety of Global Climate Models (GCMs) has increased the importance of the selection of suitable GCMs for impact assessment studies....  相似文献   
643.
Environmental Geochemistry and Health - Micronutrients deficiency in soil–plant and human is well-addressed; however, little is known about their spatial distribution, magnitude of deficiency...  相似文献   
644.

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).

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645.
Assisted phytoremediation has been widely used for decontamination of potentially toxic elements contaminated soils. A greenhouse experiment was conducted to evaluate the effectiveness of different microbial inoculations and surfactant levels on the phytoremediation of a Pb-polluted calcareous soil by maize. The results showed that application of surfactant increased both root and shoot dry matter yields. Microbial inoculations, however, had no significant effect on the root or shoot dry matter yield. Mean Pb uptake in maize root or shoot increased only following the application of some surfactant levels. Inoculation with microorganisms significantly increased both mean Pb concentration and uptake in maize root but not in maize shoot. Application of 4?mmol surfactant kg?1 along with inoculation with Priformospora indica was effective in increasing Pb phytostabilisation potential. While the application of 2?mmol surfactant kg?1 along with inoculation with Pseudomonas fluorescens was effective in increasing Pb phytoextraction potential. The fact that the values of translocation efficiencies were low in all treatments, demonstrated the low capability of maize for translocation of Pb from root to shoot. Inoculation with P. fluorescens was the most effective treatment in increasing metal micronutrient uptake. Microbial inoculation and surfactant levels enhanced Pb phytoremediation mostly through phytostabilisation of this metal by maize.  相似文献   
646.
The term ‘heavy metals’ is commonly used in the environmental literature to refer to metals and metalloids associated with environmental pollution, toxicity and adverse effects on biota. The term has been diversely defined, mostly in terms of density, relative atomic mass and atomic number. This diversity of definitions has raised questions about the nomenclature of these elements. The inclusion of the metalloid As and the nonmetal Se with heavy metals is also an important issue. Some people have called the term as meaningless, imprecise and poorly defined and have suggested abandoning the use of the term. The term itself may not be problematic but the careless and inconsistent use of terminology has led to a confusion about the meaning of the term. The use of the term may be continued but it should be defined in a more comprehensive and scientific way. Here, a more comprehensive definition of the term ‘heavy metals’ is suggested as ‘naturally occurring metals having atomic number (Z) greater than 20 and an elemental density greater than 5 g cm?3.’ A screening of the Periodic Table according to this definition yields 51 elements to be called ‘heavy metals.’ As and Se are excluded from heavy metals.  相似文献   
647.
Variations in geo-environmental attributes differ strongly from those of urban anthropogenic structures. Similarly, these types of structures are self-directed and arranged and prone to abrupt process-related changes and modifications. Thus, there are many reasons why planned urbanization forms in association with disturbances in ecosystem mobility. The current research highlights these variations in the context of social–cultural assessments within the Jhelum River watershed, which strongly expresses urbanization structure development mechanisms. The climate ranges from semi-arid to subhumid subtropical and sub-mountainous climate, though the extreme temperatures may rise as high as 49.4°C in June and may drop as low as ?1.6°C in January. The rainfall is low in the southwest and gradually increases towards the northeast, whereas the Salt Range is the major topographic feature that controls climatic impacts and promotes sustainable development. Cross-disciplinary methods are adopted in this investigation to assess the social–ecological landscape system (SELS) in terms of its mobility and degree of urbanization. The Sustainable Development Goals of the 2030 Agenda recognize that human livelihoods and the management of natural resources cannot be addressed separately. Investing in the sustainability of mountain communities and ecosystem conservation and protection will provide benefits for humanity as a whole. It pertains to the commensurate development of the SELS and its response to interruptions. Thus, a reliable SWOT analysis for management approaches is introduced that may enable the development of competencies that promote and lead towards rapid improvements in the sustainability of retrograde urban infrastructure, including watersheds.  相似文献   
648.
A 3D hydrodynamic model has been applied to the Curonian Lagoon to study the pollution impact of E. coli on a new beach that might be opened in the lagoon. Through a field survey the E. coli inputs were measured and then used in the numerical model, and through laboratory experiments the decay rate of E. coli was established. The model has been calibrated and validated for the year 2015, and several scenarios have been studied, such as sewage system breakdown, severe weather conditions or high river loads. The model has then been run for a period of 12 years to obtain a robust statistics for the pollution on the planned beach. Results show that the decay rate of E. coli is between 0.55 days and 2.3 days and the modeled decay times are compatible with these numbers. The only scenario that would create a risk for the bathing waters of the beach is a breakdown of the sewage system on the Curonian Spit. In this case the hours (and days) over legally allowable bathing threshold were computed in order to estimate the number of days the beach could be closed. These results have been confirmed by the 12 year simulations. With an influence map analysis the two most critical sewage systems could be identified.  相似文献   
649.
Photocatalytically-oxidized cross-linked chitosan-glutaraldehyde (CS-GLA) was obtained via irradiation of a simple assemblage of an immobilized layer-by-layer TiO2/CS-GLA system on a glass plate with a 45-W fluorescent lamp. The oxidation process was observed to occur only in the presence of oxygen and TiO2 within 5 cycles (10 h) of irradiation. Characterizations studies of the oxidized cross-linked polymer involving swelling index, pH-potentiometric titration and ionic conductivity measurements, as well as CHN, FTIR, 13C solid-state NMR,UV–Vis DRS and photoluminescence spectroscopy analyses generally indicated that the oxidation led to the formation of carbonyl groups, partial elimination of some un-reacted amino groups and change of visual color to be more brown without altering much of the whole molecular structure of the CS-GLA. This study also indicated that the photocatalytic performance of TiO2/oxidized CS-GLA system was higher than both TiO2/CS-GLA system and TiO2 single layer for the removal of phenol. Moreover, the adsorption effect was extremely negligible and the photodegradation of phenol was mainly due to the photocatalytic process.  相似文献   
650.
Sorption of metal ions by soil and clay minerals is a complex process involving different mechanisms, and controlled by different variables that can interact. The aim of this work was to study the retention mechanisms of Pb ions on different soil samples. Surface soils were sampled from Guilan and Hamadan provinces in north and northwest of Iran with temperate and semiarid climates. The adsorption isotherms of Pb on the soils have been studied at 15, 27 and 37°C. The adsorption data for different soils were fitted into Langmuir and Freundlich models. Temperate soil samples had higher clay content, cation exchange capacity, dichromate (oxidable) organic carbon, total Kjeldahl-nitrogen, biological activity, amorphous and crystalline Fe and Al, but semiarid soil samples had higher sand content, pH, equivalent calcium carbonate, available P and K. Lead adsorption data obtained from semiarid soils against those obtained from temperate soils were better fitted in both Langmuir and Freundlich models. Langmuir constants Q 0 for Pb adsorption in semiarid soils were considerably lower than those for Pb adsorption in temperate soils. However, the binding energy (K L) of Pb and Freundlich constant n were higher for data of semiarid soils. The effect of temperature on the Pb adsorption was positive especially in temperate soils; however, soil properties had higher effects on Pb adsorption.  相似文献   
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