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61.
Environmental Science and Pollution Research - Aquaculture is one of the fastest-growing industries in the world, and its prominent role has been proven in supplying food for the growing world...  相似文献   
62.
Despite extensive research on microplastics (MP) in marine environments, little is known about MP abundance and transport in terrestrial systems. There is, therefore, still little understanding of the main mechanisms driving the substantial transport of MP across different environmental compartments. Storm events can transport MP beyond boundaries, such as from the land to groundwater or the ocean, as has already been discovered for organic carbon transport. Urban stormwater detention ponds are suitable environments to study the impact of stormwater on the environmental fate and transport of MP. Herein, we investigate the longitudinal and vertical distribution of MP within two detention ponds with different physical characteristics. Soil samples were collected at various locations and from multiple depths (surface and subsurface layers) for measuring MP concentrations using fluorescence microscopy. Our findings show that MP are retained more near the inlet of the ponds, and MP of larger sizes were found more abundantly near inlets than outlets. We also found that MP mass and sizes decrease from surface soil to subsurface soil. In the pond, where vegetation (grass root network) was more considerable, MP were found more evenly distributed along the depth. In terms of shape, the fragments were the most abundant MP shape.  相似文献   
63.
In this study, the volume and the cash value of water loss, and reduction of water loss as a result of enforcement action during 2011–2013 in the drinking water network of villages in Kermanshah Province, Iran, have been investigated. Date collected by referring to the different parts of rural water and waste water company of Kermanshah Province and checklist were completed. The study showed the volume of produced water and sold water has increased and the water loss percentage has decreased. High cost of water production compared to revenue of sold water and water loss resulted in significant detriments in terms of the water production costs. Water loss level decreased from 33% to 30% as result of measures taken to reduce water loss but, it is still 15% higher than the world average level. Also the reduction in number of water resources and increase in the number and volume of reservoirs indicates a lack of water and a growing need. As result of high water loss, waste of costs in the contrast of water production cost and also because physical water loss accounts for most of the water loss of villages, necessary measures can be effective in reducing loss and have economic justification.  相似文献   
64.
Modeling the distribution patterns of species is a generally efficient tool to assess their ecological characteristics. In this study, we compared ecological niche factor analysis (ENFA) and maximum entropy (Maxent) techniques to predict the most suitable distribution range of Rana macrocnemis. The Maxent model predicted potential suitable habitats for R. macrocnemis with high success rates (AUC Training data = 0.877 ± 0.039). According to the map constructed, three important variables had high contribution to species presence: temperature (50.4%), land cover (24.6%) and elevation (14.4%) variables. The ENFA results were relatively similar to Maxent jackknife analysis. The results implied that R. macrocnemis prefers grassland and needle leaf deciduous forest with high elevations, and low temperature.  相似文献   
65.
66.
Environment, Development and Sustainability - In this research, a new method to determine the supply chain performance based on its sustainable strategies is proposed. This method consists of a...  相似文献   
67.
Introduction. Based on the literature, the ergonomic saddle chair provides the most appropriate posture for users. Determination of the seat height is critical to establish the proper posture, carried out using various methods of anthropometry. This study aimed to develop a simple and applied method for determining the saddle seat height with an emphasis on appropriate posture. Methods. In this study, anthropometric dimensions including weight, body height, popliteal height and seat height at 135° knee angle in 150 male and female dentists were measured. In the laboratory, to determine the ‘acetabuloischial number’, 25 male and female natural hip bones were measured. The mean saddle-chair height with knee angle of 135° was then compared by two different methods, field measurement and the new calculation method. Results. The results showed a strong correlation between data gathered from the two different methods, the field measurement and the new calculation method (98%), and Cronbach’s α from the intraclass correlation was equal to 0.994 (p?<?0.05). This indicated that the two methods produced similar results. Conclusion. The new method can be applied to calculate the optimal height of the saddle seat based on body height and popliteal height.  相似文献   
68.
In order to achieve sustainable development in agriculture, it is necessary to quantify and compare the energy, economic, and environmental aspects of products. This paper studied the energy, economic, and greenhouse gas (GHG) emission patterns in broiler chicken farms in the Alborz province of Iran. We studied the effect of the broiler farm size as different production systems on the energy, economic, and environmental indices. Energy use efficiency (EUE) and benefit-cost ratio (BCR) were 0.16 and 1.11, respectively. Diesel fuel and feed contributed the most in total energy inputs, while feed and chicks were the most important inputs in economic analysis. GHG emission calculations showed that production of 1000 birds produces 19.13 t CO2-eq and feed had the highest share in total GHG emission. Total GHG emissions based on different functional units were 8.5 t CO2-eq per t of carcass and 6.83 kg CO2-eq per kg live weight. Results of farm size effect on EUE revealed that large farms had better energy management. For BCR, there was no significant difference between farms. Lower total GHG emissions were reported for large farms, caused by better management of inputs and fewer bird losses. Large farms with more investment had more efficient equipment, resulting in a decrease of the input consumption. In view of our study, it is recommended to support the small-scale broiler industry by providing subsidies to promote the use of high-efficiency equipment. To decrease the amount of energy usage and GHG emissions, replacing heaters (which use diesel fuel) with natural gas heaters can be considered. In addition to the above recommendations, the use of energy saving light bulbs may reduce broiler farm electricity consumption.  相似文献   
69.
Traditional and indigenous knowledge on plants usage is a valuable source of information from cultural and natural perspectives, reflecting society’s complicated and close relationship with the environment. Communities have a valuable source of traditional knowledge on the utilization of natural resources, and it is worth to be documented and preserved for current and future applications. We conducted this research to collect and identify plant species of Karvan District and document the traditional knowledge on their use and consumption values. Regarding the results, 150 plant species are used by local communities, more than 30 % of which are directly consumed as food, 24 % (37 species) are used as medicinal plants, and 16.3 % are applied for decoration purposes; 58.6 % of the species are consumed in the raw form, and the remaining is processed before consumption. Leaves (35 %), seeds (21 %) and flowers (21 %) are the most frequent parts of the plants that are used. High number of young emigrants to industrialized areas in seek of job opportunities is threatening this precious source of indigenous knowledge. Attempts to preserve this empirical source of information by encouraging trans-generational knowledge transmission would help to maintain it for future applications.  相似文献   
70.
Among the methods that are being developed to date for CO2 capture and separation, carbon dioxide adsorption is of great interest due to its low energy consumption, low equipment cost and easiness for application. In this work, a simple method which is easier than existing approaches requiring more complicated and longer computations is presented to accurately predict the carbon dioxide adsorption isotherms for a microporous material as a function of temperature and partial pressure of carbon dioxide. The method appears promising and can be extended for CO2 capture as well as for separation of wide range of adsorbents and microporous materials including several molecular sieves merely by the quick readjustment of tuned coefficients. The proposed method showed consistently accurate results across the proposed pressure and temperature ranges. Predictions showed an average absolute deviation of 1.4% compared to existing Sips and Langmuir equations which show an average absolute deviations of 2.3% and 4%, respectively. The proposed method is superior owing to its accuracy and clear numerical background, wherein the relevant coefficients can be retuned quickly for various cases. This simple-to-use approach can be of immense practical value for the engineers and scientists to have a quick check on adsorption capacities of a given adsorbent at various temperatures and pressures without the necessity of any experimental measurements. In particular, personnel dealing with regulatory bodies of greenhouse gas control and process industries would find the proposed approach to be user friendly involving transparent calculations with no complex expressions.  相似文献   
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