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Status and evaluation of the selected soil nutrients irrigated by unconventional water (Case study: Qom) Full text
2016
Arast, Mina | Zehtabian, Gholamreza | Jafari, Mohammad | Khosravi, Hassan | Jabalbarezi, Bahareh
Population’s exponential growth along with drought has increased water resources limitation, especially in arid and semi-arid area. Therefore, the use of non-conventional water is an important tool for water resource management. If unconventional water has no negative impact on soil properties and water, it can be used for irrigation coupled with desertification projects. So, this paper tries to present the effect of irrigation with municipal wastewater, salt water, brackish water, and combination of salty water and wastewater on some soil properties including nitrogen, phosphorus, and potassium in Qom plain. Soil samples were taken from agricultural land treated by wastewater, saline water, brackish water, combination of salty water, and wastewater and range land as control in five treatments from depths of 0-30 and 60-90 centimeter. The results showed that wastewater has increased the amount of N, P, and K to other treatments and control area. The concentration of potassium in surface layer of area treated by combination of salty water and wastewater with amount of 459.39 ppm has the most significant difference to control and other treatments. Also, the maximum amount of nitrogen was observed in sub layer of saline and brackish water treatment with amount of 0.08 percent.
Show more [+] Less [-]Challenges and developments of bioretention facilities in treating urban stormwater runoff; A review Full text
2016
Takaijudin, Husna | Ab Ghani, Aminuddin | Zakaria, Nor Azazi
Bioretention or rain garden is a preferable low impact development (LID) approach due to its characteristics which reflect natural water cycle processes. However, this system is still little understood and quite complicated in terms of design and implementation due to many technical considerations. Hence, this paper gives a review of the challenges and developments for the use of bioretention facilities to enhance its capabilities in attenuating peak flow and treating stormwater runoff particularly in urban areas. This paper reviews the main aspects of bioretention which are stormwater hydrologic, hydraulic and treatment performance. Some of the limitations during the implementation of this natural approach are highlighted in design configuration and the public perception towards this new approach. It is concluded that the bioretention approach is one of the sustainable solutions for stormwater management that can be applied either for individual systems or regional systems.
Show more [+] Less [-]Nutrient uptake rate and removal efficiency of Vetiveria zizanioides in contaminated waters Full text
2015
Akbarzadeh, Abbas | Jamshidi, Shervin | Vakhshouri, Maryam
This research compares the performance of floating systems planted with Vetiveria zizanioides as a hydroponic approach for removing nutrients from two contaminated waters. For this purpose, two pilots with overall net volume of 60 litres were constructed and inoculated by secondary treated domestic wastewater (STDW) and irrigation water obtained from Minab reservoir (IWMR) in batch mode. Regarding the experimental results, the total nitrogen removal efficiency reaches more than 40 and 75%, in two and four days’ detention time, respectively, while these figures are 75 and 85% for phosphorus. The comparative statistical analyses verify that the results reveal significant differences in nitrogen removal, its uptake and the shoots’ dry weight. Conversely, phosphorus removal, its uptake and the roots’ growth are not significantly different. The regression analysis shows that the nitrogen uptake is well correlated with the shoots’ expansion rate as a matter of substrate type. The decay coefficient rates of nitrogen and phosphorus are calculated as 0.43 and 0.52 day-1, respectively. It is then concluded that this system should be used for wastewater treatment rather than for surface water purification. However, it can be recommended as an environmental friendly approach for both, because of the high efficiency in nutrients’ removal and the aeration capability.
Show more [+] Less [-]Estimation of groundwater level using a hybrid genetic algorithm-neural network Full text
2015
Hosseini, Ziba | Nakhaie, Mohammad
In this paper, we present an application of evolved neural networks using a real coded genetic algorithm for simulations of monthly groundwater levels in a coastal aquifer located in the Shabestar Plain, Iran. After initializing the model with groundwater elevations observed at a given time, the developed hybrid genetic algorithm-back propagation (GA-BP) should be able to reproduce groundwater level variations using the external input variables, including rainfall, average discharge, temperature, evaporation and annual time series. To achieve this purpose, the hybrid GA-BP algorithm is first calibrated on a training dataset to perform monthly predictions of future groundwater levels using past observed groundwater levels and additional inputs. Simulations are then produced on another data set by iteratively feeding back the predicted groundwater levels, along with real external data. This modelling algorithm has been compared with the individual back propagation model (ANN-BP), which demonstrates the capability of the hybrid GA-BP model. The later provides better results in estimation of groundwater levels compared to the individual one. The study suggests that such a network can be used as a viable alternative to physical-based models in order to simulate the responses of the aquifer under plausible future scenarios, or to reconstruct long periods of missing observations provided past data for the influencing variables is available.
Show more [+] Less [-]Evaluating the geochemistry of Bam salt dome in Hormozgan Province, Iran Full text
2015
Asadpour, Gholamabbas
Evaluation of the geochemistry and hydrochemical quality of Bam salt dome located in southern Iran, was conducted in this study. Two composite samples from salt units were collected and analysed by XRD and XRF to determine their mineral and elemental compositions. Water samples were also collected from the only spring in the area and analysed for major anions, cations and some toxic elements. The results indicated halite as the major mineral present, while quartz, anhydrite and dolomite were present at minor levels. The presence of anhydrite and dolomite together with quartz had negative effects on edible salt quality. The dominant water type in the area was sodium-chloride. Negligible sulphate and calcium contents may be attributed to anhydrites detected in the geological texture of the study area. According to a Schoeller diagram, the water is not suitable for drinking. Concentrations of toxic metals in the salt sample were significantly higher than those in water samples. Such a result can be viewed as an opportunity to produce edible salts from the evaporation of spring water.
Show more [+] Less [-]Evaluating the consequences of the new standards on noise conditions in ships Full text
2015
Bouzón, Rebeca | Costa, Angel M | Roshan, Gholamreza | Orosa, J.A.
Noise is one of the main parameters to be considered to achieve a healthy indoor ambience in ferries. Therefore, the noise standards need to be more specialized and specifically based on real sampled data and case studies. In the present research, the noise levels in a ship, under different working conditions, were sampled and compared with those specified in the new and old standards. An initial study showed two main noise sources- clients and main engine- that influence other indoor environments, reducing the quality of life on board. The real-time data revealed that the maximum noise level limits set by the International Maritime Organization (IMO) in the older Resolution A.468 (XII) was mostly respected, except in areas where maintenance of the noise level was difficult, owing to the continuous influx of people, especially at the time of boarding and disembarking of the passengers and at the food self-service areas. In this sense, under the new Resolution MSC.337 (91), the maximum noise level allowed in the accommodation has been reduced by 5 dB (A), but this environment does not meet the standard. More results show that future standards must not only consider the noise level in a working place and add another variable, such as, the number of working hours, to obtain a representative equivalent energy, and they must also consider that a simple modification of this standard implies a redesign of most of the indoor ambiences onboard.
Show more [+] Less [-]Spectrophotometer-based student education program on health hazard assessment due to Cr(VI) and Pb contamination in surface and groundwaters of Hyderabad City, India Full text
2015
Das Sharma, Mala | Juyal, Archana | Karuna, Mantha | Das Sharma, Subrata
A student-centric research education program with the active participation of undergraduate students is initiated. The aim is to imbibe ―responsible citizenship behavior‖ in them so that each member becomes conscious and well trained to take up environmental-related issues and challenges for long-term sustainability of the ecosystem. In this work, we report spectrophotometer-based estimation of hexavalent chromium (57-268 gL-1) and lead (34–158 gL-1) concentrations in different surface waters and groundwater samples in and around the city of Hyderabad, India. Our results indicate that the studied surface water bodies and aquifers are contaminated to variable degrees and pose a serious threat to the ecosystem. In view of low geochemical baseline values for chromium and lead, the origin of heavy metal pollution is inferred to be anthropogenic, mainly originating from industrial effluents. The toxicological data are integrated with health data for risk assessment and impending health hazard. Finally, the novelty of this student-centric research program is highlighted.
Show more [+] Less [-]Collection and recycle bin location-allocation problem in solid waste management: A review Full text
2015
Purkayastha, Debasree | Majumder, Mrinmoy | Chakrabarti, Sumanta
This comprehensive work explores the research performed inoptimization of the collection bin and in recycle bin location-allocation issues in solidwaste management. Although the collection phase of solid waste management accountsfor a significant proportion of the municipal budget, it has attracted only limitedattention of the researchers. Optimization of the collection bin and recycle bin location-allocation problems in solid waste management can be advantageous with respect to binaccess to every individual person of municipality, reduction in the numbers of opendumping yards, considerable profit if the recycled products are properly processed, andas an effort toward sustainable and green world. Hence, the topic of interest should bepursued, especially in developing countries, to enable development of a cost-efficient and sustainable solid waste management system.
Show more [+] Less [-]Studies on removal of Zinc and Chromium from aqueous solutions using water Hyacinth Full text
2015
Swarnalatha, K. | Radhakrishnan, Bindhu
Phytoremediation is an eco-friendly method for removal of pollutants, which can be relied upon as a sustainable technology, if implemented under optimum conditions of plant growth. The effectiveness of water hyacinth, a topical weed, for the removal of Zinc (Zn) and Chromium (Cr) ions from aqueous solutions has been presented in this article. The potential of this plant in removing metals by phytoremediation was explored under various environmental factors such as pH, salinity, metal concentrations, available nutrients, and so on. The efficiency of metal removal was observed by varying the different parameters. It was found that the maximum removal of metals occurred at a neutral pH, low amount of salinity, lower metal ion concentrations, and lack of nutrients. The stress induced in a plant by metal absorption was visible from the health and growth pattern of the plants. The stress on water hyacinth due to metals was also assessed, by observing the changes in its chlorophyll and protein content.
Show more [+] Less [-]Comparison of the environmental indicators of phosphorus efficiency and the balance between saffron and wheat production systems in the Qaenat region, Iran Full text
2015
Yaeghoubi, Fatemeh | Jami Al-Ahmadi, Majid | Bakhshi, Mohammad Reza | Sayyari-Zahan, Mohammad Hassan
Improving the resource use efficiency in agro- ecosystems is an importantfactor for reducing environmental pollution. To evaluate phosphorus (P) efficiency andbalance indicators, research was conducted in wheat and saffron production systems inthe Qaenat region (South Khorasan Province, Iran) during 2011 and 2012, based on themethod of the Organization for Economic Co-operation and Development (OECD). Therequired information about wheat and saffron cultivation was collected via questionnairesand the required coefficients were obtained from various literatures. The results showedthat the phosphorus efficiency and balance indicators were significantly different betweendistinct districts only in the case of wheat crops. The highest P efficiencies of wheat andsaffron farms were 7.21% and 2.93%, respectively. Additionally, P efficiency andbalance indicators showed a significant difference between both crops in some districts,so that wheat had higher P efficiency than saffron, which was mainly because of thedifferent amounts of animal manure applied to these crops. There was no significantdifference between the different ages of saffron farms for P efficiency and balance.Furthermore, there was a significant negative correlation between P efficiency andbalance indicators. It would appear that there are many opportunities for improving theefficiency of P and to prevent environmental pollution through the optimization ofmanagement decisions.
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