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Spatio-Temporal Variation of an Aquifer Salinity in a Semi-Arid Area, Case Study of Sarvestan Plain, Iran Texte intégral
2022
Rasti, Moslem | Nasrabadi, Touraj | Ardestani, Mojtaba
The aim of this study is to determine the amount of quantitative and qualitative changes in groundwater in the Sarvestan plain in south of Fars province, which is one of the critical plains in Iran in terms of water resources. In this research, zoning maps of electrical conductivity of water in GIS were prepared and various hydrochemical diagrams were illustrated. Different quality parameters of water resources were compared according to the statistical data collected and the experiments performed at the beginning of the 8-year period of the research. Chemical analysis of water samples shows that the groundwater type of most of the studied wells at the beginning of the period (2013) has changed from Ca-Cl and Mg-Cl types to Na-Cl type at end of the time period (2020). Determining the trend of chemical changes shows that the diversity of water samples in terms of anions and cations in water with increasing salinity at the end of the period is less than the variety of samples at the beginning of the period. According to the results of chemical experiments, evaporation, crystallization, and weathering of rocks are the factors that control the composition of groundwater in the study area. This study shows increasing the salinity of groundwater in addition to decreasing precipitation and high water use for agricultural application, due to the type of geological formations, especially the presence of salt domes at groundwater inlets to the plain on the east side of the study area.
Afficher plus [+] Moins [-]Environmental Performance of Alternative Schiff Bases Synthesis Routes: A Proposal for CO2 Storages Texte intégral
2022
Yaseen, Anahed A. | Yousif, Emad | Al‐Tikrity, Emaad T. B. | Kadhom, Mohammed | Yusop, Muhammad R. | Ahmed, Dina S.
The increased consumption of fossil fuels provokes high levels of carbon dioxide (CO2) emissions, which give rise to serious environmental issues. Accordingly, designing and utilizing new classes of materials, such as Schiff bases, to capture CO2 gained significant attention from researchers worldwide. In the present work, two Schiff bases were synthesized and examined as storage materials for carbon dioxide gas. The prepared compounds were obtained by reacting trimethoprim with two aldehydes severally (benzaldehyde and parabromobenzaldehyde) in boiling methanol. The surface morphology of the compounds was investigated via field emission scanning electron microscopy (FESEM). The Brunauer-Emmett-Teller (BET) test showed that Schiff bases 1 and 2 have surface areas of 17.993 and 2.732 m2/g, pore volumes of 0.008 and 0.005 cm3/g, and pore diameters of 17.02 and 74.89 nm, respectively. Reasonable uptake values of CO2 (31.36 cm3/g, 6.2 wt%) and (25.30 cm3/g, 5.0 wt%) were achieved by the prepared Schiff bases 1 and 2, respectively, at 313 K temperature and 40 bars pressure.
Afficher plus [+] Moins [-]Temporal Analysis and Forecast of Surface Air Temperature: case study in Colombia Texte intégral
2022
Romero Leiton, Jhoana Patricia | Torres, Diego | Romero, Manuel
In this work, we study the short-term dynamics of the Surface Air Temperature (SAT) using data obtained from a meteorological station in Bogotá from 2009 to 2019 and using time series. The data that we used correspond to the monthly mean of the historical registers of SAT and three pollutants. A descriptive analysis of the data follows. Then, some predictions are obtained from two different approaches: (i) a univariate analysis of SAT through a SARIMA model, which shows a good fit; and (ii) a multivariate analysis of SAT and pollutants using a SVAR model. Suitable transformations were first applied on the original dataset to work with stationary time series. Subsequently, A SARIMA model and a VAR(2) with its associated SVAR model are estimated. Furthermore, we obtain one-year forecasts for the logarithm of SAT in both models. Our forecasts simulate the natural fluctuation of SAT, presenting peaks and valleys in months when SAT is high and low, respectively. The SVAR model allows us to identify certain shocks that affect the instant relationships among variables. These relations were studied by the impulse-response function and the VAR model variance decomposition. Although the statistical methods used in this study are classical, they continue being widely used in the environmental field, presenting god fits, and the results obtained in this study are consistent with environmental theories.
Afficher plus [+] Moins [-]Evaluation of Efficiency of Iron Oxide Nanoparticles (Fe3O4@CNT) in Removal of Malathion in Aqueous Medium Using Response Surface Methodology (RSM) Texte intégral
2022
Eskandarimakvand, Malektaj | Sabzalipour, Sima | Cheraghi, Mahboobeh | Orak, Neda
Organophosphates are one of the most common pesticides in the world. Among them, one can find malathion that is classified as carcinogenesis, and, as a result, should be appropriately removed since it is highly consumed and possesses a lot of pathogenicity. So far, several processes have been used to remove malathion from aqueous media. The present study investigates its removal by means of Fe3O4 iron oxide nanoparticles. Based on experimental-laboratory studies, using the Response Surface Methodology (RSM), the impact of independent variables such as pH, iron oxide nanoparticle concentration, and contact time on malathion removal efficiency have been investigated. Results show that the pH of the solution is the most important and effective parameter in the process. Optimal conditions of malathion removal based on the appropriate model, obtained from RSM, include 0.4 g/L iron oxide nanoparticles, pH of about 5 (acidic conditions), and contact time of about 1 h with ultraviolet radiation being equal to 82% malathion removal. The process, used in this study, can remove malathion from aqueous solutions according to the so-called conditions, and changing the laboratory conditions can effectively remove it. This process can also be recommended as an economic and scientific method to remove malathion from drinking water.
Afficher plus [+] Moins [-]A New Sustainable Approach to Integrated Solid Waste Management in Shiraz, Iran Texte intégral
2022
Molayzahedi, Seyed Mohammadali | Abdoli, Mohammad Ali
Cities in developing countries like Shiraz in Iran face significant challenges due to a lack of an integrated solid waste management system. Climate change, soil, and water pollution are examples of environmental issues caused by improper Municipal Solid Waste Management Systems (MSWMS) in developing countries. The aim of this study is to find solutions for these environmental problems based on the experiences of developed countries. The data was collected using several methods such as visual observations, studying accessible documents of the current situation of the MSWMS in Shiraz, and participating in an interview with engineers the 'Shiraz Municipality Waste Management Organization' (SMWMO). Results present the current functional elements of MSWMS in Shiraz, Shiraz waste diversion rate (0.22), and its Zero Waste Index (.015). Moreover, the results present some recommendations to find a way to transform cities like Shiraz into zero-waste cities. Results indicate that establishing zero-waste policies, legal frameworks, and financial strategies as well as convincing private sector involvements in installing waste-to-energy facilities and a proper sanitary landfill to move the city toward optimum recycling and zero landfilling in addition to reducing consumption and maximizing diversion rate and finally sustainable development by the cooperation of government, NGOs and media programs would solve many problems of the MSWMS and would solve environmental issues in many cities.
Afficher plus [+] Moins [-]Efficacy of Natural Coagulants in Treating Sugar Industry Effluents Texte intégral
2022
Garika, Nihanth Soury | Dwarapureddi, Bhavya Kavitha | Karnena, Manoj Kumar | Dash, Swathi | Raj, Aman | Saritha, Vara
Industrial sector is understood to be one of the major offenders in polluting environment particularlywater among others. Sugar industry is one among the agro-based industry releasing high organicpollutants rich in BOD. Though conventional treatment methods have been employed in treating sugarindustry effluents at varied degrees, they come with their own setbacks. In this direction naturalcoagulants are explored and evaluated for their potential and efficiency towards treating sugar industryeffluents. The process of coagulation and flocculation removes impurities precisely colloidalimpurities through the phenomenon of destabilization, bridging and sweep coagulation. In order tohave an effective treatment factors governing coagulation are to be optimized to determine the dose,pH, mixing time etc. The prime objective of the present study is to characterize the sugar industryeffluents, test the efficiency of both chemical and natural coagulants to treat these effluents and bringout a comparison and potential of natural coagulants with that of chemical coagulants. Jar testapparatus was employed all coagulation studies and the results were promising with reduction inparameters like colour (99.28%), electrical conductivity (60.39%), turbidity (97.67%), chloride(69.23%) and total dissolved solids (60.42%) highest by ferric chloride followed by the naturalcoagulants. The findings of the study suggest that the lowest dose of 0.25g/l was optimum to removethe physico-chemical parameters both by chemical and natural coagulants and since natural coagulantswere equally competent with chemical coagulants these can be substituted towards achieving greentreatment options.
Afficher plus [+] Moins [-]Temporal Monitoring and Effect of Precipitation on the Quality of Leachate from the Greater Casablanca Landfill in Morocco Texte intégral
2022
Zaki, Khadija | Karhat, Youness | El Falaki, Khadija
A monthly temporal monitoring of the physico-chemical parameters of the leachate from the Greater Casablanca “Mediouna” open-air landfill in Morocco over a period of 13 months was carried out to show their variability over time. This monitoring also highlights the effect of rainfall on leachate quality through fluctuations observed in wet and dry periods. Indeed, the leachate was sampled from a collector that drains a mixture of young and mature leachate. Several physico-chemical parameters were studied: pH, temperature, conductivity, organic matter (BOD5 and COD), total matter (TS, TVS), nitrogen (N-NO2-, N-NO3-, N-NH4+, TKN), total phosphorus (Tp), salts (Cl-, SO42-) and metals (Cd, Co, Cr, Ca, Cu, Fe, K, Mg, Mn, Ni, Pb, Zn). As a result, significant concentrations were recorded throughout the monitoring for the majority of the parameters, showing a high aggressiveness of the leachate. Also, statistically significant relationships were observed between the different parameters. On the other hand, the leachate pollution index (LPI) was calculated to determine the overall potential of leachate pollution. The identification and study of the behaviour of the physico-chemical parameters is very useful for the design of an adequate leachate treatment plant for the Greater Casablanca landfill "Mediouna", taking into consideration the extreme values recorded during the monitoring period, in order to avoid any malfunctioning due to an underestimation of the pollution.
Afficher plus [+] Moins [-]Distribution Features of Microplastic Particles in the Bolshiye Koty Bay (Lake Baikal, Russia) in Winter Texte intégral
2022
Karnaukhov, Dmitry | Biritskaya, Sofya | Dolinskaya, Ekaterina | Teplykh, Maria | Ermolaeva, Yana | Pushnica, Victoria | Bukhaeva, Lidiya | Kuznetsova, Iya | Okholina, Anastasia | Silow, Eugene
The problem of pollution of aquatic ecosystems with microplastics has been actively studied by the world scientific community. Most of this research has been devoted to marine ecosystems, whereas scant research has been conducted on fresh water bodies. Lake Baikal (Russia) is a unique natural reservoir. Previous studies devoted to the amount of microplastics in the waters of Lake Baikal were carried out singularly and were not of a systemic character; therefore, previously obtained data does not reflect a complete picture of the state of the lake. Within the framework of this study, our goal was to study the composition and morphological structure of microplastic particles in the ice of Lake Baikal at different distances from the coastline. To do this, a number of ice samples were taken from the upper and lower sides at five different points in South Baikal opposite the village of Bolshiye Koty. Later these samples were analyzed for the types of microplastics and their amount. In the samples taken, two types of microplastics were found—fragments and fibers—with fibers being predominant. The median values of the number of microplastics particles are higher in samples taken at the interface between water and ice, compared to samples taken from the ice surface. Presumably, main part of microplastic fibers found opposite the village of Bolshiye Koty were brought in by a constant circular current from the opposite east coast. In turn, the low number of fragments in the samples may be due to the freezing of the coastline.
Afficher plus [+] Moins [-]Assessment of Urban Growth and Variation of Aerosol Optical Depth in Faridabad District, Haryana, India Texte intégral
2022
Ranjan, Kumar | Sharma, Vipasha | Ghosh, Swagata
Sustainable urbanization under sustainable development goals requires quantitative information on urban landscape. Despite having the fastest growth of urban area and poor air quality, Faridabad, a constituent district of National Capital Region, fails to gain much research attention. Present study based on multi-temporal; freely available satellite image has indicated 3% increase in the built-up against 2% decrease arable land from 2008 to 2018. Further, spatial metrics (Shanon’s entropy, class area (CA), number of patches (NP), largest patch index (LPI)) has indicated scattered development of built-up. Increase CA (11470 ha in 2008 and 13806 ha in 2018) and NP (221 in 2008 and 476 in 2018) have indicated isolated development of built-up with small area coverage. Increase in LPI (12.5% in 2008 and 13.5% in 2018) of built up indicated compact growth of dense built-up in the southern and eastern side leading to the vertical expansion of the city area. Linear expansion of the residential built-up, industrial, and commercial area along the highways, roads and railways and vehicular emission has contributed to the high aerosol concentration. While, in the rural region the high aerosol loading has also been observed because of the extensive use of fertilizer and stubble burning. Present research on land-use land cover changes and its impact on air quality could be contributed significantly in urban policy making for climate change adaptation and mitigation strategies.
Afficher plus [+] Moins [-]Analysis of Surface Water Quality using Multivariate Statistical Approaches: A case study in Ca Mau Peninsula, Vietnam Texte intégral
2022
Giao, Nguyen Thanh
The study was conducted to assess surface water quality in Ca Mau peninsula using multivariate statistical analysis. Fifty-one water samples with the parameters of pH, dissolved oxygen (DO), total suspended solids (TSS), biochemical oxygen demand (BOD5), chemical oxygen demand (COD), ammonium (N-NH4+), orthophosphate (P-PO43-) and total coliform were used in the evaluation. Water quality is assessed using national standard and water quality index (WQI). The methods of cluster (CA), discriminant (DA), principal component analysis (PCA) were used to analyze the variation patterns of water quality. The surface water was contaminated with organic matters, suspended solids, nutrients, and microorganisms. DA revealed that DO, TSS, BOD5 and pH contributed 76.91% to the seasonal variation of water quality. Water quality is classified from bad to heavily polluted. CA grouped water quality into 7 clusters and DO, TSS, BOD5, COD and coliform of the clusters 1-3 were significantly higher than those of the clusters 4-7. PCA presented that PC1-PC3 was the main sources affecting water quality, explaining 85.45% of the variation in water quality. The sources of pollution can be human (domestic wastewater, waste from agriculture, fisheries, industry, landfills), natural (hydrological regime, rainwater overflow, river bank erosion). pH, DO, BOD5, COD, TSS, N-NH4+, P-PO43- and coliform have an impact on water quality and need to be continuously monitored. However, for the multivariate statistical method to be more effective, an initial data set with several water quality parameters sampling locations is needed. The current results provide scientific information and support local water quality monitoring activities.
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