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Forecasting and Seasonal Investigation of PM10 Concentration Trend: a Time Series and Trend Analysis Study in Tehran 全文
2023
Pardakhti, Alireza | Baheeraei, Hosein | Dehhaghi, Sam
In this study, a multitude of statistical tools were used to examine PM10 concentration trends and their seasonal behavior from 2015 to 2021 in Tehran. The results of the integrated analysis have led to a better understanding of current PM10 trends which may be useful for future management policies. The Kruskal – Wallis test indicated the significant impact of atmospheric phenomena on the seasonal fluctuations of PM10. The seasonal decomposition of PM10 time series was conducted for better analysis of trends and seasonal oscillations. The seasonal Mann-Kendall test illustrated the significant possibility of a monotonic seasonal trend of PM10 (p = 0.026) while showing its negative slope simultaneously (Sen = -1.496). The forecasting procedure of PM10 until 2024 comprised 15 time series models which were validated by means of 8 statistical criteria. The model validation results indicated that ARIMA (0,1,2) was the most satisfactory case for predicting the future trend of PM10. This model estimated the concentration of PM10 to reach approximately 79.04 (µg/m3) by the end of 2023 with a 95% confidence interval of 51.38 – 107.42 (µg/m3). Overall, it was concluded that the use of the aforementioned analytical tools may help decision-makers gain a better insight into future forecasts of ambient airborne particulate matter.
显示更多 [+] 显示较少 [-]Status, Health Effects and Remediation Techniques of E-waste – A Review 全文
2023
Guin, Shailu | Deswal, Surinder
The annual global generation of e-waste is estimated to be 59.08 million tonnes (7.37 kg per capita), out of which the major chunk is being processed in informal sector using primitive and hazardous methods in developing countries due to cheap labour, less stringent laws and regulatory policies. Despite the fact the annual global value of e-waste industry being about USD 62.5 billion that provides employment to millions in developing countries, the unstructured/informal operations in e-waste sector had and have been causing hazardous health issues in human and environment along with unlawful activities. Many studies have been reported on wide array of interrelated aspects and issues of e-waste, but only few studies have reviewed potential remediation techniques that can take care of the increasing e-waste and its sustainable management. Therefore, disposal and remediation techniques for polluted sites have been the key concerns in the field of environmentally sustainable management (ESM) of e-waste. The present review revealed that of all the classic and hybrid remediation techniques, the biological remediation techniques being eco-friendly and cost effective needs to be explored for metal removing from contaminated environment. The review also concludes the imminent necessity of ESM by framing and implementing regulations and laws essentially incorporating Extended Producer Responsibility (EPR) in developing countries. The review of Indian scenario suggests the scope of startups for the sustainable recycling of e-waste to achieve healthy environment, employment and economic opportunities.
显示更多 [+] 显示较少 [-]Treatment of Fish Processing Wastewater by Alum and PAM: A Comparative Study on Turbidity, COD, BOD, and Rheological Properties 全文
2023
AL Riyami, Hanan Ahmed Said | Al Dawery, Salam Kadhim | Reddy, Sreedhar | Ahmed, Anwar
This research article compares the efficacy of using alum and poly aluminum chloride (PAM) for the treatment of fish processing wastewater. This study aims to determine the effectiveness of each treatment method in reducing turbidity, COD), BOD, and altering the rheological properties of the wastewater. Batch mode coagulation and flocculation experiments were conducted using lab scale jar test apparatus. The findings indicate that both alum and PAM can significantly reduce turbidity and COD. The highest turbidity removal efficiency of 93% was achieved with alum at a dose of 200 mg/L, while PAM achieved a maximum turbidity removal efficiency of 86% at a dose of 100 mg/L. Alum and PAM achieved the highest BOD5 and COD removal efficiencies at a dosage of 200 mg/L and pH 7.0. However, the removal efficiencies varied at different pH values and dosages. Alum and PAM have significant effect on the rheological properties of fish processing wastewater. The viscosity of settled residual sludge after chemical coagulation is more compared to untreated fish processing wastewater due to aggregation of suspended particles to form larger flocs. This would improve the settling properties of the coagulated sludge. The study concludes that both alum and PAM can be viable options for treating fish processing wastewater, with Alum showing a slight edge over PAM in certain aspects.
显示更多 [+] 显示较少 [-]Catalytic Conversion of Carbon Dioxide by Metal-Organic Frameworks: an Effective Approach for CO2 Utilization 全文
2023
Tayebi, Leila | Rahimi, Rahmatollah | Akbarzadeh, Ali Reza
Due to the increase in carbon dioxide emission, there is a need for achieving efficient ways to reduce CO2 harmful effects. There are several strategies to mitigate atmospheric CO2 concentration. The catalytic cycloaddition of carbon dioxide with epoxides to provide cyclic carbonates employing metal-organic frameworks is a promising method for this purpose. Herein the application of two porous porphyrinic MOFs (Co-PMOF and Cu-PMOF) as catalysts in CO2 conversion was investigated. These MOFs demonstrated good crystallinity and porosity, providing them with two promising platforms to study CO2 conversion reactions. These heterogeneous porphyrin-based MOFs are catalytically efficient towards the chemical conversion of CO2 under moderate conditions because these MOF matrices contain a high density of active Lewis acidic and basic sites for activating CO2 and epoxide compounds. These MOFs exhibited high catalytic efficiency for the chemical fixation of CO2 at ambient temperature and solvent-free conditions. The reactions formed the proportionate cyclic carbonates in good yields. These products are valuable compounds in a variety of chemical fields.
显示更多 [+] 显示较少 [-]A Preliminary Study on the Water Quality from two Estuaries in Madura Island, East Java, Indonesia 全文
2023
Fitrihidajati, Herlina | Purnomo, Tarzan | Rachmadiarti, Fida | Ambarwati, Reni | Yolanda, Rofiza
The water quality in the western part of Madura Island is currently faced with a severe threat due to pollution. Therefore, this study aimed to investigate the water quality from Bancaran and Kwanyar estuaries, Madura Island, using the physicochemical approaches. A total of eight physiochemical parameters such as salinity, temperature, pH, DO, CO2, BOD, Pb, and Cd were investigated at three sampling stations of each estuary on 15 June 2022 and 19 December 2022 to identify the potential environmental factors controlling the water quality for effective monitoring and management of these estuaries. The results showed that temperature (25–29.5ºC), pH (7.47–7.8), DO (2.45–4.57 ppm), CO2 (0.5–10.4 ppm), BOD (1.86–9.99 mg.L-1) and Pb (–0.55 to –0.31 mg.L-1) differed significantly (P < 0.01), while salinity (0.2–2.90‰) and Cd (0.02–0.05 mg.L-1) did not exhibit significant differences (P > 0.05). Pearson’s correlation indicated significant positive correlations between salinity and Pb, as well as Cd and Pb. According to the principal component analysis (PCA), salinity and BOD were related to the Kwanyar estuary, while the other parameters were associated with the Bancaran estuary. This preliminary investigation showed a decline in the water quality of these estuaries, specifically from DO measurement. Although low DO levels occur naturally, the continuous occurrence will affect the living organisms in the water that plays an important role in the aquatic environment. Therefore, continuous monitoring of these estuaries is needed to provide better information and for protection as well as sustainable use of water resources.
显示更多 [+] 显示较少 [-]Origin of Heavy Metals amongst Nuisance Dust-Fall Particles in Western Iran 全文
2023
Rajabi, Mahdi | Souri, Bubak
The purpose of this study was to evaluated the origin of the heavy metals amongst nuisance dust particles in Sanandaj, Khorrmabad and Andimeshk cities located in different latitudes in western Iran for the dustiest year during last decade. Samples of dust-fall particles were collected with 10 days intervals from these three cities for the duration of June 2012 to July 2013 using Deposit Gauge Method. Concentration of the heavy metals including iron, manganese, zinc, copper, arsenic, chromium, silver, nickel, lead and cadmium were measured using atomic absorption spectroscopy. The Quantification of Contamination index (QC) was applied to evaluate the origin of heavy metals among dust-fall particles collected in three stations. The results revealed that the annual mean rate of dust-fall was 1.73, 2.66 and 3.37 g/m2 per 10 days for Sanandaj, Khorramabad and Andimeshk, respectively. The highest and the lowest amount of dust-fall were obtained for July and February, respectively, while Fe had the highest concentration among the metals studied. The temperature and wind speed were found to be the most correlated meteorological parameters to dust-fall content throughout the three stations. According to QC index; Ag, Cu, Cd, As, Pb, Mn and Zn (except Pb and Mn for Andimeshk) were derived mainly from similar origins such as anthropogenic activities but the increased values of Fe, Ni, and Cr were ascribed to natural processes. Furthermore, Cu had the highest correlation with other heavy metals measured and was determined the most stable metal amongst dust-fall particles for the three studied stations.
显示更多 [+] 显示较少 [-]Sustainable Energy Transition for Cities Based on Long-Term Planning Supported by a Fuzzy Cognitive Map 全文
2023
Eftekhar, Alireza | Yazdanpanah Dero, Qiuomars | Zaker Esfehani, Alireza
The present study was aims to explore resilience and transformation capabilities and explore their applicability in the field of energy. It focuses especially on the role of the cognitions of stakeholders and decision-makers in the uptake and management of sustainability transitions. Fuzzy cognitive mapping (FCM) is used to aggregate different stakeholders’ views on the functioning and performance of the urban energy system of the city of Tehran. In the case of Tehran, the urban energy network is analyzed in terms of resilience and transformability by studying the degree of connectivity and its influence on both system characteristics. Three scenarios of policy options are simulated to weight their outcomes in terms of sustainability, Scenario A: Optimization of economic incentives; Scenario B: Strong education and awareness campaigns; and Scenario C: Stronger local institutional initiatives. Scenario A shows a potential perverse effect if the current economic structure is maintained, even if the economic crisis is overcome. Combining Scenarios B and C provides the best results in terms of sustainability. This suggests that successful transformation in cities should pivot on a combination of top-down and bottom-up actions to unlock resilient but unsustainable states, and that special care needs to be taken when managing highly connected and/or influential elements of the system, as contextual dependencies might hinder the agency of change, particularly in the context of cities. Network characteristics, such as connectivity, can be useful indicators to inform resilience and transformation management, although the double-edge sword nature of connectivity should be noted.
显示更多 [+] 显示较少 [-]Review of Phytoremediation for Arsenic-Contaminated Soils: Mechanisms and Challenges 全文
2023
Soltanian, Mehdi | Salmak, Saba | Shahriari, Toktam
Environmental pollution has become and increasing concern due to growing risk to human health. Soil pollution is an aspect of environmental pollution that has received comparatively less attention than water pollution. However, considering direct effects of contaminants transmission through ingestion to the human body, it can lead to greater risks for human health. Arsenic is a highly prevalent environmental pollutant, and considerable number of people worldwide suffer from constant exposure to it. While there are several ways to manage and remediate contaminated soils, phytoremediation has been paid special attention due to its higher social acceptability and lower cost. Nevertheless, this approach faces challenges, including effectively handling significant quantities of contaminated biomass, managing it appropriately, and selecting suitable plant species for the remediation process. In this regard, numerous endeavors have been undertaken to tackle these obstacles like strategies encompass the utilization of amendments, adept management of biomass, and the implementation of hybrid remediation approaches. This study aims to review prior research on mechanisms, challenges, and enhanced phytoremediation of arsenic-contaminated soils, encompassing reduction of contaminated biomass after phytoremediation.
显示更多 [+] 显示较少 [-]Tetracyclines uptake from irrigation water by vegetables: Accumulation and antimicrobial resistance risks 全文
2023
Gudda, Fredrick | Odinga, E.S. | Tang, L. | Waigi, M.G. | Wang, J. | Abdalmegeed, D. | Gao, Y.
Wastewater irrigation may introduce antibiotic residues in the soil-plant systems. This study aimed to investigate the uptake of tetracyclines by spinach and collard greens and assess associated ecological and human health risks. Synthetic wastewater spiked with 1 ppm and 10 ppm of oxytetracycline, doxycycline, and tetracycline was used to grow vegetables in a greenhouse pot experiment. The uptake and accumulation of the tetracyclines were low and residual concentrations in the soil were negligible. All the tetracyclines were detected at concentrations ranging from 1.68 to 51.41 μg/g (spinach) and 1.94–30.95 μg/g (collard greens). The accumulation rate was in a dose-response scenario with a bioconcentration factor of 6.34 mL/kg (spinach) and 2.64 mL/kg (collard greens). Oxytetracycline had the highest accumulation in leaves, followed by doxycycline and tetracycline, and the residual concentrations followed the same order. The highest residual concentration was in soils receiving 10 ppm oxytetracycline. Residual concentrations in the soil were lower than accumulated levels and exerted negligible ecological risks. Tetracyclines accumulation in spinach significantly differed between the vegetables demonstrating a subspecies difference in uptake and accumulation. Ecological risk quotient (RQ) and human health risk quotient (HQ) were below thresholds that would exert toxicity and resistance selection impacts. Although RQs and HQs are low (<0.1), this study shows that the vegetables accumulate tetracyclines from irrigation water, posing plausible human health risks to allergic individuals. Similarly, the ecological risks cannot be ignored because the synergistic and antagonistic effects of sublethal concentrations can perturb ecosystem processes.
显示更多 [+] 显示较少 [-]Do soil and water conservation practices influence crop productivity and household welfare? Evidence from rural Nigeria 全文
2023
Ogunniyi, A.I. | Omotayo, A.O. | Olagunju, K.O. | Motunrayo, O. | Awotide, B.A. | Mavrotas, G. | Aremu, A.O.
Do soil and water conservation practices influence crop productivity and household welfare? Evidence from rural Nigeria 全文
2023
Ogunniyi, A.I. | Omotayo, A.O. | Olagunju, K.O. | Motunrayo, O. | Awotide, B.A. | Mavrotas, G. | Aremu, A.O.
One of the most serious challenges threatening agricultural sustainability in Nigeria is land degradation. Although this issue has received little attention, soil and water conservation practices have been identified as a possible pathway out of the potential problems posed by land degradation. Therefore, the central research question that this paper tries to address is the following: Do adoption of soil and water conservation (SWC) practices affect crop productivity and household welfare? This paper uses data collected by the International Institute of Tropical Agriculture (IITA) from maize farmers in rural Nigeria. We usedemploy the propensity score matching (PSM), inverse probability weighting adjusted regression model (IPWRA) approach, and the linear regression with endogenous treatment effect (LRETE) model to incorporate the typologies of SWC practices, and tested how the model affects crop productivity and household welfare. Additionally, multinomial logit was used to estimate the factors influencing the decision to adopt single and multiple SWC practices. The estimates show that education, age of the household head, access to credit, experience of drought, soil fertility, and occupational stress contribute to the decision to adopt SWC practices. The casual effect estimates reveal that both single and multiple adoptions of SWC practices had a positive and significant relationship with the crop productivity and welfare of the adopters. The results show that the adoption of combined SWC practices has a higher impact on crop productivity and welfare than single SWC practices. For instance, the adoption of a combination of three SWC practices was found to increase crop productivity and household welfare by 27.55% and 38.23%, respectively versus 13.91% and 15.11% in the case of single SWC practices. The study suggests that profile-raising agenda and efforts that focus on promoting the adoption of combination of SWC practices should be designed and implemented to enhance crop productivity and hence the welfare of the maize farming households in rural Nigeria.
显示更多 [+] 显示较少 [-]Do soil and water conservation practices influence crop productivity and household welfare? Evidence from rural Nigeria 全文
2023
Ogunniyi, Adebayo Isaiah; Omotayo, Abiodun Olusola; Olagunju, Kehinde Oluseyi; Motunrayo, Olyeyemi; Awotide, Bola Amoke; Mavrotas, George; Oladapo, Adeyemi
PR | IFPRI3; ISI; CRP3.2; 4 Transforming Agricultural and Rural Economies | Development Strategies and Governance (DSG); Transformation Strategies | CGIAR Research Program on Maize (MAIZE)
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