Arsenic removal methods for drinking water in the developing countries: technological developments and research needs

Arsenic pollution of drinking water is a concern, particularly in the developing countries. Removal of arsenic from drinking water is strongly recommended. Despite the availability of efficient technologies for arsenic removal, the small and rural communities in the developing countries are not capable of employing most of these technologies due to their high cost and technical complexity. There is a need for the “low-cost” and “easy to use” technologies to protect the humans in the arsenic affected developing countries. In this study, arsenic removal technologies were summarized and the low-cost technologies were reviewed. The advantages and disadvantages of these technologies were identified and their scopes of applications and improvements were investigated. The costs were compared in context to the capacity of the low-income populations in the developing countries. Finally, future research directions were proposed to protect the low-income populations in the developing countries.     

Spatio-temporal analysis of climatic variables in the western part of Bangladesh

Monitoring and detecting trends of climatic variables like rainfall and temperature are essential for agricultural developments in the context of climate change. The present study has detected trends in annual and cropping seasonal rainfall and temperature data for the period of 1961–2011 using Mann–Kendall (MK) test, Spearman’s rho (SR) test and modified Mann–Kendall test that has been applied to the significant lag-1 serial correlated time series data, and slope has been estimated using Sen’s Slope estimator for twelve meteorological stations located in the western part of Bangladesh covering about 41 % of the country. Almost 71 % trends explored by MK test in annual rainfall are statistically insignificant, and SR test also complies it. The spatial distribution of rainfall trend shows insignificant positive trends in major part of the area. Significant positive trends both by MK test and by SR test at 95 % confidence levels are observed at rates of 8.56, 11.15 and 13.66 mm/year at Dinajpur, Rangpur and Khepupara stations, respectively, and the Kharif season rainfall of these stations also shows significant increasing trends except Dinajpur. On the other hand, significant decreasing trends in annual rainfall are found at Bhola (?11.67 mm/year) and Rajshahi (?5.951 mm/year) stations and decreasing trends in rainfall dominated the Pre-Kharif season over the area. But, 83.33 % of the stations show rising trends in annual mean temperature with significant positive trends (as observed by both MK test and SR test) at Rangpur, Bogra, Faridpur, Jessore and Bhola stations where the rate of changes vary from 0.013 °C/year at Faridpur to 0.08 °C/year at Bhola. Most of the trends in Rabi and Pre-Kharif seasons of mean temperatures are not statistically significant. However, all stations except Barisal show significant rising trends in temperature in Kharif season. To cope with this changing pattern of rainfall and temperature, effective adaptation strategies should be taken to keep up the agricultural production that is related to livelihood of the most people and to ensure the country’s food security.     

Assessment of environmental impact on air quality by cement industry and mitigating measures: a case study

In this study, environmental impact on air quality was evaluated for a typical Cement Industry in Nigeria. The air pollutants in the atmosphere around the cement plant and neighbouring settlements were determined using appropriate sampling techniques. Atmospheric dust and CO₂ were prevalent pollutants during the sampling period; their concentrations were recorded to be in the range of 249–3,745 mg/m³ and 2,440–2,600 mg/m³, respectively. Besides atmospheric dust and CO₂, the air pollutants such as NO _x , SO _x and CO were in trace concentrations, below the safe limits approved by FEPA that are 0.0062–0.093 mg/m³ NO _x , 0.026 mg/m³ SO _x and 114.3 mg/m³ CO, respectively. Some cost-effective mitigating measures were recommended that include the utilisation of readily available and low-cost pozzolans material to produce blended cement, not only could energy efficiency be improved, but carbon dioxide emission could also be minimised during clinker production; and the installation of an advance high-pressure grinding rolls (clinker–roller-press process) to maximise energy efficiency to above what is obtainable from the traditional ball mills and to minimise CO₂ emission from the power plant.     

Correction to: Preparation and properties of fly ash‑based geopolymer concrete with alkaline waste water obtained from foundry sand regeneration process

Journal of Material Cycles and Waste Management - A correction to this paper has been published: https://doi.org/10.1007/s10163-021-01257-w     

Does national carbon pricing policy affect voluntary environmental disclosures? A global evidence

Environmental Economics and Policy Studies - This paper examines the relationship between institutional pressure of national carbon pricing policy and the voluntary environmental disclosures (VED)...     

Predicting impacts of major projects on housing prices in resource based towns with a case study application to Gladstone,Australia

The resources sector in Australia makes a major contribution to the national economy, and underpins employment and population in the mining and mineral processing towns. For those towns, rapid growth in employment can generate particular pressures in local housing markets because of the relatively large size of the industry and the small housing stocks involved. Through a case study of Gladstone, the study provides a dynamic five-step population and housing model, to estimate short to medium term mining impacts of major resource developments. The model includes both the direct and indirect labour force generated by new resource sector developments and their flow-on effects on population increases. Sensitivity testing has allowed for different levels of resource development, employment multipliers and labour inflows. Three different approaches have then been applied to predict the housing price impacts of the expected population growth.     

Eddy diffusivity: a single dispersion analysis of high resolution drifters in a tidal shallow estuary

In an estuary, mixing and dispersion resulting from turbulence and small scale fluctuation has strong spatio-temporal variability which cannot be resolved in conventional hydrodynamic models while some models employs parameterizations large water bodies. This paper presents small scale diffusivity estimates from high resolution drifters sampled at 10 Hz for periods of about 4 h to resolve turbulence and shear diffusivity within a tidal shallow estuary (depth <3 m). Taylor’s diffusion theorem forms the basis of a first order estimate for the diffusivity scale. Diffusivity varied between 0.001 and 0.02 m²/s during the flood tide experiment. The diffusivity showed strong dependence (R² > 0.9) on the horizontal mean velocity within the channel. Enhanced diffusivity caused by shear dispersion resulting from the interaction of large scale flow with the boundary geometries was observed. Turbulence within the shallow channel showed some similarities with the boundary layer flow which include consistency with slope of 5/3 predicted by Kolmogorov’s similarity hypothesis within the inertial subrange. The diffusivities scale locally by 4/3 power law following Okubo’s scaling and the length scale scales as 3/2 power law of the time scale. The diffusivity scaling herein suggests that the modelling of small scale mixing within tidal shallow estuaries can be approached from classical turbulence scaling upon identifying pertinent parameters.     

Dissipation pattern and risk quotients assessment of amisulbrom in Korean melon cultivated in plastic house conditions

Amisulbrom formulated as suspension concentrate was applied at the rate recommended for Korean melon to determine the dissipation pattern (at two different sites), the pre-harvest residue limit (PHRL), and risk assessments. Samples collected over 10 days were extracted using liquid-liquid extraction (LLE) and cleaned up with solid-phase extraction (SPE) Florisil cartridge. Residual concentrations were determined using liquid chromatography-ultraviolet detector (LC-UVD) and confirmed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The standard showed good instrument response linearity with a correlation coefficient (R ²) = 0.9999, and the recovery ranged from 87.5 to 93.7%. The dissipation half-life calculated from two different sites were found to be 7.0 and 8.8 days for sites 1 and 2, respectively. A PHRL graph constructed from the data indicated that if the residue levels were less than 0.55–0.59 mg/kg 3 days before harvest or less than 0.61–0.74 mg/kg 7 days before harvest, then they would be lower than the maximum residue limits (MRLs) at harvest. Risk assessments showed that the risk quotient (RQ) was 4.39–3.47% at 0 day, declined to 1.53–1.63% at 10 days. Therefore, the current data indicate that the amisulbrom can be applied safely to Korean melon; hence, it is unlikely to induce adverse health effects in consumers.