Iron-based waterworks sludge was activated using 0.5-3 mol/L H2SO4 acid to obtain the acid-activated iron-based waterworks sludge (AAIBWS). The sludge treated with 1 mol/L H2SO4 acid was best for phosphorus adsorption and used to carry out batch phosphorus adsorption experiments. The influencing factors including solution pH, contact time and reaction temperature were investigated. The results indicated that the acid environment was favourable for P adsorption. The phosphorus adsorption increased with the rising reaction time and temperature. The pseudo-second-order equation was best to describe the adsorption process among the three kinetic models. The Langmuir isotherm provided a better fit of the data than the Freundlich model. Thermodynamic parameters showed that the phosphorus adsorption on AAIBWS-1 had a spontaneous and endothermic nature.

This paper includes a cradle-to-gate life cycle impact evaluation of gasoline blends in India. The potential environmental impacts of gasoline blends with three major components, i.e., methanol, ethanol, and n-butanol are assessed. The production of methanol from the natural gas reforming process, ethanol from hydrogenation with nitric acid, and n-butanol from the oxo process are considered in the current study. The results show that the gasoline blending with methanol has the lowest impact (11 categories) and is nearly constant from 5 to 15%. For gasoline with ethanol as an additive, the global warming potential, ozone depletion potential, and abiotic depletion potential rise with increasing ethanol addition. Meanwhile, increasing ethanol addition reduces the acidification potential and terrestric ecotoxicity potential impact of gasoline blends. Similarly, gasoline with n-butanol as an additive has higher acidification potential, eutrophication potential, human toxicity potential, terrestric ecotoxicity potential, marine aquatic ecotoxicity potential, and photochemical ozone creation potential compared to methanol and ethanol.

Ugii Lake is a freshwater lake located in the steppe region of Mongolia and is an important breeding and staging area for a wide variety of waterfowl. Remote sensing and geographic information system techniques were used to estimate fluctuations in the surface area and water balance of Ugii Lake. To estimate the changes in lake water balance, lake water fluctuations should be analyzed using the most accurate methods. A different water extraction technique was applied, and the results were compared with field surveys conducted in May, July, and September 2020. The lake surface area using both NDWI and MNDWI-1 showed a strong, positive correlation (R=0.93, R=0.94, p < 0.01) with the water level of Ugii Lake. A topographic map of Ugii Lake was provided by the project (P2018-3568) conducted in August 2019 and used to estimate the volume of Ugii Lake in ArcGIS 10.1. This result was consistent with that of a previous study by JICA in 2005. Finally, the water balance of Ugii Lake was estimated, and the results proved that the influence of both surface and groundwater on Ugii Lake are valuable parameters, which are completely dependent on hydrological regime changes mostly due to local climate change in steppe regions. This study provides valuable insight into the most suitable water extraction methods for lakes in semi-arid steppe regions in Mongolia.

A large quantity of trace metals has been continuously polluting the environment as a result of increasing urbanization and industrial processes. In 2016-2017, the metal (Cd, Cu, Cr, Ni, Pb, and Zn) levels were determined in fecal pellets of Blue Rock Pigeon (Columba livia) at Bais Godam (industrial location) in Jaipur and Chittora (rural location) in Rajasthan, India. Fecal pellets in industrial regions which are under higher anthropogenic influence exhibited higher metal concentrations when compared with the fecal pellets of the same species in rural area which have minimal anthropogenic input, with statistically significant industrial-rural differences in the metal concentrations except for Ni. Results obtained in this study, as well as the comparison with literature data, indicated that concentrations of Cr and Cu were high in fecal pellets of Blue Rock Pigeon in the industrial region of the present study. Furthermore, many significant correlations were also observed between metal levels in the industrial region which could be attributed to a similar source. Moreover, contamination levels of pigeon excrement serve as one of the most compelling indicators in terrestrial systems for the monitoring of metal pollution levels.

Biodiesel has been receiving increasing attention because of its fuel properties and compatibility with petroleum-based diesel fuel. Therefore, it is necessary to measure the engine performance and exhaust emissions of engines using petroleum-based diesel fuel and biodiesel blends. The main goal of this study is to investigate the capability of several machine learning (ML) techniques including artificial neural network (ANN), adaptive neuro-fuzzy inference system (ANFIS), general regression neural network (GRNN), radial basis function (RBFN), and support vector regression (SVR) for predicting performance and exhaust emissions of the diesel engine fuelled with biodiesel blends. The case application is a Hyundai D4CB 2.5 engine together with B0, B10 and B20 biodiesel blends which are popularly used in Vietnam. The engine process parameters are used as inputs and the outputs include predicted torque and NOx emission. Different predicting models based on ML techniques are developed and validated. The performance of each model is evaluated and compared using root mean squared error (RMSE), mean absolute percentage error (MAPE), mean absolute error (MAE), and correlation coefficient (R). The obtained results indicate that SVR can be used to develop the model for the prediction of performance and exhaust emissions. The study also provides a better understanding of the effects of engine process parameters on performance and exhaust emissions.

Exploration was conducted in the study area of Coimbatore district by collecting 60 samples from the agricultural belt. The groundwater is neutral to alkaline in character with pH varying from 6.70 to 9.02 among the mean of 7.37. Elevated electrical conductivity (EC) was observed in upstream parts of the study area. Water quality for irrigation is determined by several key components like electrical conductivity (EC), total suspended solids (TDS), residual sodium carbonate (RSC), chloro alkali Indices (CA I & CAII), sodium adsorption ratio (SAR), percent sodium (%Na), Kelley’s ratio (KR), magnesium hazard (MH), permeability index (PI) and soluble sodium percent (SSP). In total, six samples were found to be with high salinity hazard. The mean value of SAR was found to be 5.24, maximum sample falls under C2S1 to C4S1 category as per USSL Salinity diagram. As per Piper diagram in the anionic regime, Cl dominates HCO3-, CO32- and SO42-. Higher magnesium hazard in the groundwater is owing to the consequence of dyeing and bleaching industries. Magnesium hazard value indicates that 51 samples out of 60 are unsuitable for irrigation. According to the study, it is revealed that groundwater in the study area is contaminated by both natural factors and anthropogenic activities.

Soil pollution is a worldwide problem caused by both natural and anthropogenic activities. This has resulted in health and physiological problems to both plants and animals. This study investigated heavy metals in soils within the immediate vicinity. Soils from Seven APIIC zones in Visakhapatnam were collected and analysed for physicochemical characteristics and heavy metals. The data obtained were subjected to the pollution index model and multivariate statistical analysis. The data obtained showed that the soils are rich in zinc, and heavy metals are above trace level with a minor positively skewed distribution. The analysis of pollution index, geoaccumulation index and ecological risk factors in soils in all the locations showed that they are mainly contaminated and polluted by Cd followed by Zn. The mean heavy metal concentrations around APIIC can be arranged in increasing order as Cr < Co < Pb < Cu < Cd < Zn. Element pairs such as Zn-Pb, Zn-Cu, Zn-Cd, Pb-Cu, Pb-Cd, Cu-Cr, Cd-Co and Cr-Co showed strong positive correlation coefficient “r” indicating their association in the study area. The observed concentrations of heavy metals revealed that soil contamination has been increasing and measures must be taken to ensure the adoption of more environment-friendly practices.

To explore the impact of the fishing moratorium on fish stocks, some parameters and environmental factors were monitored downstream of Gezhouba Dam in April, June and August of 2013. Fish density and target length were get using hydro-acoustics (DIDSON). The results indicated that the fish density distributions in April, June and August were significantly different. The fish density decreased with time but kept a level that was close and steady in April and June. The average fish density of April was significantly greater than that in August (P<0.05). The percentage of fish target length distribution was consistent in time and space. In the study, the hydraulic and environmental factors were not the main reasons for the decrease of fish density and target body length in the spatial and temporal scale. Overfishing was the main cause and the fishing moratorium was substantially effective for keeping the sustainability of the fish resources in the adjacent areas of Gezhouba Dam.

The essential issues solved by geoenvironmental engineers relate to the assurance of uncontaminated regions of the subsurface just as the remediation of locales of the subsurface that have been sullied by releasing waste materials, spilling over the ground and underground stockpiling tanks and penetration of pesticides. In city areas, garbage and waste materials are generally dumped into landfills. A landfill site, which is otherwise called a trash dump, is used for the disposal of waste materials by burial. A safe landfill is a deliberately built sorrow in the ground into which wastes are put. The principal objective is to stay away from any water driven association between the wastes and the surrounding environment especially groundwater. This paper discusses landfill, in terms of its construction, stability and failure. The analysis and modelling of the landfill failure occurred in different countries like Poland, Turkey, Israel, the Philippines, China and Sri Lanka which are discussed.

Wenyu River is the “mother river” in Beijing. In recent years, the research on the water quality of the Wenyu River has increased gradually. In this paper, the monitoring data at Shahe Reservoir, Lu Tuan Gate, Xin Bao Gate, and Ma Fang sections for each month in 2019 were adopted. The single-factor evaluation method and the comprehensive pollution index method were selected to analyze the current situation of the water quality of Wenyu River in the Chang Ping section and its temporal and spatial variation trend. The single factor evaluation method showed that the dissolved oxygen exceeded the standard seriously in all other months of the year except that the situation was better in May, June, and July. The ammonia nitrogen content reached the highest level in January, followed by a month-by-month decreasing trend. After June, each section basically met the requirements of Class v water quality. The comprehensive pollution index method shows that the water quality of Shahe reservoir varies greatly throughout the year, and it is in grade v for 6 months. The evaluation results of both methods show that the water quality of all sections of Wenyu River in 2019 was mostly in category v.