Metal oxide nanoparticles have captivated scrupulous research interest because of its major relevance in the field of medicine, catalysis, pigment, electronics, biotechnology, sensors, optical devices, adsorption, DNA labelling, drug delivery, kinetics, spintronics and piezoelectricity. Nanoparticles (NPs) became more significant for its reasonable property as a heterogeneous non-toxic catalyst with environmental reimbursement. The biogenic innovation of metal oxide NPs is an enhanced alternative owing to eco-friendliness. In the biological field, the probable efficacy of NPs has been reported by scores of scholars in the treatment of cancer. Owed to munificent returns, NPs explored as a powerful catalyst for several organic transformations. This section unlocks with a short course on to synthesize metal oxide NPs on a natural scale.

The epilithic diatoms of a periurban watercourse of Casablanca city (Bouskoura stream) were studied from samples taken in 8 stations (distributed in the upstream-downstream direction) for two years (August 2015-July 2017). The recorded diatomic flora consists of 54 species corresponding to 27 genera and belonging to 5 main families: Monoraphids, Naviculaceae, Nitzschiaceae, Araphids and Surirellaceae. This flora is predominantly alkaliphile and characterizes ?-mesosaprobe to polysaprobes and eutrophic to hypereutrophic media. Responses assemblage to natural and anthropogenic disturbances were analyzed. Diatom assemblages structure analysis shows that downstream of this watercourse, where pollution is intense, the abundances of pollosensitive taxa such as Achnanthes minutissima, Cymbella affinis are low or even nulls and we are witnessing the appearance of polysaprobe forms such as Nitzschia palea, Nitzschia capitellata and Nitzschia frustulum that tolerate rich environments in organic matter or highly polluted. Spatial variation in species diversity could not highlight changes in water quality at the prospected sites; on the other hand, the change in the percentage of pollutant-tolerant taxa (PTV) revealed the full extent of the alteration due to gradual nutrient and organic matter inputs into the Bouskoura watercourse. In addition, the correlation obtained between this index and the organic pollution index (IPO) is highly significant. Principal component analysis (PCA) highlighted taxonomic differences between stations. The results obtained in this work have emphasized the importance of diatoms as a bioindicator of the health status of this periurban watercourse.

The holy city of Ratanpur is situated in the Bilaspur district of the Central Indian state of Chhattisgarh. In the past few decades, the wetlands and water bodies of Ratanpur have been subjected to various anthropogenic pressures and undergone changes in land use land cover (LULC) patterns. The paper focuses on assessing the changes in land use and land cover in and around Ratanpur city from 1989 to 2015 using LANDSAT satellite imageries. The processing of satellite imageries and quantitative assessment of LULC data was done using ArcGIS and ERDAS Imagine software. From the current study, it is evident that the numbers and quality of ponds have decreased resulting in decreased numbers and frequency of avian fauna in the area. Earlier water bodies covered an area of 3.76% which has decreased to 2.06%. The reduction in areas covered under water bodies has increased in the dry watercourse area (3%) and river bed area (0.80%). As seen from 2015 data the built-up land areas have expanded by 2.22% as compared to 1989. A considerable decrease in open forest area (8.21%) and agricultural land (3.97%) has been witnessed, whereas the area occupied by scrubland (6.42%), wasteland (1.18%), and built-up land (1.99%) has increased. The Spatio-temporal LULC changes of the study area can be used to monitor, plan, and implement proper town and country planning to maintain the sustainable environment of Ratanpur city. The adverse impact of urban growth in the surface water bodies/ponds must be regulated by taking suitable conservation measures at the individual and community level for maintaining the biodiversity and aesthetic beauty of the area.

Amphibians grow and reproduce in water, and are sensitive to water pollution. Atrazine is one of the widely distributed herbicides that can damage the amphibians. To study the influence of atrazine on the growth, development and oxygen consumption of Pelophylax nigromaculata larvae, 26 stages of tadpoles were raised in water containing different concentrations of atrazine (0, 8, 16, 32 and 64 ?g/L). After treatments at different times (10, 15, 20, 25 d), the snout vent length (SVL), total length, body width and the bodyweight of tadpoles were measured, and oxygen consumption of tadpoles was checked with an aquatic biorespirometer. The results showed that with the increase of treatment time, the SVL, whole length, body width and the bodyweight of P. nigromaculatus tadpoles of each concentration group increased. At the same treatment time, the SVL, whole length, body width and the bodyweight of P. nigromaculatus tadpoles gradually decreased with the increase of concentration. Compared with the control group, the oxygen consumption in the treatment groups increased in the short-term treatment (10 d), had no difference in the medium-term treatment (15 d) and decreased in the long-term treatment (20 and 25 d).

Sengguruh Reservoir located in Malang Regency has important function as sediment barriers for Sutami Reservoir. The water contains many organic matters that will cause eutrophication. The effect of eutrophication can reduce biodiversity in the reservoir. The purpose of this study is to identify the trophic status of Sengguruh Reservoir using TSI method and to estimate the nutrient limit (nitrate and phosphate) to predict the eutrophication using quantile regression approach. The results show that Sengguruh Reservoir is in heavy eutrophic state. On the other hand, the nutrient limit estimation to predict heavy eutrophication is 0.853 mg/L for nitrate and 0.862 mg/L for phosphate.

Lead wastewater not only causes deterioration of water quality but also further enters the human body through the food chain and is harmful to human health. Therefore, there is an urgent need to find an economical, simple and efficient water treatment technology to treat lead-contaminated wastewater in waterbodies. In this paper, the modified biochar derived from corn straw by magnesium chloride is prepared. Adsorption experiments of Pb(II) in solution by the modified biochar are carried out. Experiment results show that the modified biochar mainly contains C and O elements, and a large number of functional groups. The adsorption amount of Pb(II) by modified biochar reaches 5.15 mg/g under 0.2 g of modified biochar, 25 mg/L initial concentration of Pb(II) ion, reaction time of 480 min, temperature 25°C and at a speed of 200 rpm. The adsorption process of Pb(II) ions in solution by the modified biochar fits on the Freundlich isotherm model. Pseudo-second order kinetic model can better describe the adsorption process of Pb(II) ion in solution by the modified biochar. The process of adsorbing Pb(II) ions in solution by modified biochar is dominated by multi-layer adsorption process and chemical adsorption process.

Present investigations utilize two-dimensional flow modelling abilities of (HEC-RAS) Hydrologic Engineering Centres River Analysis System for flood inundation mapping in the downstream area of Purna basin, exposed to recurrent flooding. Floods are natural disasters, which cause loss of life and damages to properties and nature. 2-D Hydrodynamic model is utilized to assess geomorphic viability of floods in downstream side of Purna basin. In this research study, downstream region geometry of Purna river basin, the flood plain of the study area and historical observed flood data of unsteady flow have been used to develop the 2-D hydrodynamic model. For analysis of flooding, a reach of 20 km of river situated downstream of Purna River basin has been considered. Point-by-point fundamental terrain data is taken from a Digital Elevation Model (DEM) of 30-meter resolution image and is utilized to produce the (2D) two-dimensional flow area and stream geometries. River flow information like daily discharge during rainy months, slope available along the river reach from Mahuva gauging station close to Navsari city is utilized for the unsteady flow modeling. Depth of water, velocity distribution and water surface height obtained after 2D flow simulation are utilized to decide the degree of flooding. RAS-mapper is an effective tool in HEC-RAS, which can be utilized for inundation of research area. For unsteady flow analysis, each time step was done based on inflow hydrograph using RAS mapper tool in HEC-RAS, which gives the spatial distribution of the river flow. The outcomes from this research examination can be utilized for disaster management, flood management, early warning system by authorities in addition to infrastructure growth decisions.

The association between urbanization and health at the global level, as well as the role of air pollution, has increased the interest in studies, aimed to improve the air quality of urban areas. Addressing the challenges of pollution caused by urbanization plays a crucial role in developing sustainable urbanization. Understanding the temporal characteristics of particulate matter mass concentrations with an aerodynamic diameter of less than 2.5 ?m and 10 ?m (PM2.5 and PM10) is very important to counter the effect of air pollution. We have analysed and interpreted the diurnal, monthly and seasonal variations of one-hour average PM concentrations taken from Central Pollution Control Board (CPCB) for six stations over Hyderabad, India during March 2018 to February 2020. Average concentrations of PM2.5 (41.5 ?g/m3) and PM10 (91.52 ?g/m3) for two consecutive years (2018 and 2019) are found to exceed the standard values of World Health Organization (WHO) standards (PM2.5 = 10 ?g/m3 and PM10 = 20 ?g/m3) and National Ambient Air Quality Standards (NAAQS) (PM2.5 = 40 ?g/m3 and PM10 = 60 ?g/m3). A clear diurnal and seasonal variations are observed for all the stations. In diurnal cycle, a large PM concentration was observed between 8 AM to 10 AM and again between 6 PM to 9 PM with a minimum at 3 PM in all seasons and also for all stations which clearly shows semidiurnal variations. Data analysis shows a high concentration of particulate matter in winter compared to other seasons. The PM2.5 (PM10) concentrations in winter were found to be increased by three (two times) when compared to monsoon. The ratio of PM2.5 to PM10 is very close to 0.5 during post-monsoon and winter, and 0.4 in summer and monsoon seasons, which clearly shows that PM2.5 comprises a major portion of PM10. The PM2.5 and PM10 are highly correlated with correlation coefficient 0.9. Out of 6 stations, Zoo Park is contributing more particulate matter pollutant concentrations.

In recent years, there has been an increasing interest in the possibility of the use of aluminosilicate minerals in order to maintain and improve soil productivity. The unique ion-exchange and adsorption properties of pyrophyllite minerals indicate the possibility of its application in agriculture as soil conditioner. The aim of this study was to evaluate whether the application of pyrophyllite could reduce the use of mineral fertilizers in lettuce production without adverse effects on its yield and quality. The experiment was carried out from November 2018 to April 2019 inside a polyethylene covered greenhouse in Gornji Moranjci, Bosnia and Herzegovina. The following quality parameters were analysed using standard methods: ascorbic acid content, total phenolic content, total antioxidant capacity and content of potentially toxic heavy metals (Cr, Pb, Ni, Cu, Zn and Mn) in lettuce. The results of this study showed that the substitution of fertilizers with pyrophyllite in amount of 25% and 50% of recommended fertilizer rate under experimental conditions increase lettuce yield and total antioxidant capacity compared to the control treatment, i.e. 100% recommended fertilizer rate. The results of this study also support the hypothesis that pyrophyllite could be used as remediation material in polluted soils by heavy metals. However, further investigation is necessary to confirm these hypotheses across different soil ecosystems.

In this study, a total of 50 groundwater samples from the coal-bearing aquifer in the Xinji coalfield (one sub-coalfield of the Huainan coalfield) have been collected, and their major ion concentrations have been measured for the evaluation of its suitability for drinking and irrigation, and then the mechanism controlling the water chemistry have been analysed. The results indicate that the groundwater samples are slightly alkaline with TDS higher than the freshwater (<1000 mg/L), and most of them are classified to be Cl- and HCO3- types. The groundwater samples have WQI range from 5.63 to 179 (mean = 64.9), suggesting that these samples are good for drinking. However, the results of sodium adsorption ratio and residual sodium carbonate indicate that only a few of the samples can meet the requirement of irrigation, but must be treated before application. Gibbs diagram and the relationships between major ions, as well as the factor analysis, imply that water-rock interaction is the main process controlling the groundwater chemistry, including the dissolution of evaporate minerals and the weathering of silicate minerals.