In India, festivals like Ganesh Chaturthi, Durga Puja form an integral part of its rich and diverse cultural heritage. The ritual of idol worshipping and immersion into water bodies signifies the cycle of creation and dissolution, acknowledging the rhythm of nature that all things come from nature and go seamlessly back to it for a cycle to begin. But, in recent times the practice of immersing Plaster of Paris (POP) made idols along with other decorative material into natural water bodies has immensely raised the severe issue of water pollution and creating an uncongenial aquatic ecosystem. In this purview, a pilot project for chemical disintegration of POP idols during Ganesh festival was run in Bhopal, Madhya Pradesh, India to study the effective application of a chemical method developed by CSIR-NCL, Pune by using ammonium bicarbonate. Water samples were collected before and after idol immersion activity from the tank. The detailed chemical analysis of the aqueous phase was carried out to study the effect on various parameters and application of residues. The analytical results reveal that the method has its practical utility as both the products of the reaction can further be used in chalk making and as fertiliser with dilution. The concentration of heavy metals was found minimal and in the limits in the treated aqueous phase. This paper also supports the sustainable management of such functions rather than the use of artificial materials.

The considerable increase in the amount of nitrogen in the surface water is a major environmental problem. It has become a great matter of worry because of the multiple environmental effects including eutrophication and health risks. The El-Kebir West watershed is a coastal plain in northeastern Algeria.This study aims to determine the physicochemical quality of waters of the western WadiEl-Kebir and its main tributariesand also to evaluate the spatiotemporal variabilityof its physicochemical quality in particular of mineral nitrogen during wet and dry periods. Four sampling campaigns were realized as follows: January 2015 and February 2016 corresponding to water high season and in March and September 2016 corresponding to the low season. The water samples were obtained from the seven stations located along western Wadi El-Kebir. Temperature, pH,conductivity,dissolved oxygen,SO42-, PO43-, NO3-, NO2-and NH4+ were measured either in situ or in the laboratory.A statistical treatment employingthe PCA method (The Principal Components Analysis) was applied for all the obtained results. It has been noticed that the S2 and S3 upstream stations are very rich in ammonium (NH4+) at the low water period with average values of 15.22 mg/L and 20.41 mg/L, respectively.This study has shown the influence of seasonal variations and anthropogenic activities on the evolution of physicochemical settings, in general, and on mineral nitrogen in particular. In conclusion,the waters of Wadi El-Kebir were of an average to poor quality.

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.

Rajasthan generates 1055 million litres per day as wastewater, out of which 27 million litres is treated and nearly 1028 million litres untreated wastewater is discharged in various water resources. The present study is based on the impact of Kota stone or limestone mining on water resources. Among those villages and census towns, experiencing mining activity, a total of 26 surface water and groundwater samples were tested and analysed. Mining waste often creates eutrophication, toxification, temporary hardness and sometimes permanent hardness. The mining belt was 17.54 km2 in the year 2000 which further increased to 24.25 km2 in the year 2018. The parameters analysed were pH, EC, TDS, alkalinity, total hardness, calcium and magnesium hardness, DO, COD, chloride, sodium and potassium. The predictive mapping for the mining belt was executed in Arc GIS software using Inverse Distance Weightage (IDW) method. The mean of pH was 9.13, TDS 457.12 mg/L, total hardness 593.52 mg/L, calcium hardness is 205.54 mg/L, magnesium hardness 387.53 mg/L, COD 442.2 mg/L, Na+ 139.9 mg/L, K+ 19.40 mg/L, Cl- 318.29, DO 3.04mg/L and alkalinity 14.02 mg/L.

This study applied the Soil and Water Assessment Tool (SWAT) to the Shanxi Reservoir watershed, a drinking water source in Zhejiang Province, China. The important sources of non-point source pollution (NPS) in Shanxi reservoir watershed are agricultural fertilizer application, domestic sewage and livestock breeding, this brings new challenges to water source management. The simulated runoff and water quality parameters total nitrogen (TN) were compared to those of the observed values in the watershed. The Nash-Suttcliffe efficiency (NSE) was 0.94 for monthly runoff during the calibration period 2007-2010, and 0.84 during the validation period 2011-2012. The model can well satisfy the simulation of runoff. For monthly TN of Sancha water quality monitoring station, the NSE is 0.7 in the calibration period of March 2009 to April 2011, and 0.75 in the verification period of May 2011 to December 2012. For the Jiujiang water quality monitoring station, the model index parameters are slightly lower than Sancha, but it is also very good for water quality simulation. The four parameters of total nitrogen, organic nitrogen (ORGN), nitrate-nitrogen (NO3-N) and ammonia nitrogen (NH4-N) were used to analyse the nitrogen pollution of Shanxi Reservoir watershed. The multi-year monthly average results of nitrogen pollutant loadings show significant differences, with large fluctuations every month. ORGN and NH4-N showed a consistent trend, showing a steady growth trend from January to June, peaking in August and continuing to decline in other months, and NO3-N peaked in March. The pollution load of TN in Shanxi reservoir watershed ranged from 142.27 kg/km2 to 725.31 kg/km2, showing a large spatial difference. The pollution load of the tributary basin is weaker than that of the main stream, which generally shows an increasing trend from upstream to downstream. Overall, the pollutant load is consistent with land use and agricultural production and living conditions, showing typical characteristics of non-point source pollution. Through the establishment of regional nitrogen pollution model and the study of pollutant distribution characteristics, this study puts forward some suggestions for controlling the nitrogen pollution load of the Shanxi Reservoir watershed, optimizes the agricultural planting mode, and intercepts the pollution sources that are not directly discharged into the water body.