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The purpose of this paper is to assess the ground water quality and salinity issues in the fast developing coastal urban lands of two river basins of Thiruvananthapuram district, Kerala, South India.

In order to address the water quality of the basins, field sampling was conducted and the samples were analysed in the laboratory. A comparison with water quality standards was also made and the interpretations of the results were done using GIS and statistical tools.

The values of conductivity, chlorides and salinity show that the coastal areas of Neyyar and Karamana basins are severely affected by salinity intrusion in addition to the pollution problems. More than 90 per cent of the samples are with hardness lower than 100 mg/l. About 70 per cent of the study area is with calcium concentrations lower than 25 mg/l. The content of sulphate and magnesium in Poovar and Poonthura coastal stretches is found to be higher compared to other regions.

Since not much work has been published from the study area on these aspects, the hydrochemical characterization is a very important in deciphering the quality of ground water for its proper management. The water quality evaluation and salinity intrusion studies are very important for the future planning and development of this area.

Cyanide is extremely toxic to both human and aquatic life and exists as a contaminant in soils and groundwater at decommissioned gasworks sites due to past industrial practices. This included the processing and disposal of gas purification wastes which contained cyanide. The biodegradability of cyanide at gasworks sites in south‐eastern Australia is investigated to determine the viability of in situ bioremediation. Two study sites show cyanide concentrations in groundwater of up to 5,300mg/L CN (total) in the vicinty of these sites. Laboratory experiments using column microcosms indicate both aerobic and anaerobic biodegradation of cyanide in water. Rates of degradation are typically first order with degradation microbiologically driven and are not simple oxidation‐reduction reactions. The rate of degradation is variable, depending on the existence of microbes, concentration and temperature. Even though both sites have cyanide contamination, only one requires remediation. In situ bioremediation is possible at this site thus providing an acceptable outcome to both site owner and the environment.

Most fresh and good quality water resources, feasible for development and distribution, are already being used. Conflicts over water resources between bordering countries, states, counties, or sectors are a common occurrence.

Reviews trends in environmental protection and sustainability in Latvia and introduces a programme in this field at the University of Latvia in Riga. Concludes that regional changes are necessary.

The adverse effect of plastic pollution on the tourism industry is one of the emerging research areas in the field of sustainable tourism over the past years. However, there is a lack of discussion on this issue in the academic platforms. Considering this, in this chapter, a scientometric analysis of 110 academic publications from the Web of Science (WoS) between 1999 and 2021 related to plastic pollution and tourism is presented. A bibliometric analysis using CiteSpace was utilised to analyse the data to present the keyword timezone, collaboration network and co-citation network. The analysis shows that the publications in this field have increased rapidly, and it has become an emerging and interdisciplinary research topic. Scholars from Australia, Spain, Brazil and China have published most on the topic. The Chinese Academy of Science with four articles is the largest contributor in this field among other institutions. Moreover, citizen science is found to be a new keyword coming up in recent years, and human health is one of the major concerns. The findings from this study provide valuable insights for the academicians and policy makers in understanding the issue.

As population grows, industries blossom and demand for space increases, cities become the centre point for myriads of challenges for urban administrators. This chapter investigated challenges of urban development, land use changes and environmental impacts resulting from pressure on urban land. The study was primarily qualitative in nature and adopted a case study approach. The city of Ndola was selected for this purpose. Four institutions, namely, Zambia Environmental Management Agency (ZEMA), Water Resources Management Agency (WARMA), Kafubu Water and Sewerage Company (KWSC) and Ndola City Council (NCC), were used for data collection. At each institution, one official was purposively selected by management based on their knowledge and experience on the subject. The primary data were collected mainly through semi-structured questionnaires in face-to-face interviews. The chapter concludes that pressure for development land has resulted in increased demand for change of use, allocation and construction in environmentally vulnerable areas such as the Kafubu and Itawa River basins and their tributaries. This has further resulted in serious threats to the environment due to pollution of water sources from domestic and industrial waste. The chapter though argues that tools for overcoming these challenges are already provided for in the legislation, it is the implementation and effective coordination among agencies charged with planning, land allocation, water distribution and protection of the environment, such as ZEMA, WARMA, KWSC and NCC, which is lacking. Considering the foregoing, it is recommended that land and water administrative systems should be improved through among other things, effective consultation between various agencies involved in environmental management, zero tolerance to illegal land allocation and effective implementation of statutes.

Steam contamination (solid particles in the superheated steam) comes from the boiler water largely in the carry‐over of water droplets. The need for extreme purity of steam for use in high pressure turbines has prompted the development of highly satisfactory devices for separating steam and water in a boiler drum. Consequently, steam contamination has been steadily reduced. Troublesome turbine blade deposits may occur with surprisingly low (0.6 ppm) total solids contamination in steam. In the 3.5–6 MPa range, however these deposits are usually water soluble and can be removed by periodic washing. In the 4 to 10 MPa range, however, silica deposits predominate and these deposits are not easily removed by water washing. With operating pressure of 13 MPa and above insoluble deposits do occur which may be controlled by residual water washing. Before the unit is returned to service, the deposits should be removed by air or water‐driven turbine cleaners or by chemical cleaning.

The present study is undertaken in the region of Guelma that is located in North-Eastern Algeria. Guelma’s agricultural plain is irrigated from the Seybouse ephemeral river (wadi). The latter collects the entire domestic and industrial wastewaters of the region that are discharged without prior treatment. Hence, the organic and biological or what so ever contributions to the wadi are capable of initiating a significant degradation of its waters’ quality and challenging their use for irrigation. The paper aims to discuss these issues.

The interpretation of the results of three sampling campaigns for chemical and bacteriological analyzes was carried out in terms of the indices’ method (organic pollution index (OPI) and microbiological quality index (MQI)). The results were statistically assessed through the use of the principal component analysis (PCA). The OPI was calculated according to the method of Leclercq and Maquet (1987) whose principle is to classify the contents for the polluting elements into 5 classes each class corresponding to a given range for the considered parameter, and then to calculate the overall average class number for each sample. The MQI depends on the water concentrations in: the total coliforms, the fecal coliforms, and fecal streptococci. One defines five classes of concentrations for each of these parameters. The MQI is again the overall mean of the numbers for the classes for every parameter.

The OPI reflects a moderate pollution for most sampling stations. The PCA indicates that the variables controlling salinity are mainly Cl⁻, Na⁺ and SO₄²⁻. In August 2016, El-Fedjoudj pumping station shows a very strong fecal contamination. According to the recommendations of World Health Organization (1989), waters from wadi Seybouse cannot be used for the irrigation of vegetable crops if they were to be consumed raw.

This study has an environment impact as it reveals the need to protect surface waters used for irrigation and therefore protect consumers of raw vegetables that are to be consumed uncooked.

This paper aims to define the current and potential extent of seawater intrusion in Manukan Island under different scenarios of varying recharge and pumping rates. The calibrated model was also used to predict the extent of seawater intrusion in low lying area of Manukan Island for two years with all conditions assumed to remain the same as those in December 2009.

Different scenarios of varying recharge and pumping rates based on threats received by Manukan Island were investigated. El‐Nino events and overpumping are represented by varying recharge and pumping rates. Simulation was done using SEAWAT‐2000, the latest modeling software available in groundwater modeling that couples flow and transport together.

The seawater‐freshwater mixing ratio moves landwards after two years of simulation in Scenario 1. In order to control overpumping in this study area, Scenario 2 has resulted in backward movement of the 1.4 percent seawater‐freshwater mixing ratio toward the coast after two years of prediction. The current contamination of the coastal aquifers by seawater intrusion will be more severe with an impact of El‐Nino events on groundwater resources depletion in Scenario 3. Reductions of pumping and recharge rates in Scenario 4 have worsened the seawater intrusion problem. With the aid of artificial recharge in Scenario 5, highest hydraulic heads and lowest chloride concentration were observed.

The sustainable groundwater management selected for Manukan Island's current situation will be Scenario 2. In view of the effects of El‐Nino events in the future, Scenario 5 can be implemented to restore groundwater resources. The numerical model has showed the groundwater condition during El‐Nino events and overpumping illustrated that simulation modeling is an excellent tool to understand the behavior and management of an aquifer system. The output of simulation modeling via numerical model provides a framework toward groundwater management. Thus, current study output with similar approach which will restore groundwater (artificial recharge and reduction of pumping rate) can be applied in other small islands of similar hydrogeological condition and stresses for the purpose of groundwater resource protection.

Briefly, these findings will effectively contribute to water policy analysis, planning and management in the study area to combat current as well as future seawater intrusion problem.

The purpose of this study was to define and outline areas prone to disease causing elements by analyzing the spatial distribution and concentration of toxic and essential elements in a section of the Voltaian sedimentary basin.

A total of 2,668 soil samples were analysed by the inductively coupled plasma mass spectrometry technique and were re-appraised by comparing with baseline values of elements accepted globally to be in soils. The concentrations of arsenic (As), chromium (Cr), iron (Fe) and magnesium (Mg) were evaluated. Factor analysis, hierarchical cluster analysis and principal component analysis multivariate techniques were used to identify the source patterns of the elements in the soils. The Getis-Ord Gi method was used to generate the optimised maps for these selected elements. These maps spatially defined and outlined high value clusters which imply potential pollution or areas with high background values (hotspots), whereas the low value clusters imply areas with low background values (cold-spots).

The multivariate analysis supports a dominant geogenic source of these heavy elements with obvious influences from variably metamorphosed mafic–ultramafic rocks known to have contributed to the deposition of sediments in the basin. The hotspots for As were located around Nalerigu and to the east of Nawchugu. A Cr hotspot was located to the east of Nawchugu with Cr cold-spots located within Nalerigu and Yunyuo. Fe hotspots were observed to the south of Nalerigu and the east of Nawchugu with Fe cold-spots around Yunyuo, Bongo-Da and Nagbo. The spatial maps demonstrated the presence of toxic and deficient areas of all the selected elements used in the investigation. Therefore, it suggested the likely health implications depending on the exposed elements, their pathways and recommended the usefulness of using the results displayed in the spatial maps to guide in devising appropriate remediation techniques.

This paper fulfils an identified need to study the distribution of elements and the possible effects it may have on the health and livelihoods of those residing in these areas.