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The southwest coastal region is part of an inactive delta of large Himalayan rivers and is protected from tidal surge by the Sundarbans mangrove forest. This area is the hub of all types of disasters such as cyclones, tidal surges, floods, drought, salinity intrusions, repeated waterlogging, and land subsidence. Cyclonic tidal surges and floods are the more common disasters, and their effects are frequently experienced at the local level. But silent and invisible disasters such as increased salinity, arsenic contamination, and drought affect local livelihoods, people, and environments in this region. The vulnerability of southwest region to increased salinity, arsenic contamination, and drought are the result of a complex interrelationship among biophysical, social, economical, and technological characteristics of the country. Moreover, in the current and foreseeable future, the country is likely to be affected by the biggest, most long-lasting, and global scale but silent disaster: increased salinity, natural arsenic contamination, and drought. Therefore, this region is thought to be the most disaster-prone region in Bangladesh because of natural disasters and highly vulnerable to the effects of climate change.

The Indus, Mekong, and Ganges River deltas, which have created one of the world’s largest delta and submarine fan system, currently contribute a major fraction of freshwater to East and South Asia. All these deltas are those regions in the world that face major challenges in their water sector due to population growth, urbanization, industrialization, sea-level rise, and salinity intrusion into inland and water bodies, all aggravated by climate change. Among them, salinity intrusion is currently one of the key issues that directly and indirectly cause water insecurity in East and South Asia, which ultimately hamper livelihood, agricultural production, and social interference. Hence, this chapter gives a comprehensive description on the nature and extent of the salinity problem, its adverse effects on livelihood and water sector, and then the focus goes to current and future sustainable water resource management within the delta to finally move on to conclusion and suggestions.

Mangroves constitute an important ecosystem because of their global extent and high productivity. These plants thrive in the intertidal zones of the tropics and subtropics that are characterized by regular tidal inundation and fluctuating salinity. Mangrove species are well adapted, both morphologically and physiologically, to survive under saline conditions, but in hypersaline environment their growth is reduced. The present chapter is a critical analysis on the impact of salinity on the growth of a common mangrove species (Hertiera fomes). The analysis has been carried out in the framework of Indian Sundarbans, which has contrasting salinity profiles in different segments owing to barrage discharge and siltation phenomena. Analysis of the decadal profile of salinity indicates a gradual lowering in the western Indian Sundarbans due to Farrakka barrage discharge and run-off from catchments. The central sector, however, exhibits a contrasting picture of increment of aquatic salinity through time, mainly due to disconnection of the Bidyadhari River with the Ganga–Bhagrirathi–Hooghly River system (in the western part). This has made the Matla River in the central Indian Sundarbans hypersaline in nature (that used to get water from the Bidyadhari River) finally leading to an insecure ecological condition for the growth and survival of mangroves. The possible remedial measures to combat the situation have also been listed considering the ecological framework of the study zone.

Salinity is one of the major problems in the coastal region of Bangladesh that contributes to 20% of the total land area. About 53% of the coastal region is affected by different degrees of salinity. Salinity intrusion in this area is mainly derived through climate change as well as anthropogenic factors that make this region more vulnerable. Hence, salinity intrusion has adverse effects on water, soils, agriculture, fisheries, ecosystem, and livelihoods of this region. To ensure the availability of food as well as drinking water, this chapter highlights how individual and community people have endeavored several adaptation measures to minimize salinity effects. Moreover, it further discloses governmental and other development organizations’ actions toward salinity to reduce its impacts.

The salinity of the oilfield produced water has a significant effect on steel corrosion. The purpose of this paper is to study the influence of salinity on corrosion behavior of X60 steel and it also provides basic for material selection of gas wells with high salinity.

The weight loss experiment was carried out on steel with high temperature and high pressure autoclave. The surface morphology and composition of corrosion scales were studied by means of scanning electron microscopy, energy dispersive spectroscopy and X-ray diffractometry.

The results show that as salinity increases, the corrosion rate of X60 steel will gradually experience a rapid decline stage and then a slow decline stage. X60 steel is mainly exhibiting uniform corrosion in the first rapid decline stage and pitting corrosion in the second slow decline stage. The increase in salinity reduces gas solubility, which, in turn, changes the morphology and density of the corrosion scales of X60 steel. At low salinity, loose iron oxides generated on the surface of the steel, which poorly protects the substrate. At high salinity, surface of the steel gradually forms protective films. Chloride ions in the saline solution mainly affect the structure of the corrosion scales and initiate pitting corrosion. The increased chloride ions lead to more pitting pits on the surface of steel. The recrystallization of FeCO₃ in pitting pits causes the corrosion scales to bulge.

The investigation determined the critical concentration of pitting corrosion and uniform corrosion of X60 steel, and the new corrosion mechanism model was presented.

The main aim of this study is to investigate the impact of climate change and water salinity on farmer’s income risk with future outlook mitigation. Salinity and climate change are a threat to agricultural productivity worldwide. However, the combined effects of climate change and salinity impacts on farmers' income are not well understood, particularly in developing countries.

The response-yield function and general maximum entropy methods were used to predict the impact of temperature, precipitation and salinity on crop yield. The target minimization of total absolute deviations (MOTAD)-positive mathematical programming model was used to simulate the impact of climate change and salinity on socioeconomic and environmental indicators. In the end, a multicriteria decision-making model was used, aiming at the selection of suitable climate scenarios.

The results revealed that precipitation shows a significantly decreasing trend, while temperature and groundwater salinity (EC) illustrate a significantly increasing trend. Climate change and EC negatively impact the farmer's income and water shadow prices. Maximum reduction in income and water shadow prices was observed for A2 scenario (−12.4% and 19.4%) during 2050. The environmental index was the most important, with priority of 43.4% compared to socioeconomic indicators. Subindex amount of water used was also significant in study area, with 28.1% priority. The technique for order preference by similarity to ideal solution ranking system found that B1 was the best climatic scenario for adopting climate change adaptation in the research region.

In this study, farmers' income threats were assessed with the aspects of different climate scenario (A1, A1B and B1) over the horizons of 2030, 2040 and 2050 and three different indicators (economic, social and environmental) in Northwestern region of Pakistan. Only in arid and semiarid regions has climate change raised temperature and reduced rainfall, which are preliminary symptoms of growing salinity.

The purpose of this paper is to investigate the mechanical properties changing of geopolymer cement under different brine salinity.

Geopolymer Cement of Class F Fly Ash and Class G Cement slurries were prepared according to API RP 10B. The optimum alkaline activator/cement and water/cement ratio of 0.44 was used for geopolymer and Class G cement samples, respectively. The alkaline activator was prepared by mixing the proportion of Sodium Hydroxide (NaOH) solutions of 8 M and Sodium Silicate (Na2SiO3) using ratio of 1:2.5 by weight. The slurries were cured for 24 hours at 130^oC and 3,000 psi in HPHT Curing Chamber followed by coring process. Both cement sample were immersed in brine water salinity up to 28 days with different brine salinity up to 30 per cent of NaCl. The mechanical properties were investigated using OYO Sonic Viewer-SX and Uniaxial Compressive Strength. The surfaces of the cement samples were extracted for Scanning Electron Microscope (SEM) and EDS tests to evaluate the morphology and chemical compositions of the cured samples.

The paper shows that geopolymer samples experiences strength reduction in brine water but the reduction rate of geopolymer is about half of the Ordinary Portland cement based oil well cement. The finding was also verified by SEM and EDS result.

This paper investigates the mechanical property changes of emerging geopolymer cement due to different water salinity. The results provide potential application of geopolymer cement for oil well cementing.

The paper aims to present a study on the effects of temperature and salinity on the vertical distribution of suspended sand concentration and transport rate on the basis of 1DV model.

The finite difference method based on the implicit scheme of Crank‐Nicolson with an irregular grid was used for the fluid flow equation and the implicit upwind scheme with a staggered grid for the equation of concentration diffusion. The model was applied to five tests of the data sets from the Delta Flume with three different cases of temperature and salinity on the basis of parameterisation of the kinematic viscosity, the turbulence‐related sediment mixing coefficient and the concentration at the reference level.

The computed results showed that the vertical distributions of suspended sand concentration depend on salinity and specially, on temperature. When temperature increases or salinity decreases, the settling process of particles occurs considerably faster. For fine sand, the discrepancy on suspended sand transport rates due to temperature or salinity decreases with wave height. For coarse sand, the effect of temperature and salinity is not much affected by the wave height.

The quantitative evaluation of the roles of salinity, especially temperature once again confirmed their importance for the sediment transport and the process of coastal morphology. The further sense from this research may suggest some new ideas on the tendency of evolution of sea bed due to the warming of the earth in the future.

Rice is the primary staple crop in South Asia and is cultivated mainly on lowland ecosystems usually fed by the monsoon. With increasing climatic volatility, exclusively rain-fed rice paddies have experienced a triple threat in droughts, floods and salinity. This study investigates the linkages of these abiotic stresses on yield and subsequent farmer decisions on varietal choice.

A path analytic model is conceptualized where the relationship between yield (conditional on abiotic stresses) and the varietal choice decision is mediated by adaptation motive (latent construct) and market exposure (observed construct). The path model is validated using 2,523 observations from Bangladesh farmers to obtain parameter estimates for direct effects and mediated effects indicated above.

Findings reveal that drought and flood impacts, in contrast to salinity impacts, are influential to both yield and varietal choice. The adaptation motive, however, is clear only in the case of salinity. Time preference of farmers and previous exposure to climate shocks predict adaptation motive substantively. The study reveals that market exposure is also a significant mediator of varietal choice in addition to the mediating effect of adaptation.

The study adopts a path analytic model which is able to capture direct, indirect and mediated effects between exogenous factors and varietal choice decision. While the models provide conclusive statistical evidence to the above hypotheses, within-area variations of behavior may not be captured adequately by the method.

Analyzing the complexity of varietal decision-making choice using a path analytical model is a novel contribution to the literature. The application itself is unique to the context applied. The findings complement the literature on varietal adoption in the context of climate resilient paddy systems.

The purpose of this paper is to assess the risk due to climate induced disasters in coastal regions. Coastal areas, being economically attractive and ecologically fragile, need altogether different development approaches. The paper also explores the applicability of stakeholder theory for managing coastal regions in a sustainable manner. This paper should help policymakers when making their decisions to maintain coastal regions’ prosperity.

The paper opted for an exploratory study using secondary information available at various levels. This paper presents the case study of the coastal region of Gujarat. It starts by evaluating the present status of the coastal resources and their degradation. It then assesses the risk due to climate induced coastal hazards. It has critically reviewed the policy response towards coastal issues and problems. The applicability of stakeholder approach had been tested for coastal management.

The paper has identified that in an absence of stakeholder approach, the current planning strategies have failed to deal with coastal issues and problems. The coastal region needs a special attention for sustaining its development. An integrated regional framework for coastal development is required which encompasses trade‐off among various sectors. The region needs a long‐term regional land use planning, which can facilitate the disaster resilience and adaptation strategies for local communities. Finally adopting a stakeholder approach is recommended, to improve the ecological productivity and biodiversity of the coastal region.

The research has important policy implications for the state of Gujarat and infers that the stakeholder approach is the most appropriate approach for planning the development of the coastal region.

The paper has direct policy implications for the government of Gujarat and Government of India. Coastal planning needs a systematic approach to have an integrated development. The use of stakeholder approach can solve many issues and problems of coastal conflicts. Such an approach is very important for the protection and sustainable development of the coastal region. This also has colossal relevance for any developing countries preparing coastal region development plans.

The suggestions incorporated in the paper have also looked into the consideration of environmental conservation and protection of rights to livelihood for marginalized groups such as fishing communities.

The use of stakeholder theory for public sector planning is a new approach in a research. The paper has delved into the requirement of stakeholder approach in coastal planning for developing the coastal economy and conserving the coastal environment.