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Pipelines are seriously corroded due to the close distance between pipelines and high voltage transmission lines. The purpose of this paper is to study the influence of alternating current (AC) on corrosion behavior of X80 pipeline steel in coastal soil solution.

The corrosion behavior of X80 steel under different AC densities in coastal soil solution was investigated by electrochemical measurements and image processing technology. Furthermore, a quantitative description model of AC corrosion through fractal dimension of corrosion image was established.

The results show that under low AC density the X80 steel is mainly uniform corrosion, and once AC density reaches 150 A/m², the corrosion morphology gradually turns to pitting corrosion with irregular circle. For another aspect, the fractal dimension of corrosion images shows that the two/three-dimensional fractal dimension increase with the increase of AC density, presenting a linear and an exponential relationship respectively. In addition, the variation of the three-dimensional fractal dimension is the same as that of average corrosion rate. The threshold of the increasing trend of fractal dimension as well as corrosion type is 150 A/m².

The investigation provides a quantitative method to describe AC corrosion morphology through fractal dimension. Furthermore, the method is of benefit to process corrosion images automatically.

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.

To study the corrosion behavior of pipeline steel in coastal areas, a tidal seawater macro-cell corrosion device was built using a cycle soaking tank and a macro-cell corrosion facility to simulate the corrosion behavior of pipeline steel in a simulated coastal environment (dry and wet alternations during seawater-soil corrosion macro-cell processes).

The corrosion behaviors were studied via the weight loss method, electrochemical methods and morphological observations on corrosion.

The results show that during the initial stage of tidal seawater/soil macro-cell corrosion process of the X65 steel, the working electrode on the seawater side is the anode of the macro-battery. As corrosion progresses, the anode and the cathode of the macro-battery become inverted. As the area ratio and the dry – wet ratio increase, the time of anode and cathode inversion shortens. Galvanic current density decreases as the dry – wet ratio increases and increases as the area ratio increases. The corrosion process of macro-cell is affected by the reversal of anode and cathode. After the reversal of anode and cathode, the corrosion rate is mainly controlled by dry – wet alternating corrosion.

The corrosion behavior of a pipeline steel in a coastal environment was studied using a tidal seawater macro-cell corrosion device. The synergism effect between the tidal seawater and seawater-soil macro-cell on corrosion behavior was clarified.

Seawater intrusion represents a major problem in many coastal aquifers all over the world. It degrades the water‐quality and hence the groundwater may become unsuitable for domestic and agriculture purposes. Due to the direct hydraulic contact between the freshwater and saline water in coastal aquifers and the density difference between the two water bodies, the seawater migrates inland. The problem is exacerbated when the groundwater abstraction rates exceed the natural recharge from rainfall events. The key to controlling this problem is to maintain the proper balance between water being pumped from the aquifer and the amount of water recharging it. The purpose of this paper is to present a coupled transient finite element model for simulation of fluid flow and solute transport in soils with application to study seawater intrusion in coastal aquifers.

The model includes coupling of fluid flow and solute transport. Transient density‐dependent flow and the dependency of dispersion on velocity are considered. After validation, the model is applied to predict the seawater intrusion in the Wadi Ham aquifer, UAE in vertical sections and the results are compared with those from a commercial code (SEWAT) which was used to simulate seawater intrusion in the aquifer in a horizontal section.

A good agreement is observed between the results of the current model in the vertical cross‐section and those of SEWAT in the horizontal cross‐section for the case of Wadi Ham. The results show that the model can predict the extent of seawater intrusion (and the transition zone) and distribution of salt concentration in the aquifer with a good accuracy.

The developed model includes coupling of fluid flow and solute transport in saturated and unsaturated porous media. Transient density‐dependent flow and the dependency of dispersion on velocity are considered. The model has been applied to a real world case study. A combination of the results in vertical and horizontal sections has been used to build a 3D picture of seawater intrusion in the aquifer.

The development of models that allows the evaluation and prediction of erosion processes is an important tool for the management and planning of coastal systems. Mangrove forests systems are under threat by the impacts of erosion, which is also intensified by human activity (and aggravated in the scenarios of global warming and climate change). The purpose of this paper is to develop a model of geographic information systems (GIS) that can be used for any estuary area, but it can also be used for mangroves.

This paper uses georeferentiation which is defined as a set of parameters that best characterize the mangrove areas: elevation (m); geomorphology; geology; land cover; anthropogenic activities; distance to the coastline (m) and maximum tidal range (m). Three different methods are used to combine the various vulnerability parameters, namely, DRASTIC index, analytical hierarchy process (AHP) and square root of the geometric mean.

The three approaches presented in this work show different types evaluating vulnerability to erosion, highlighting a stronger overvaluation of the areas presented with a high vulnerability, through the use of DRASTIC index when compared with two other approaches. The use of the AHP shows similarity to the square root of the geometric mean model, but the AHP also presents a higher percentage of vulnerable areas classified as having medium to very high vulnerability. On the other hand, the use of square root of the geometric mean led to a higher percentage of areas classified as having low and very low vulnerability.

These three qualitative models, based on a cognitive approach, using the set of parameters defined in this research, are a good tool for the spatial distribution of erosion in different mangroves in the world.

Global warming and climate change scenarios require adaptation and mitigation options supported by science-based strategies and solutions.

In addition to climate changes, human activities in the sea coast area are also important in the context of coastal erosion. There is a need to consider possible measures of adaptation at a national level to solve this issue. The purpose of this paper is to analyze the findings of the interviews made by the author and come to conclusions about residents' attitude towards possible measures of adaptation to the coastal erosion in Latvia.

The research was made by interviewing those seashore residents whose households are most influenced by sea coast erosion along the entire coastline of Latvia in the areas where erosion rate is projected to be at least 6 m until the year of 2025.

Half of the interviewees consider hard coast defense structures as an effective adaptation measure to the sea coast erosion in households concerned. The other half would not support that because of either long‐term ineffectiveness or other unwilling consequences. Retreat as a strategy is acceptable only for quite a small part of interviewees.

The results of the research can be taken into consideration when making political decisions concerning adaptation to climate change.

This research aims to explore the role of awareness of harm and responsibility for environmental protection in reducing pollution from single-use plastic bags (SPBs) in coastal communities (CCs). To this end, this study develops and tests a unique model that explains residents’ intention to reduce the use of SPBs in coastal regions.

A questionnaire was used to collect data from 721 coastal residents in Vietnam. Structural equation modeling and moderation analysis were applied to test the proposed hypotheses.

The results show that awareness of the impact of SPBs on the environment and human health and awareness of the responsibility to protect the coastal environment significantly affect attitudes and intentions to reduce the use of SPBs. Moreover, such awareness of responsibility strengthens the attitude-intention relationship.

The findings suggest that CCs should not receive a lower priority in campaigns and efforts to reduce SPBs. In this regard, providing residents with free environmentally friendly bags and education programs on the impact of SPBs could be implemented.

CCs are directly impacted by pollution from SPBs. However, little is known about how this affects their polluting behavior. This study shows that CCs are not immune to polluting behaviors and that SPBs can be significant among residents. It also demonstrates that awareness of harm and feeling responsible for the environment are essential drivers of (intended) sustainable behaviors.

Coastal land reclamation (CLR) projects have become an effective solution for population growth while creating new market areas and expanding revenue streams. Although a few studies have been conducted on risk management in CLR projects, they had very little prioritisation on financial and economic risk management. Thus, this study aims to manage the financial and economic risks of CLR projects.

A quantitative research approach consisting of three Delphi rounds was adopted for this study. The findings of this study were analysed and validated using statistical tools.

This study identified 13 significant financial and economic risk factors in CLR projects, among which poor quality of the sand and soil, delays in making payments, unpredictability of the safety and security of the country and high dredging volumes were the most significant. Most of these risks have to be borne by the client and the contractor. Conducting environmental impact studies, following quality control procedures and increasing social awareness are significant strategies to handle the financial and economic risks of CLR projects.

This study addresses the literature gap pertaining to financial and economic risk management in CLR projects by identifying its overall process, including the identification of significant financial and economic risks based on the severity levels; risk allocation among the client, contractor and consultant; and suitable risk handling strategies for each significant financial and economic risk factor. Moreover, the findings of this study can be used to effectively deal with financial and economic risks in CLR projects while raising society’s awareness.

This paper aims to inform the readers an overview of expected impacts of sea level rise (SLR) and climate change on rice crops area, yield and the urgent need to build climate responsive infrastructures to a coastal district, Alappuzha – a high-risk area which is already under mean sea level (MSL). This research carried out to understand the realities and impacts with respect to the exposures of rise in SLR and possible inundation extent of crop land. The extreme precipitation events have caused crop loss and damage, numerous casualties and enormous economic loss in this district during the recent past and project the likely impacts under anticipated climate change.

Global sea levels have already been risen noticeably as a result of climate change, and this trend is anticipated to continue. To reflect on the research objectives, the paper projects a climate change scenario analysis and impact assessment on the major crop grown, i.e. rice, using a crop simulation model, DSSAT 4.7 as the first part of the study. QGIS 3.28 version and Erdas Imagine software were used for land use land cover analysis and to delineate possible inundation in the major land use land cover, especially in agriculture area under SLR scenario. It points out the need to equip the district urgently with climate responsive agriculture strategies as majority of the area comes under 10 mts of elevation as per the Sentinel 2 data. For better adapting to the current and future climate change impacts in the aspects of built environment such as early warnings in farm sector in particular and forests, urban water management, transportation systems, building construction and operation and land use planning in general. Climate change is no longer a policy issue alone; now it is a common man’s nightmare. For a coastal state like Kerala, extreme climate events during 2018 and 2019 and 2021 have posed substantial impacts and damages on the environment and society. The impacts hit the vulnerable communities in multiple ways.

From the analysis, it was revealed that there is an increasing trend in rainfall observed over the past three decades in Alappuzha district. It is projected that day and night time temperatures may increase in Alappuzha by 2.5°C and 2.6°C by 2100, respectively, under RCP 4.5. With unchecked pollution or emission reduction actions, warming may further rise and hence the median projection when SLR reaches 2.4 meters (8 ft) at Alappuzha to Cochin coast is 2130s. The possible inundation analysis shows that around 53.48% of the coastal agriculture land may be likely inundated if SLR is only with mitigation measures such as extreme carbon cuts, SLR rise can be delayed till 2200. Alappuzha is known as the rice bowl of Kerala; however, it is highly exposed to climate vulnerability in terms of its unique environmental geographical settings like coastal wetlands, lagoons and sand beaches. DSSAT simulations shows that Uma rice, a major ruling variety in the region, may have yield reductions of up to 13% in the near century for Alappuzha.

This paper in general explains the projected climate change perspectives for Alappuzha, a climate change hotspot of Kerala with respect to SLR and coastal agriculture. and a review of the progression of DRR in the built environment and mainstreaming CCA and DRR by government and other agencies in the state.

This study underscores the urgent need for climate-responsive agricultural strategies in Alappuzha, Kerala, due to anticipated sea level rise, climate change, and land use changes. Equipping farmers with the knowledge and tools to adapt is essential for ensuring food security and sustainable livelihoods. Implementing climate-resilient practices and technologies will help mitigate adverse effects on rice crops, promoting economic stability and resilience in the region. Involving local stakeholders in the adaptation process is crucial, as their participation can enhance collaboration, increase awareness, and accelerate the adoption of sustainable agricultural practices, making the transition smoother and more effective.

It is the responsibility of the scientific community to inform the knowledge gained for the benefit of the society, especially on criticality of altering the existing land use pattern and building climate resilient coastal infrastructures. Studies such as this can stand as basis for implementing planned adaption actions. This is to conclude that instead of working in silos, mainstreaming climate change adaptation holistically across sectors is very necessary at this crucial hour. Participatory action plans and policies involving all local stakeholders can strengthen awareness and fasten the learning processes for adaptation including managed retreats.

At present, there are no specific studies, on the impacts of climate change and SLR on rice cropping systems in the district which specifically inform how to mainstream adaptation in the agriculture strategies in low lying coastal zones of Alappuzha.

Mangrove has the potential to adapt climate change threats like sea level rise, extreme high water events, and coastal erosions. The large stretched root systems of the mangrove acts as a natural barrier to catch hold of the run off soil, leading to accretion of coastal areas. Due to human and other natural activities, mangroves in different parts of the world are being degraded. Citing examples from India, this chapter provides ways of unique mangrove comanagement system with the involvement of local communities, NGOs, and local governments.