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The purpose of this paper is to review cases of artificial reefs built through additive manufacturing (AM) technologies and analyse their ecological goals, fabrication process, materials, structural design features and implementation location to determine predominant parameters, environmental impacts, advantages, and limitations.

The review analysed 16 cases of artificial reefs from both temperate and tropical regions. These were categorised based on the AM process used, the mortar material used (crucial for biological applications), the structural design features and the location of implementation. These parameters are assessed to determine how effectively the designs meet the stipulated ecological goals, how AM technologies demonstrate their potential in comparison to conventional methods and the preference locations of these implementations.

The overview revealed that the dominant artificial reef implementation occurs in the Mediterranean and Atlantic Seas, both accounting for 24%. The remaining cases were in the Australian Sea (20%), the South Asia Sea (12%), the Persian Gulf and the Pacific Ocean, both with 8%, and the Indian Sea with 4% of all the cases studied. It was concluded that fused filament fabrication, binder jetting and material extrusion represent the main AM processes used to build artificial reefs. Cementitious materials, ceramics, polymers and geopolymer formulations were used, incorporating aggregates from mineral residues, biological wastes and pozzolan materials, to reduce environmental impacts, promote the circular economy and be more beneficial for marine ecosystems. The evaluation ranking assessed how well their design and materials align with their ecological goals, demonstrating that five cases were ranked with high effectiveness, ten projects with moderate effectiveness and one case with low effectiveness.

AM represents an innovative method for marine restoration and management. It offers a rapid prototyping technique for design validation and enables the creation of highly complex shapes for habitat diversification while incorporating a diverse range of materials to benefit environmental and marine species’ habitats.

This chapter examines the Netherlands’ challenges in safeguarding its low-lying coastline against rising sea levels and the consequences of coastal defense strategies on marine life, particularly in relation to SDG14. Sea-level rise necessitates increased soft coastal defense strategies, affecting seafloor areas and marine biodiversity through sand extraction and sand nourishments. The use of hard structures for coastal defense contributes to the loss of natural coastal habitats, raising biodiversity concerns. The chapter explores the potential benefits of artificial hard surfaces as marine habitats, emphasising the need for careful design to prevent ecological problems caused by invasive species. Strategies for enhancing biodiversity on human-made hard substrate structures, including material variations, hole drilling, and adaptations, are discussed. The ecological impact of marine sand extraction is examined, detailing its effects on benthic fauna, sediment characteristics, primary production, and fish and shrimp populations. Solutions proposed include improved design for mining areas, ecosystem-based rules for extraction sites, and ecologically enriched extraction areas. The ecosystem effects of marine sand nourishments are also analysed, considering the impact on habitat suitability for various species. The chemical effects of anaerobic sediment and recovery challenges are addressed. Mitigation measures, such as strategic nourishment location and timing, adherence to local morphology, and technical solutions, are suggested. The chapter underscores the importance of education in Nature-based Solutions and announces the launch of a new BSc programme in Marine Sciences at Wageningen University & Research, integrating social and ecological knowledge to address challenges in seas, oceans, and coastal regions and support SDG14 goals.

The objective of this research is to evaluate the influence of mineral additions on the mechanical performances of polymer concrete. This study aims to propose a novel approach formulation of polymer concrete based on reduction in the quantity of the binder and disposal of large quantities of industrial by-products and household waste such as the marble, the brick and silica fume whose valuation in polymer concrete could be an interesting ecological and economical alternative. The incorporation of a rate of 10% brick powder affects the distribution of pores inside polymer concrete, that is, the pore diameters become thinner and decrease and the porosity becomes evenly distributed. The recycled mineral brick powder addition in polymer concrete mix improved the mechanical properties.

This polymer concrete was prepared by using polyester resin and two different types of sand, following a new formulation based on an empirical method. Furthermore, the optimal binder percentage was of 20% resin and a mixture of 52% dune sand and 48% quarry sand according to the Abrams method. To achieve our objective, five rates (from 2% to 10%) of brick powder, marble powder and silica fume were examined. Afterwards, its mechanical characteristics were evaluated via a three-point flexural with compressive resistance. The findings indicated that the addition of brick, marble and silica fume to polymer concrete increases the flexural strength with 21.84%, 12.76% and 9.07%, respectively.

Concerning the compressive strength, the best resistance is that of polymer concretes based on brick powder, and this economic formulation of polymer concrete serves the optimal cost/resistance ratio criteria. It allows an improvement in the mechanical resistance of concrete are obtained by adding brick powder that exceed that of the reference concrete.

In the past few decades, there has been several contribution concerning the subject of the reduction of the binder quantity in polymer concretes and adding the industrial and household wastes. However, previous studies revolving around the same area disregarded the effect of the brick powder, which appears scientifically of great importance for enriching the literature.

This study aims to evaluate the suitability of Ferrock as a green construction material by analysing its engineering properties, environmental impact, economic viability and adoption challenges. It also aims to bridge knowledge gaps and provide guidance for integrating Ferrock into mainstream construction to support the decarbonisation of the built environment.

It presents a systematic and holistic review of existing literature on Ferrock, comprehensively analysing its mechanical properties, environmental and socio-economic impact and adoption challenges. The approach includes evaluating both quantitative and qualitative data to assess Ferrock’s potential in the construction sector.

Key findings highlight Ferrock’s superior mechanical properties, such as higher compressive and tensile strength, and enhanced durability compared to traditional Portland cement. Ferrock offers significant environmental benefits by capturing more CO₂ during curing than it emits, contributing to carbon sequestration and reducing energy consumption due to the absence of high-temperature processing. However, the material faces economic and technical challenges, including higher initial costs, scalability issues, lack of industry standards and variability in production quality.

This review provides a comprehensive and up-to-date analysis of Ferrock. Despite being discussed for a decade, Ferrock research has been overlooked, with existing studies often limited and published in poor-quality sources. By synthesising current research and identifying future study areas, the paper enhances understanding of Ferrock’s potential benefits and challenges. The originality lies in the holistic evaluation of Ferrock’s properties and its implications for the construction industry, offering insights that could drive collaborative research and policy support to facilitate its integration into mainstream use.

Over decades, tourism has been over-valorized as a mechanism that leaves developing economies from poverty and pauperism. In fact, development theory has enthusiastically emphasized the nature of tourism as a sustainable activity that boosts local economies. Quite aside from this, some critical voices not only have questioned to what extent tourism alleviates local poverty but also the connection between tourism and poverty. An emerging field within tourism studies has plausibly discussed the conditions laying for poverty to become a commodity or a tourist attraction. In this context, the classic paradigm of tourism development has been radically shifted. There is a type of emerging morbid consumption (morbid taste) that makes the Other's pain a question of attraction. This chapter not only ignites a hot debate revolving around the nature of poverty tourism but also its main contradictions. These contradictions can be very well begged in a question: if we start from the premise poverty seems to be the main commodity to exchange for local culture, how can the industry of tourism eradicate poverty?