scholarly journals Shelving the Coast With Vertipools: Retrofitting Artificial Rock Pools on Coastal Structures as Mitigation for Coastal Squeeze

2019 ◽  
Vol 6 ◽  
Author(s):  
Alice E. Hall ◽  
Roger J. H. Herbert ◽  
J. Robert Britton ◽  
Ian M. Boyd ◽  
Nigel C. George
2016 ◽  
Vol 67 (1) ◽  
pp. 123 ◽  
Author(s):  
Ally J. Evans ◽  
Louise B. Firth ◽  
Stephen J. Hawkins ◽  
Elisabeth S. Morris ◽  
Harry Goudge ◽  
...  

Coastal defences are proliferating in response to anticipated climate change and there is increasing need for ecologically sensitive design in their construction. Typically, these structures support lower biodiversity than natural rocky shores. Although several studies have tested habitat enhancement interventions that incorporate novel water-retaining features into coastal defences, there remains a need for additional long-term, fully replicated trials to identify alternative cost-effective designs. We created artificial rock pools of two depths (12cm, 5cm) by drill-coring into a shore-parallel intertidal granite breakwater, to investigate their potential as an intervention for delivering ecological enhancement. After 18 months the artificial rock pools supported greater species richness than adjacent granite rock surfaces on the breakwater, and similar species richness to natural rock pools on nearby rocky shores. Community composition was, however, different between artificial and natural pools. The depth of artificial rock pools did not affect richness or community structure. Although the novel habitats did not support the same communities as natural rock pools, they clearly provided important habitat for several species that were otherwise absent at mid-shore height on the breakwater. These findings reveal the potential of drill-cored rock pools as an affordable and easily replicated means of enhancing biodiversity on a variety of coastal defence structures, both at the design stage and retrospectively.


2020 ◽  
Vol 13 ◽  
pp. 194008292095191
Author(s):  
S. Y. Chee ◽  
J. L. S. Wee ◽  
C. Wong ◽  
J. C. Yee ◽  
Y. Yusup ◽  
...  

Coastlines are drastically altered globally due to urbanisation and climate-related issues. As a response, communities build coastal defence structures to protect people and property. Although these infrastructures fulfil engineering demands of coastal defences, the trade-off to nature includes a decrease in biodiversity able to live on these structures because of the lack of topographic complexity. Several studies have tried to increase the surface complexity on coastal defence structures through eco-engineering habitat enhancements that mimic nature. However, few of these studies have been conducted in tropical regions where effects are more pronounce due to desiccation and extreme heat. In this study, water-retaining structures (in the form of rock-pools at depths 12 cm, and 5 cm) were drill-cored into coastal defence structures (i.e. granite rock revetments) on reclaimed coastlines in Penang Island, Malaysia. We found greater species richness and an increase in community structure in the drill-cored rock pools regardless of the depth of these artificial rock-pools. Positive habitat selection also occurred within micro-habitats of this scale. The drill-cored artificial rock pools in these tidal exposed revetments also provided niche-spaces for marine organisms found in low-tide or sub-tidal areas. These findings demonstrate the potential of this eco-engineered habitat enhancement as a means of promoting biodiversity on granite rock revetments, which can be applied either during design phase of a coastal development or retrospectively.


Author(s):  
Valeria Chávez ◽  
Debora Lithgow ◽  
Miguel Losada ◽  
Rodolfo Silva-Casarin

AbstractInfrastructure is necessary to protect and provide the goods and services required by humans. As coastal green infrastructure (CGI) aims to respect and work with natural processes, it is a feasible response to mitigate or avoid the consequences of coastal squeeze. The concept of CGI is receiving increased attention of late due to the challenges facing us, such as climate change, population growth and the overexploitation of natural resources on the coast. Terms which may be applied to encourage the construction of infrastructure, or to minimize the responsibility for poorly made decisions, often induce misunderstanding. In this paper, the concept of CGI and its use in solving coastal problems is reordered. Four categories are proposed, according to the degree of naturalness of the project: Nature reclamation, Engineered ecosystems, Ecologically enhanced engineering, and De-engineering/Relocation. Existing coastal risk evaluation frameworks can be used to design many types of CGI. Key concepts, challenges and good practices for the holistic management of coastal squeeze are presented from the analysis of successful and unsuccessful CGI projects worldwide.


Author(s):  
Brent Wilson ◽  
Lee-Ann C. Hayek

Abstract The intertidal coastline of Ceredigion, Wales, comprises a patchwork of unstable sand and cobble beaches, and stable bedrock areas and boulder-fields. The last two shoreline types support rock-pools with growths of the red alga Corallina officinalis, the thalli of which are a popular substrate for calcareous epiphytes. Replicate samples of C. officinalis (four per site) were taken from (a) three bedrock sites (Ceinewydd, Aberystwyth Victoria Rocks and Castle Rocks) and (b) three boulder-fields (Llanon, Aberaeron lower shore (Aberaeron LS), Llanina) on the lower shore. The middle shore boulder field at Aberaeron (Aberaeron MS) was also sampled. These replicates were examined for calcareous meiofauna (63–2000 μm) not previously examined as a community: spirorbids, foraminifera, gastropods, bryozoans, ostracods and ophiuroids. These were assigned to sessile and vagile modes of life. The sessile association overwhelmingly dominated bedrock coastlines and the Aberaeron MS, while the vagile association was at its most abundant on the Corallina from lower shore, stable boulder-fields. Gastropods were almost entirely limited to Corallina on boulder-fields. We hypothesize that the boulders induce low-energy turbulence among breaking waves, allowing the less firmly attached vagile meiofauna to dominate on C. officinalis in rock-pools in lower shore boulder-fields. The small attachment area of sessile organisms allows them to settle bedrock sites in greater densities than do vagile organisms at boulder-field sites, which are presumed to require larger foraging areas.


Author(s):  
Steven Nolan ◽  
Marco Rossini ◽  
Chase Knight ◽  
Antonio Nanni

AbstractWithin the last century, coastal structures for infrastructure applications have traditionally been constructed with timber, structural steel, and/or steel-reinforced/prestressed concrete. Given asset owners’ desires for increased service-life; reduced maintenance, repair and rehabilitation; liability; resilience; and sustainability, it has become clear that traditional construction materials cannot reliably meet these challenges without periodic and costly intervention. Fiber-Reinforced Polymer (FRP) composites have been successfully utilized for durable bridge applications for several decades, demonstrating their ability to provide reduced maintenance costs, extend service life, and significantly increase design durability. This paper explores a representative sample of these applications, related specifically to internal reinforcement for concrete structures in both passive (RC) and pre-tensioned (PC) applications, and contrasts them with the time-dependent effect and cost of corrosion in transportation infrastructure. Recent development of authoritative design guidelines within the US and international engineering communities is summarized and a examples of RC/PC verses FRP-RC/PC presented to show the sustainable (economic and environmental) advantage of composite structures in the coastal environment.


Author(s):  
Andrew Cornett

Many deck-on-pile structures are located in shallow water depths at elevations low enough to be inundated by large waves during intense storms or tsunami. Many researchers have studied wave-in-deck loads over the past decade using a variety of theoretical, experimental, and numerical methods. Wave-in-deck loads on various pile supported coastal structures such as jetties, piers, wharves and bridges have been studied by Tirindelli et al. (2003), Cuomo et al. (2007, 2009), Murali et al. (2009), and Meng et al. (2010). All these authors analyzed data from scale model tests to investigate the pressures and loads on beam and deck elements subject to wave impact under various conditions. Wavein- deck loads on fixed offshore structures have been studied by Murray et al. (1997), Finnigan et al. (1997), Bea et al. (1999, 2001), Baarholm et al. (2004, 2009), and Raaij et al. (2007). These authors have studied both simplified and realistic deck structures using a mixture of theoretical analysis and model tests. Other researchers, including Kendon et al. (2010), Schellin et al. (2009), Lande et al. (2011) and Wemmenhove et al. (2011) have demonstrated that various CFD methods can be used to simulate the interaction of extreme waves with both simple and more realistic deck structures, and predict wave-in-deck pressures and loads.


Flora ◽  
2000 ◽  
Vol 195 (3) ◽  
pp. 257-266 ◽  
Author(s):  
Axel Krieger ◽  
Stefan Porembski ◽  
Wilhelm Barthlott

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