39 Impacts on Coastal Communities

Loss of Biodiversity

Combined impacts from anthropogenic pressures and climate change threaten the capacity of coastal ecosystems to protect communities from hazards. Anthropogenic threats, including overexploitation, pollution, development, and habitat degradation, have triggered losses in habitat coverage across many coastal ecosystems, with global declines measuring 85% in oyster reefs (Beck et al., 2011), ~ 19–29% in seagrass meadows (Dunic et al., 2021; Waycott et al., 2009), ~ 50% in coral reefs (Eddy et al., 2021), 42% in salt marshes (Gedan & Silliman, 2009), 35% or higher in mangroves (Goldberg et al., 2020; Polidoro et al., 2010; Valiela et al., 2001), and also prevalent in kelp (Eger et al., 2022; Krumhansl et al., 2016). Losses in habitat cover directly remove the structural components of the ecosystem (e.g., vegetation, reef substrate) that are largely responsible for coastal protection. Experimental evidence suggests that removing marsh vegetation limits the ability of marshes to reduce wave energy (Möller et al., 2014), and modelling efforts demonstrate linkages between coral reef loss and increases in wave energy (Sheppard et al., 2005). As habitats are degraded or lost, their ability to provide ecosystem services, such as flood protection, is expected to decline (Estoque et al., 2018; Temmerman et al., 2012). Mangrove deforestation in Myanmar, for example, decreased the total value of mangrove-associated ecosystem services by almost 30% over 14 years, of which almost 11% was attributed to a loss of coastal protection services (Estoque et al., 2018).

This text is from “What evidence exists on the performance of nature-based solutions interventions for coastal protection in biogenic, shallow ecosystems? A systematic map protocol” by Avery B. Paxton, Trevor N. Riley, Camille L. Steenrod, Carter S. Smith, Y. Stacy Zhang, Rachel K. Gittman, Brian R. Silliman, Christine A. Buckel, T. Shay Viehman, Brandon J. Puckett and Jenny Davis, which is licensed under CC BY 4.0 

Sea Level Rise

Rising sea levels, primarily driven by climate change, pose a significant threat to coastal communities. Higher sea levels can lead to coastal erosion, increased flooding, and the intrusion of saltwater into freshwater aquifers, which can contaminate drinking water supplies.

Coastal Erosion

Natural processes, exacerbated by human activities such as urban development and mining of sand, can lead to the erosion of coastal land. This can result in the loss of property, infrastructure, and even entire communities.

Storm Surges and Cyclones

Coastal areas are more susceptible to the destructive forces of cyclones and tropical storms. Storm surges, in particular, can cause widespread flooding and damage to buildings and infrastructure.

Infrastructure Vulnerability

Coastal communities often have critical infrastructure located near the coast, such as ports, airports, and power plants. These assets are vulnerable to damage from storms and sea level rise, which can disrupt local economies and services.

Economic Impacts

Coastal communities often depend on tourism, fishing, and maritime industries. Any disruption caused by environmental factors or extreme weather events can have a severe economic impact, leading to job losses and decreased income.

Social Displacement

Rising sea levels and coastal erosion can force people to abandon their homes and communities, leading to social displacement and relocation challenges.

Health Risks

Coastal communities are at risk of health-related issues, including waterborne diseases, as contaminated seawater can affect drinking water sources and recreational areas.