Human and Climate-Induced Pressures on Coastal Dune Ecosystems: Effects on Biodiversity, Functionality and Ecosystem Services

Abstract

Coastal dune ecosystems are dynamic and unique ecosystems with a high ecological significance. These dynamic systems harbour a wide diversity of species and provide many ecosystems services such as coastal protection, the output of resources and recreation. However, the combined pressures of climate change and both direct and indirect human activities threaten these ecological important areas and the ecosystem services they provide. Therefore, this review examined how the direct and indirect human activities, alongside the effects of climate change, influence plant biodiversity, ecosystem functioning and resilience of provisioning, regulating and cultural ecosystem services in sandy coastal dune ecosystems.

An extensive literature research was performed to combine the results from a variety of articles with an interaction matrix to assess the impact of various stressors. The key findings suggest that coastal development and coastal engineering are the most severe impacts resulting from direct human activities, causing accelerated biodiversity loss, coastal erosion and coastal habitat loss. Indirect human activities, including deforestation, fragmentation, sediment input, organic pollution and eutrophication are significantly threatening the resilience of coastal ecosystems by further degrading the dune landscape. Additionally, pressures resulting from climate change including sea level rise, increased storm frequency, temperature rise and saltwater intrusion exacerbate these impacts, leading to synergistic effects that are reducing the ability of plants to adapt to the changing conditions and more intensified environmental pressures. As a result, the coastal dune ecosystems are reduced in total area and are moving more land inwards, causing a decline in ecosystem functionality and the associated provisioning, regulating and cultural ecosystem services.

This literature review highlights that most studies focus on short-term impacts of individual stressors, but do not study the combined and long-term effects of multiple stressors. The interaction matrix showed that multiple stressors interact with the same ecosystem components and ecosystem services, leading to synergistic effects that accelerate individual pressures. Additionally, pressures resulting from climate change can intensify the impacts of human activities and vice versa, creating reinforcing feedback loops. Further research should focus on investigating how climate change and human activities interact in the long-term to implement more effective and fitting conservation strategies for coastal dune ecosystems in the future.