From review to redesign: methodological advances in marine key-habitat mapping and management in the Central-Eastern Atlantic Archipelagos

Abstract

The conservation of ocean ecosystems is a global priority due to their essential role as life- support systems for the Biosphere, their ecological significance, and their socio-economic value. Strategic habitats such as seagrass meadows, rhodolith beds, and coral reefs, including Cold-Water Corals (CWC) are keystone elements. These habitats, formed by ecosystem-engineering organisms, create complex structures that enhance biodiversity through habitat cascades and facilitate the settlement of numerous species. Seagrass meadows function as nursery and refuge areas for numerous species, including those of fishery interest. Seagrass meadows function as nursery and refuge areas for numerous species, including those of fishery interest, act as natural filters that improve water quality, stabilize sediments, and serve as efficient carbon sinks. Rhodolith beds convert soft sediments into hard substrates, provide essential nurseries for benthic fauna, and contribute significantly to long-term carbon sequestration. Coral reefs, particularly CWCs, occupy only a small fraction of the seafloor yet represent biodiversity hotspots. In overall, these keystone habitats play a fundamental role in coastal protection, fisheries maintenance, and ecotourism promotion. These habitats are under threat from anthropogenic pressures such as bottom trawling, pollution, eutrophication, and climate change. This vulnerability is particularly acute in island regions such as the archipelagos of Azores, Madeira, Canary Islands and Cabo Verde in the Central East Atlantic and the archipelago of São Tomé and Príncipe in the Gulf of Guinee, where geographic isolation and high dependence on coastal resources increase the risk of irreversible degradation[...]