Global rarity of intact coastal regions

Abstract

Management of the land–sea interface is essential for global conservation and sustainability objectives because coastal regions maintain natural processes that support biodiversity and the livelihood of billions of people. However, assessments of coastal regions have focused strictly on either the terrestrial or marine realm. Consequently, understanding of the overall state of Earth's coastal regions is poor. We integrated the terrestrial human footprint and marine cumulative human impact maps in a global assessment of the anthropogenic pressures affecting coastal regions. Of coastal regions globally, 15.5% had low anthropogenic pressure, mostly in Canada, Russia, and Greenland. Conversely, 47.9% of coastal regions were heavily affected by humanity, and in most countries (84.1%) >50% of their coastal regions were degraded. Nearly half (43.3%) of protected areas across coastal regions were exposed to high human pressures. To meet global sustainability objectives, all nations must undertake greater actions to preserve and restore the coastal regions within their borders.

Vertical Saltwater Intrusion in Coastal Aquifers Driven by Episodic Flooding: A Review

“…Human activities have drastically altered the global coastline (He & Silliman, 2019; Williams et al., 2021), and investigations assessing how these alterations interact to lessen or exacerbate vertical SWI are critical as coastal populations continue to grow (Figure 6). Salinization of wells is often observed in the hours immediately following a seawater flooding event, although it typically takes much longer for seawater to percolate through the vadose zone (Bailey & Jenson, 2014; Cardenas et al., 2015).…”

Scale‐dependent effects of marine subsidies on the island biogeographic patterns of plants

“…However, determining the drivers of these variable effects is an important next step to improve our understanding of the meta‐ecosystem that encompasses the land–sea interface (Loreau et al, 2003 ). Indeed, despite coastal regions (including islands) hosting both disproportionately high degrees of human impacts (Williams et al, 2021 ) and contributions to biodiversity (Ray, 1991 ), our understanding of cross‐boundary processes at various scales at the land–sea interface remains limited (Fang et al, 2018 ).…”

Greater Consideration of Animals Will Enhance Coastal Restoration Outcomes

“…2012 ), overconsumption of planted seagrass by herbivores ( figure 2 , action 4B; Wendländer et al. 2019 ), overgrazing of macroalgae by urchins (Eger et al. 2022 ), and grazing and trampling of saltmarsh by ungulates (Davidson et al.…”