Declining natural resources have contributed to a cultural renaissance across the Pacific that seeks to revive customary ridge‐to‐reef management approaches to protect freshwater and restore abundant coral reef fisheries. We applied a linked land–sea modeling framework based on remote sensing and empirical data, which couples groundwater nutrient export and coral reef models at fine spatial resolution. This spatially explicit (60 × 60 m) framework simultaneously tracks changes in multiple benthic and fish indicators as a function of community‐led marine closures, land‐use and climate change scenarios. We applied this framework in Hā‘ena and Ka‘ūpūlehu, located at opposite ends of the Hawaiian Archipelago to investigate the effects of coastal development and marine closures on coral reefs in the face of climate change. Our results indicated that projected coastal development and bleaching can result in a significant decrease in benthic habitat quality and community‐led marine closures can result in a significant increase in fish biomass. In general, Ka‘ūpūlehu is more vulnerable to land‐based nutrients and coral bleaching than Hā‘ena due to high coral cover and limited dilution and mixing from low rainfall and wave power, except for the shallow and wave‐sheltered back‐reef areas of Hā‘ena, which support high coral cover and act as nursery habitat for fishes. By coupling spatially explicit land–sea models with scenario planning, we identified priority areas on land where upgrading cesspools can reduce human impacts on coral reefs in the face of projected climate change impacts.
- Award ID(s):
- 1950656
- NSF-PAR ID:
- 10316982
- Date Published:
- Journal Name:
- Scientific reports
- Volume:
- 11
- ISSN:
- 2045-2322
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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Abstract The prevalence of coral bleaching due to thermal stress has been increasing on coral reefs worldwide. While many studies have documented how corals respond to warming, fewer have focused on benthic community responses over longer time periods or on the response of non-coral taxa (e.g., crustose coralline algae, macroalgae, or turf). Here, we quantify spatial and temporal changes in benthic community composition over a decade using image analysis of permanent photoquadrats on Palmyra Atoll in the central Pacific Ocean. Eighty permanent plots were photographed annually between 2009 and 2018 on both the wave-exposed fore reef (FR, 10 m depth,
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Abstract Satellite imagery is a useful tool for monitoring and mapping the distribution of invasive or nuisance algal species on coral reefs over the temporal and spatial scales needed for ecosystem management. Visual inspections of high-resolution satellite imagery were used to detect the newly discovered nuisance alga,
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