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Methane seeps are highly abundant marine habitats that contribute sources of chemosynthetic primary production to marine ecosystems. Seeps also factor into the global budget of methane, a potent greenhouse gas. Because of these factors, methane seeps influence not only local ocean ecology, but also biogeochemical cycles on a greater scale. Methane seeps host specialized microbial communities that vary significantly based on geography, seep gross morphology, biogeochemistry, and a diversity of other ecological factors including cross-domain species interactions. In this study, we collected sediment cores from six seep and non-seep locations from Grays and Quinault Canyons (46–47°N) off Washington State, USA, as well as one non-seep site off the coast of Oregon, USA (45°N) to quantify the scale of seep influence on biodiversity within marine habitats. These samples were profiled using 16S rRNA gene sequencing. Predicted gene functions were generated using the program PICRUSt2, and the community composition and predicted functions were compared among samples. The microbial communities at seeps varied by seep morphology and habitat, whereas the microbial communities at non-seep sites varied by water depth. Microbial community composition and predicted gene function clearly transitioned from on-seep to off-seep in samples collected from transects moving away from seeps, with a clear ecotone and high diversity where methane-fueled habitats transition into the non-seep deep sea. Our work demonstrates the microbial and metabolic sphere of influence that extends outwards from methane seep habitats.
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Understanding and valuing human connections to deep-sea methane seeps off Costa Rica
Methane seeps are highly productive ecosystems that provide carbon sequestration services, host diverse communities including endemic species, and serve as habitats for commercial fisheries. Little is known about the economic value the public places on them. Discrete Choice Experiments (DCEs) are administered to a sample of Costa Rican taxpayers to evaluate their willingness to pay (WTP) in monetary terms using tradeoffs made in a survey context involving three of the main attributes of methane seep ecosystems to provide insights for future conservation and management efforts. Extensive effort is devoted to understanding how Costa Ricans view different aspects of the deep sea. We find that they associate it with strange animals, natural resources, the unknown, and being far from reach. Perhaps surprisingly, they underestimate how much they know about the deep sea. We find that WTP for methane seep protection is the highest for programs that protect seeps with endemic species, followed by seeps with high climate change mitigation potential and commercial fishing habitat. Higher-income groups and women are more likely to prefer options that increase the current level of protection. We discuss how science communication and community engagement contribute to care expressed toward the deep sea.
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- Award ID(s):
- 2048720
- PAR ID:
- 10530168
- Publisher / Repository:
- Elsevier
- Date Published:
- Journal Name:
- Ecological Economics
- Volume:
- 223
- Issue:
- C
- ISSN:
- 0921-8009
- Page Range / eLocation ID:
- 108228
- Subject(s) / Keyword(s):
- Deep Sea, Methane Seeps Economic Valuation, Costa Rica
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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- Free Publicly Accessible Full Text
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Accepted Manuscript1.0
- Journal Article:
- https://doi.org/10.1016/j.ecolecon.2024.108228
