Integrative Oceanography Division, Scripps Institution of Oceanography, University of California San Diego, San Diego, CA 92007, USA.
University of California, Santa Cruz, CA 95064, USA.
Proc Biol Sci. 2021 Aug 25;288(1957):20210950. doi: 10.1098/rspb.2021.0950. Epub 2021 Aug 18.
As biodiversity loss accelerates globally, understanding environmental influence over biodiversity-ecosystem functioning (BEF) relationships becomes crucial for ecosystem management. Theory suggests that resource supply affects the shape of BEF relationships, but this awaits detailed investigation in marine ecosystems. Here, we use deep-sea chemosynthetic methane seeps and surrounding sediments as natural laboratories in which to contrast relationships between BEF proxies along with a gradient of trophic resource availability (higher resource methane seep, to lower resource photosynthetically fuelled deep-sea habitats). We determined sediment fauna taxonomic and functional trait biodiversity, and quantified bioturbation potential (BPc), calcification degree, standing stock and density as ecosystem functioning proxies. Relationships were strongly unimodal in chemosynthetic seep habitats, but were undetectable in transitional 'chemotone' habitats and photosynthetically dependent deep-sea habitats. In seep habitats, ecosystem functioning proxies peaked below maximum biodiversity, perhaps suggesting that a small number of specialized species are important in shaping this relationship. This suggests that absolute biodiversity is not a good metric of ecosystem 'value' at methane seeps, and that these deep-sea environments may require special management to maintain ecosystem functioning under human disturbance. We promote further investigation of BEF relationships in non-traditional resource environments and emphasize that deep-sea conservation should consider 'functioning hotspots' alongside biodiversity hotspots.
随着全球生物多样性的加速丧失，了解环境对生物多样性-生态系统功能（BEF）关系的影响对于生态系统管理变得至关重要。理论表明，资源供应会影响 BEF 关系的形态，但这需要在海洋生态系统中进行详细的调查。在这里，我们利用深海化学甲烷渗漏和周围沉积物作为天然实验室，对比 BEF 代理之间的关系，以及营养资源可用性的梯度（较高的资源甲烷渗漏，到较低的资源光合作用驱动的深海栖息地）。我们确定了沉积物动物区系分类和功能特征生物多样性，并量化了生物扰动潜力（BPc）、钙化程度、现存量和密度作为生态系统功能代理。在化学合成渗漏栖息地中，关系呈强烈的单峰型，但在过渡性的“化学波动带”栖息地和依赖光合作用的深海栖息地中则无法检测到。在渗漏栖息地中，生态系统功能代理在最大生物多样性以下达到峰值，这表明少数专门物种在塑造这种关系方面可能很重要。这表明，在甲烷渗漏处，绝对生物多样性不是衡量生态系统“价值”的良好指标，这些深海环境可能需要特殊的管理，以在人为干扰下维持生态系统的功能。我们提倡在非传统资源环境中进一步调查 BEF 关系，并强调深海保护应考虑“功能热点”以及生物多样性热点。
