安定硫黄同位体比を用いた底生食物網における化学合成一次生産の寄与の定量評価

抄録

Quantifying the contribution of primary production by sulfur-oxidizing bacteria (SOB) to benthic food webs is important for understanding energy and material flows in aquatic ecosystems, including chemosynthesis-based ecosystems. Sulfur stable isotope ratios (δ³⁴S) are a powerful tool for assessing sulfide utilization by SOB in sediments. In this review, I introduce the methodological approaches (δ³⁴S-based mixing model) used for estimating the contribution of SOB-derived organic matter to the nutrient resources of benthic fauna, and highlight three case studies that used this method in a deep-sea chemosynthesis-based ecosystem, whale-fall ecosystems, and a freshwater lake ecosystem. Finally, I discuss the advantages and limitations of this method for improving evaluations.