|| 要旨トップ | 目次 |||日本生態学会第62回全国大会 (2015年3月、鹿児島) 講演要旨
一般講演（口頭発表） G1-05 (Oral presentation)
Increase in air CO2 is causing concurrent increase in oceanic CO2 value, leading to a drop in seawater pH, known as Ocean Acidification (OA). OA specially affects calcareous species such as corals and mollusks. Many previous studies examined the OA impacts on tropical species such as corals, whereas its effects on cold-current species are not well understood yet. This study aims to examine the OA effects on calcareous sessile epifauna in a seagrass bed of Akkeshi-ko estuary, Hokkaido, where cold-current Oyashio affects its oceanography.
Three abundant calcareous sessile epifauna in Zostera marina bed, two spirorbid polychaete Neodexiospira brasiliensis and Circeis spirillum, and one bryozoan species were used. During five weeks of experiment, each species were kept under three different conditions, “Extreme”, “High” and “Control” with approximate pCO2 value of 3000, 1000 and 700 ppm respectively, then analyzed for a variation in survival, growth and recruitment rate for evaluation.
The responses to CO2 enrichment varied substantially among different species and among objective variables. Mostly they showed negative responses, but some even showed positive responses. The observed variation may be related to their differences in shell mineral composition, physiology and life traits.