The interactive effects of (a) the length of exposure (time point (months)) × temperature regime on mean maximum bioturbation depth (cm, mean ± s.e.), (b) the length of exposure (time point (months)) × temperature regime and (c) [CO2] (ppm) × temperature regime on bioirrigation activity (Δ[Br−], mg l−1, mean ± s.e.) of A. virens. In a–c, temperature regimes are ambient (open circles) or ambient+4°C (filled circles).