For each sample, five 5.7 cm diameter areas of mud were dark-adapted for 10 minutes. Then Fo as a measure of photosynthetic biomass was measured using a Heinz Walz Pulse Amplitude Modulation (PAM) fluorescence measuring device (Honeywill et al., 2002). Following this, frozen contact cores were taken from the same areas to a depth of ≈3 mm. Finally, the sediment in a 30× 30 cm quadrat around each core was collected for benthos to a depth of approximately 1 cm. This sampling method was used because, in MH1 and MH2, there is only a thin layer
of sediment over a thick mass of roots, which prevented sampling deeper sediment. It provides a similar amount of sediment to the more commonly used 10 cm diameter, 10 cm deep cores and gives a good representation of sparse and patchy fauna. MH3 was sampled to a similar depth to maintain consistency. Quadrats with a smaller area do not give good representations of many components of this sparse and patchy fauna.