SPATIAL AND TEMPORAL FACTORS AFFECTING SEDIMENT TURNOVER BY THE LUGWORM ARENICOLA-MARINA (L)

There were substantial differences in the amounts of sediment reworked by Arenicola mal ina (lugworms) on different parts of the shore and a t different times of the year. The amounts were affected by the densit y, distribution and movement of worms. Rates of cast production were a lso important, and they were affected by the nature of the substrate a nd temperature. The production of casts occurred at regular intervals during periods of high activity.