Sandy shores
Detailed accounts of the ecology of sandy and muddy shores and their inhabitants can be found in Bassindale and Clark (1960), Brafield (1978), Brown and McLachlan (1990), Eltringham (1971), Evans and Hardy (1970), Hails and Carr (1975), Hayward (1994), Ranwell (1972) and Swedmark (1964).
The sizes of particles to which the name 'sand' is applied has been given as: coarse sand 2.0-0.5 mm; medium sand 0.5-0.25 mm; fine sand 0.25-0.062 mm (see Section 6.1.1).
Seashore sands contain particles of many types and sizes, often including silt and clay, deposited from many sources (see Section 8.2.1). The main constituent of sand on British coasts is silica fragments. Our yellow beaches often consist almost entirely of coarse siliceous sand. Grey, muddy beaches contain silica particles mixed with silt, clay and organic debris. Various other substances also contribute to sandy deposits; for example, fragments of shell, diatoms, calcareous algae, foraminifera, and, in low latitudes, coral. The beautiful white sand beaches on the west coasts of the Outer Hebrides in Scotland are formed mostly from shells and calcareous algae, and give rise to extensive lime-rich coastal grasslands, the machair.
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