Waarom ligt de aarde niet bezaaid met lege schelpen van landslakken?

Apparently the fate of the shells of terrestrial gastropods after the death of the animal is poorly studied. The author started an experiment by following weight-loss of empty Helix aspersa shells in the field. The first results indicate 4% loss in weight of these empty shells in 3 months due to dissolution. Other possible mechanisms for removal of empty shells are: transport by water; consumption of empty shells by birds, in particular during the bird’s egglaying period; and other gastropods scraping lime from empty shells to use for the construction of their own shells.