EFFICIENCY OF ARTHROPOD EXTRACTION FROM SOIL CORES

Soil cores (5 x 15 cm) were heat-extracted in Tullgren-type funnels, t hen floated three consecutive times in a saturated sugar solution. The organic supernatant was decanted and searched for Conembola and Acari . Heat-extraction efficiency varied greatly between arthropod taxa, ye ars, dates within years, and single samples within sampling dates. Usi ng Onychiuridae as an example, effects of sugar flotation on the accur acy of population density estimates were discussed.