Survival of frost and drought conditions in the soil by enchytraeids (Annelida; Oligochaeta) in Arctic, subalpine and temperate areas

Survival of enchytraeids from three areas was investigated: an oak forest (Quercus pubescens) in the vicinity of Vienna, Austria (420 m a.s.l., 48°16′N/16°21′E), a subalpine meadow in Lower Austria (1580 m a.s.l., 47°43′N/15°47′E) and an Arctic tundra heath at the Kongsfjorden, Spitsbergen (Ny-Ålesund: 78°30′N/11°5′E). In the two Austrian areas snow cover protected the enchytraeids during the 1998/99 winter from frost conditions in the soil. In laboratory experiments and in the field, worms developed from cocoons as well after drought as after subzero temperature exposure. The supercooling point (SCP) of individual worms was between –3.8 and –13.6 °C. A significant correlation existed between the quantity of gut content and survival at low temperatures. Most enchytraeid species, both in the field and in the laboratory, consumed more food at temperatures above 0 °C and most worms which survived frost, had no gut content.