Germination in Barrow, Alaska, Tundra Soil Cores

Abstract

Soil cores collected in Barrow, Alaska, in 1972 were frozen for 6 yr and then placed in a growth chamber or greenhouse. Chrysosplenium tetrandrum (Saxifragaceae) seedlings, 204.8 m-2 in the growth chamber and 39.2 m-2 in the greenhouse, were recorded. Distribution of seeds was patchy, with 25 of 37 surface (0-8 cm) cores yielding no seedlings. No seedlings appeared in subsurface (8-16 cm) cores. In addition to these seedlings, 6 spp. of mosses [Pohlia annotina, Leptobryum pyriforme, Bryum cryophila, Bartramia ithyphylla, Bryum spp.] fruiting bodies of 2 spp. of fungi [Scutellinia scutellata and a basidiomycete], and several algae [diatoms, blue-green and green] were observed. Germination of C. tetrandrum seeds collected from growth chamber plants showed that 33% germinated within 2 wk after harvest. Germination after cold treatment (-10.degree. C) was 55%, but, if cold treatment were preceded by a 3-day moist after-ripening period, germination was increased to 80%. Presence of fruit parts decreased germination (55-9% and 80-26% for non-after-ripened and after-ripened seeds, respectively). The data suggests the presence of allelochemics in the soil cores and in fruit parts surrounding the seeds. Soil cores could be used for other studies, including rates of recolonization, and such studies should utilize controlled environments.