Biomass and respiration of nematode populations in two moss communities at Signy Island, maritime Antarctic

1. The biomasses of free-living soil nematodes from a moss turf and a moss carpet, two contrasting bryophyte ecosystems in the maritime Antarctic, are analysed and compared with other tundra studies. 2. The mean annual live-weight biomass of nematodes from the moss turf ranged from 105 to 355 mg m-2, that from the moss carpet showed less variation being from 222 to 236 mg m-2. 3. Seasonal variations from a low winter biomass to a high summer value are explained by seasonal fluctuations in soil temperature. 4. Total annual nematode population respiration at the two sites was very similar, being 1726.1 μl O2 m-2 d-1 in the moss turf and 1761.0 μl O2 m-2 d-1 in the moss carpet. 5. Nematodes form an important part of the soil fauna and are responsible for 16% and 35% of the metazoan respiration in the moss turf and carpet respectively. 6. The short Antarctic summer and generally low temperatures limit nematode production to 0.95 and 1.12