摘要：Three arrays, each containing four funnel-shaped sediment traps, were deployed near the front of the Müller Ice Shelf, Lallemand Fjord, western Antarctic Peninsula, in late austral summer 1998. Although the upper traps in each array were damaged or lost, eight others were recovered intact about 13 mo later. The mean flux of sediment was 1.4 to 2.9 mm a −1 (1.67 to 3.5 kg m −2 a −1 ) and showed little trend with respect to distance from the ice shelf or depth of water. Mean organic carbon and biogenic silica concentrations are 0.6 to 1.1% and 3.4 to 5.0%, respectively. Up to 50 microlaminae visible in x-radiographs probably indicate storm surges or the effect of spring tidal cycles. The sand content in most traps is 2 to 5 times lower in winter, reflecting reduced melt from icebergs and their limited mobility as they are held by sea ice. However, a secondary winter peak in very coarse sand is probably associated with eolian input during winter storms. Nitrogen is greater by 2 to 3 times in summer sediment, and organic carbon is up to 4 times greater. Biogenic silica shows less summer to winter difference, although the spring diatom bloom is represented by somewhat greater values in most traps. Summer values of isotopic organic carbon δ 13 C and total nitrogen δ 15 N are lower than winter values in response to heterotrophic removal of the lighter isotopes.
