Long time-series monitoring of an abyssal site in the NE Pacific: an introduction

Abstract

Deep-Sea Research II 45 (1998) 573—586 Long time-series monitoring of an abyssal site in the NE Pacific: an introduction K.L. Smith, Jr.!,*, E.R.M. Druffel ! Marine Biology Research Division 0202, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0202, USA Department of Earth System Science, University of California, Irvine, Irvine, CA 92697, USA Received 20 October 1997; in revised form 31 October 1997; accepted 4 November 1997 1. Introduction Abyssal regions of the world ocean cover more than 50% of the Earth’s surface (Gage and Tyler, 1991) but the biogeochemical processes in the sediments and deep water column of this vast expanse of our globe are poorly understood. The cycling of material through these deep-sea regions is intimately linked to the organic matter produced in the euphotic zone. The material sinks as particulate matter, undergoing various physical and biochemical transformations in the water column before reach- ing the seafloor. Temporal variability of plankton production in the upper ocean is well documented. The fraction of this production that escapes the euphotic zone as particulate organic matter sinking into the deep sea also exhibits temporal variability, reflecting the changes in surface water production. Independent long time-series measurements of particulate organic matter fluxes to abyssal depths (e.g. Deuser et al., 1981; Honjo, 1982; Deuser, 1986; Haake et al., 1993) and time-lapse photographic records of phytodetrital pulses reaching the sea floor (e.g. Billett et al., 1983; Lampitt, 1985; Rice et al., 1986), although taken in widely separated areas of the deep ocean, have been invaluable for predicting events in other regions. However, the cycling of organic matter in the deep ocean has been difficult to evaluate because synoptic measurements on sufficiently long time scales are rare. The lack of long time-series measurements to examine concurrently the input of a pelagi- cally derived food supply and its impact on benthic boundary layer (BBL) processes *Corresponding author. Fax: 001 619 534 7313; e-mail: ksmith@ucsd.edu. 0967-0645/98/$19.00 ( 1998 Elsevier Science Ltd. All rights reserved. PII: S 0 9 6 7 - 0 6 4 5 ( 9 7 ) 0 0 0 9 4 - 5