Accession Number : ADA331560

Title :   Control of Benthic Processes by Oxygen and Topography.

Descriptive Note : Final rept.,

Corporate Author : SCRIPPS INSTITUTION OF OCEANOGRAPHY LA JOLLA CA MARINE LIFE RESEARCH GROUP

Personal Author(s) : Levin, Lisa A.

PDF Url : ADA331560

Report Date : 10 NOV 1997

Pagination or Media Count : 2

Abstract : Studies of bathyal settings in the Pacific and Indian Oceans indicate that macrobenthic communities are strongly influenced by abiotic factors including topography-induced flow, substrate mobility, bottom-water oxygen availability and organic-matter inputs. Mensurative and manipulative experiments conducted on Fieberling Guyot demonstrated that infaunal species composition, lifestyles, living positions, and colonization rates and mechanisms vary with sediment transport regime. Studies of the benthic fauna within oxygen minimum zones of the Oman margin (NW Arabian Sea) and on a seamount in the eastern Pacific suggest that oxygen and organic loading together affect macrobenthic species composition, diversity, and bioturbation potential. Strong zonation of mega- and macrobenthic communities was observed across the lower boundary of both oxygen minimum zones. Multiple regression of bathyal macrobenthic data from the Pacific and Indian Oceans indicate that together depth, latitude, sediment organic-carbon content and bottom-water oxygen concentration explain 52-87% of variation in measures of species diversity. Within oxygen minimum zones, bottom-water oxygen most affects species richness, while organic matter availability controls the distribution of individuals among species (evenness). Further understanding of marine benthic community structure will derive from investigation of interactions among abiotic factors, particularly those influenced by human activity. See attached listing of publications resulting from this grant.

Descriptors :   *SEDIMENT TRANSPORT, *AQUATIC ORGANISMS, *BOTTOM WATERS, SUBSTRATES, REGRESSION ANALYSIS, OXYGEN, PACIFIC OCEAN, COLONIES(BIOLOGY), INDIAN OCEAN, ECOLOGY, BENTHONIC ZONES, OMAN GULF, SEAMOUNTS, ARABIAN SEA.

Subject Categories : Biological Oceanography

Distribution Statement : APPROVED FOR PUBLIC RELEASE