Science Inventory

The Power of Computer-aided Tomography to Investigate Marine Benthic Communities

Citation:

DAVEY, E. W., K. T. PEREZ, AND R. L. JOHNSON. The Power of Computer-aided Tomography to Investigate Marine Benthic Communities. Presented at 2008 Benthic Ecolohy Meeting, Providence, RI, April 09 - 13, 2008.

Impact/Purpose:

We think that CT technology can provide a unique view of the habitat utilization of MBC. This technology can be used to quantify marine macro faunal activity in sediments using two biologically related parameters: the percentage of tube and tunnel volume (PTTV) and the mean CT sediment attenuation of x-rays (SXA). Since CT scanners are available at most medical facilities, these CT techniques can be applied to environmental studies throughout many other areas of the world. Also, in the past 5 years, the medical CT scanners have become faster (~5 minutes to obtain 500 slices/30cm length core) with increased image resolution (slice thickness = 0.625 mm), and at costs (~$25.00/core) similar to those for common wet chemistry analyses. Therefore, we propose that the application of CT technology may be another effective tool to assess and monitor anthropogenic effects in aquatic and semi-aquatic (wetlands) sediment, and, perhaps, even more terrestrial environments.

Description:

Utilization of Computer-aided-Tomography (CT) technology is a powerful tool to investigate benthic communities in aquatic systems. In this presentation, we will attempt to summarize our 15 years of experience in developing specific CT methods and applications to marine benthic communities (MBC). In the past, we have utilized CT to correlate MBC to anthropogenic pollution gradients in Narragansett Bay and some stressed fjords in Sweden. In the laboratory, we have used CT with an added tracer to measure bioturbation in natural sediment cores and to observe and quantify the effects of different oxygen concentrations on the burrowing behavior of selected benthic biota. At the present time, we are attempting to define relationships between macro-benthic community composition and samples taken concurrently for: (1) CT based measurements of intact cores, (2) geophysical properties of sediments, and (3) acoustically delineated sediment habitats.

Record Details:

Record Type: DOCUMENT (PRESENTATION/ABSTRACT)
Product Published Date: 04/09/2008
Record Last Revised: 05/14/2008
OMB Category: Other
Record ID: 188823

Organization:

U.S. ENVIRONMENTAL PROTECTION AGENCY

OFFICE OF RESEARCH AND DEVELOPMENT

NATIONAL HEALTH AND ENVIRONMENTAL EFFECTS RESEARCH LABORATORY

ATLANTIC ECOLOGY DIVISION

WATERSHED DIAGNOSTICS BRANCH