Effects of Dredging and Disposal on Some Benthos at Monterey Bay, California.
Abstract
The specific objectives of this study were to document; (a) Natural temporal variations in benthic assemblages and changes related to substrate stability, (b) the initial effects of dredging and subsequent recolonization, (c) the effects of disposal of dredged material on the benthos and subsequent recovery of the fauna, and (d) the role of faunal distribution and reproductive abilities upon recovery or recolonization of disturbed areas. The natural benthic assemblages differed with changes in the amount of sediment movement or substrate stability. Many animals characterized the relatively stable submarine ridges but few inhabited the unstable terrace slopes of the submarine canyon in Monterey Bay, California (Monterey Canyon); even fewer animals were found in channeled areas. Dredging in the channel areas removed 60 percent of the original population of bottom animals. After 1.5 years, the number of individuals was low but the species diversity and evenness indexes were higher than before dredging. The ultimate recovery of a disturbed area depends upon the timing of the action in relation to the reproductive cycles and distributive abilities of the benthic organisms in the area. Underwater disposal of dredged material should be made in unstable bottom areas if possible.
Document Details
- Document Type
- Technical Report
- Publication Date
- Oct 01, 1976
- Accession Number
- ADA032684
Entities
People
- John S. Oliver
- Peter N. Slattery