. Bulletin. Science; Natural history; Natural history. 22 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 118°30' 118°20'. SEDIMENT, BENTHOS TR/WL DEPTH IfTMETERS 0 12 3 KILOMETERS Fig. 1. Sampling sites on the Palos Verdes shelf and slope. Five of 11 benthic/sediment transects are labelled (0, 1, 3, 6 and 10); stations are located at 30-, 61-, 152- and 305-m water depth. The 4 trawl transects (TO, Tl, T4 and T5) and 3 water depths sampled (23-, 61- and 137-m) are indicated. The outfall system extends offshore from Whites Point. In the early 1970s, prior to improved source control and treatment practi
. Bulletin. Science; Natural history; Natural history. 22 SOUTHERN CALIFORNIA ACADEMY OF SCIENCES 118°30' 118°20'. SEDIMENT, BENTHOS TR/WL DEPTH IfTMETERS 0 12 3 KILOMETERS Fig. 1. Sampling sites on the Palos Verdes shelf and slope. Five of 11 benthic/sediment transects are labelled (0, 1, 3, 6 and 10); stations are located at 30-, 61-, 152- and 305-m water depth. The 4 trawl transects (TO, Tl, T4 and T5) and 3 water depths sampled (23-, 61- and 137-m) are indicated. The outfall system extends offshore from Whites Point. In the early 1970s, prior to improved source control and treatment practices, wastewater discharge significantly altered the Palos Verdes shelf environment. Sulfide-rich blackened sediments were reported, with elevated metals, DDT and PCBs in surface sediments and to 20 cm depth near the discharge (Galloway 1972; Southern California Coastal Water Research Project 1973). Concentrations de- creased with distance from the outfall system. Shelf benthic infaunal assemblages were dominated by polychaetes, with many Schistomeringos longicornis (syn- onyms Dorvillea articulata and Stauronereis rudolphi) and Capitella spp near the outfall, and Chaetopterus variopedatus beds in the nearshore by Long Point (Allan Hancock Foundation 1965; Jones 1969). Crustaceans and echinoderms were rare, and many infaunal species were conspicuously absent near the outfalls. The giant kelp {Macrocystis pyrifera) canopy had virtually disappeared from the Palos Verdes rocky subtidal by 1958, partly as a result of discharged effluent particulates (California State Water Quality Control Board 1964). These reduced light transmissibility in the water column, introduced a floe and toxicants, and buried the substrate. Aided by transplanting efforts initiated in 1967 by the Cal-. Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the or
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Keywords: ., bookcentury1900, booksubjectnaturalhistory, booksubjectscience
