. Bulletin. Science; Natural history; Natural history. ORGANISMS NEAR OUTFALLS, SANTA MONICA BAY, CA 59 CD .75 o .50 o CO .25 cz o U 1 - CO c â o ^_ o 1 CO ^ W83 S83 W84 S84 W85 S85 W86 S86 W87 S87 W88 S88 W89 S89 W90 S90 W91 S91 W92 Survey Fig. 6. Axis 1 ordination scores for 5-Mile outfall station Z2 and reference station CI located in 60 m of water on the Malibu shelf Scores from Station Z2 were significantly correlated with mass emissions (p = ) but the low R^ () indicated that the relationship was weak. This result indicated that
. Bulletin. Science; Natural history; Natural history. ORGANISMS NEAR OUTFALLS, SANTA MONICA BAY, CA 59 CD .75 o .50 o CO .25 cz o U 1 - CO c â o ^_ o 1 CO ^ W83 S83 W84 S84 W85 S85 W86 S86 W87 S87 W88 S88 W89 S89 W90 S90 W91 S91 W92 Survey Fig. 6. Axis 1 ordination scores for 5-Mile outfall station Z2 and reference station CI located in 60 m of water on the Malibu shelf Scores from Station Z2 were significantly correlated with mass emissions (p = ) but the low R^ () indicated that the relationship was weak. This result indicated that changes in the infaunal community lagged behind the trend of diminished solids as abundances of opportunistic species fell, and the outfall assemblage became more natural in species composition and abundance. Similar to the analysis performed above, ordination scores from the 5-Mile outfall (Station Z2) and the 60 m Malibu reference site (Station CI) were compared over time from 1983 through 1992 (Figure 6). The assemblage at Station Z2 reached the lowest point of the gradient in winter 1986, but then increased towards the reference site end of the gradient. Thompson (1992) performed a similar ordination analyses of infaunal data collected from the area of the 7-Mile sludge outfall to document the rate of recovery after termination of sludge disposal in 1987 (Figure 7). The trend of ordination scores over time indicated that the highly degraded assemblage present prior to termination displayed initial rapid recovery to more natural conditions, but the rate of recovery had slowed by 1990. Based on regression models, Thompson predicted that assemblages in the sludge field would reach reference site conditions by 2002. Species composition and abundance changed markedly around the outfalls as demonstrated by the ordination studies described above. As the outfall areas recovered, key indicator species of degraded, polluted, and transitional assem- blages reached maximum abundances,
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