sediments, and ENSS was the dominant group. Assemblage B (ITSDs, ITMDi, ITMDs, INSS, INSDs, INMS, INMDi, INMO, INMC, ENMO) was found during 1957-60 and consisted of infaunal functional groups of mixed feeding types. This assemblage with a few added groups split into two distinct assemblages (C and D) during the remaining studies. Assemblage C was associated with muddy areas in Raritan and Sandy Hook Bays and assemblage D tended to be more abundant in Lower Bay.

temporal change

The benthic fauna in the Lower Bay Complex is characterized by moderate to large seasonal fluctu ations. Seasonal changes in abundance can be as much as several orders of magnitude in some locations (Fig. 18.4). The more variable station plotted in Figure 18.4 was located within a pit that had been created by sand mining, and it is likely that annual declines at this location were associated with low dissolved oxygen conditions created by poor flushing and high accumulation of organic matter at the bottom of the pit. The other station in this figure was located in a nearby, shallow sandy area that hadnever been disturbed by sand mining. Over the entire Lower Bay Complex, the benthic fauna in finer grained sediments tends to be more abundant and to fluctuate more on a seasonal basis than in sandy areas (Figs. 18.1a and 18.5).

Table 18.5. Mantel tests of biotic-environmental relationships. Faunal and environmental data from the regional studies cited in the text. Environmental data included grain-size (% gravel, sand, silt, clay, and median), depth, temperature and salinity when available

0 0

Post a comment