. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 100 - Upper estuary so -< < 25 - Middle estuary so -{i Lower estuary 50 10 1 Species rank Figure 1. K-dominance curves for abundance (upcn circles) ami hin- mass (black ciirle.\l nl macrolauna in the upper, middle, and lower parts of the Qiiaslmel Riwr (/ell) and Childs River fright).. salinity range, eutrophication seemed to be responsible for dif- ferences in the composition and abundance of macrofauna be- tween estuaries. The abundance of oligochaetes and insect larvae and the occurrence of a large carnivore increas
. The Biological bulletin. Biology; Zoology; Biology; Marine Biology. 100 - Upper estuary so -< < 25 - Middle estuary so -{i Lower estuary 50 10 1 Species rank Figure 1. K-dominance curves for abundance (upcn circles) ami hin- mass (black ciirle.\l nl macrolauna in the upper, middle, and lower parts of the Qiiaslmel Riwr (/ell) and Childs River fright).. salinity range, eutrophication seemed to be responsible for dif- ferences in the composition and abundance of macrofauna be- tween estuaries. The abundance of oligochaetes and insect larvae and the occurrence of a large carnivore increased with nutrient loading, whereas the number and biomass of other typically res- ident species decreased. Most significantly, the ratio of poly- chaetes to oligochaetes was clearly lower in the Childs River () than in the Quashnet River (). We contrasted the benthic assemblages within the heavily nu- trient-loaded Childs River estuary to those of the more mod- erately loaded Quashnet River estuary by constructing plots of ranked species dominance (3). The biomass and abundance of each species were ranked from highest to lowest and plotted against the cumulative percent biomass or percent abundance (Fig. 1). Plots in which the k-dominance curve for biomass falls above the curve for abundance are indicative of communities in which the most abundant fauna are large, slower growing species. These communities are indicative of relatively unstressed conditions. Plots in which the curve for abundance falls above the curve for biomass represent communities in which the most abundant species are small and rapidly growing. These are more typical of disturbed or eutrophied communities (1). No large differences were apparent between the k-dominance curves of abundance and biomass in the upper portion of either estuary. In both the middle and lower portions of the estuaries, the eval- uation suggests that Childs River, with its more urbanized wa- tershed, is more impacted by nutrien
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Keywords: ., bookauthorlilliefrankrat, booksubjectbiology, booksubjectzoology
