Arocena R
Sección Limnología, Facultad de Ciencias, Montevideo, Uruguay.
Rev Biol Trop. 1996 Aug;44(2A):659-71.
Macrozoobenthos composition and abundance of an organic polluted stream (A. Toledo, Uruguay) are compared among sites of control (C), degradation (D) and recuperation (R), which were seasonally sampled. Water ionic composition, conductivity, pH, temperature and COD were not different among sites, while oxygen, and BOD did show significant differences. Benthos was more abundant in R mainly due to Heleobia spp. Oligochaetes were dominant in C and D, with Branchiura sowerbyi only in C and Limnodrilus hoffmeisteri in D. Hirudinea, mainly Gloiobdella michaelseni, occurred almost only in R. the richness of taxa was higher in R, but its high abundance of Heleobia spp. and Sphaeridae leads to the lowest diversity, which was higher in C than D, and in warm than in cold seasons for these two sites. The logarithmic distribution model shows communities of low evenness in all sites.
对乌拉圭托莱多一条受有机污染河流的大型底栖动物的组成和丰度，在对照点（C）、退化点（D）和恢复点（R）进行了比较，这些点进行了季节性采样。各点之间的水离子组成、电导率、pH值、温度和化学需氧量没有差异，而氧气和生化需氧量则显示出显著差异。底栖动物在R点更为丰富，主要是由于赫勒螺属。寡毛纲动物在C点和D点占主导地位，苏氏鳃蛭仅在C点出现，霍氏水丝蚓在D点出现。蛭纲动物，主要是米氏球蛭，几乎只出现在R点。分类单元的丰富度在R点较高，但其赫勒螺属和球蚬科的高丰度导致了最低的多样性，C点的多样性高于D点，且这两个点在温暖季节的多样性高于寒冷季节。对数分布模型显示所有点的群落均匀度都很低。
