Fig. 3. Nonmetric multidimensional scaling ordination of presence–absence data for benthic macroinvertebrate taxa in Illinois streams. Graphs represent Axis 1 vs. Axis 2, Axis 1 vs. Axis 3, and Axis 2 vs. Axis 3. The stream groups were determined by cluster analysis (Fig. 2). Correlation coefficients and P values for vectors are listed in Table 4. DRP, dissolved reactive P.