Fig. 3 in The Singscore: a macroinvertebrate biotic index for assessing the health of Singapore's streams and canals

Fig. 3. Non-metric multidimensional scaling (NMDS) ordination based on a Bray-Curtis matrix of dissimilarities calculated from presence-absence data illustrating compositional differences in macroinvertebrate communities among the sites. The NMDS gave a good representation of actual community dissimilarities (2-dimensional stress = 0.16) and ANOSIM separated the sites into four relatively distinct groups (ANOSIM, Global R = 0.769, P = 0.001), interpreted as likely water-quality categories (poor: closed circle; fair: open square; good: closed triangle; excellent: open circle). Axes are scaled identically so that sites closest together are more similar in macroinvertebrate community composition than those further apart.