Dense gas spectroscopic ratios versus radius in different morphological environments. Similar to Fig. 6 (left panels), but separately for each environment (compare with right map in Fig. 3). The lighter markers denote low-significant (S/N < 3) data. The grey solid line shows the trend of the spectral stacks as in Fig. 6 (red markers). The coloured lines indicate the stacked measurements of the respective environments taken over all CO detected data (i.e. including HCN non-detections) in the respective environment.