Figure 2.

Composition of flying insects sampled with Malaise traps ((a) proportion of total insect counts) and the diet composition of Tetragnatha montana spiders ((b) proportion of prey detections from DNA metabarcoding) sampled at different stream sites in riparian forests. Stream sites are arranged from low to high chemical pollution and are labelled by their average pesticide toxicity (sum toxic unit) on the x-axis. A less negative sum toxic unit (log scale) signifies a higher toxicity, and a more negative value a lower toxicity. Taxa coloured from red to yellow (top) are terrestrial, blue and purple (bottom) are aquatic and grey (middle) are of mixed origin. Note that in (a), 25 individuals from aquatic families are included in ‘Coleoptera’, and that Empididae were not separated into aquatic and terrestrial groups (‘Empididae Unknown’). Site ‘−0.85’ is only included in (a) as no prey taxa were detected in spiders there.