Fig. 2
From: Quality control in public participation assessments of water quality: the OPAL Water Survey
Effect of operator and sample time on ‘Pond health score’. a Frequency of highest ‘Pond health score’ for individual operators, and all operators combined, related to sampling effort (10, 20 and 30 s net sweeps). b Frequency of highest ‘Pond health score’ for all operators combined for each sampling site, related to sampling effort (10, 20 and 30 s net sweeps)