Quantitative photography for rapid, reliable measurement of marine macro-plastic pollutionJoseph Razzell Hollis, Gabrielle Henderson, Jennifer L. Lavers, Edward Rea, Valeriya Komyakova, Alexander L. Bond
- Plastics are now ubiquitous in the environment and have been studied in wildlife and in ecosystems for more than 50 years. Measurement of size, shape and colour data for individual fragments of plastic is labour-intensive, unreliable and prone to observer bias, particularly when it comes to assessment of colour, which relies on arbitrary and inconsistently defined colour categorisations. There is a clear need for a standard method for data collection on plastic pollution, particularly one that can be readily automated given the number of samples involved.
- This study describes a new method for standardised photography of marine plastics in the 1–100 mm size range (meso- and macro-plastics), including colour correction to account for any image-to-image variation in lighting that may impact colour reproduction or apparent brightness. Automated image analysis is then applied to detect individual fragments of plastic for quantitative measurement of size, shape, and colour.
- The evidence shown in this study should strongly encourage the uptake of this method for cataloguing macro-scale plastic pollution, as it provides substantially higher quality data with accurate, reliable measurements of size, shape and colour for individual plastics that can be readily compared between disparate datasets.