Assessment and quantification of anthropogenic pressures on Posidonia oceanica (L.) Delile 1883 meadows in the central Algerian coast

The present study aims to define a straightforward and cost-efficient method for evaluating the impact of human activities on the Posidonia oceanica meadows along the Algerian coast. employing a combination of visual and quantitative methods. The study evaluates multiple pressures including urbanization. industrial activity. port proximity. fishing activity. wastewater discharge and the presence of invasive species. Satellite imagery was used for the visual assessment and quantitative data were collected from various sources such as governmental websites. academic databases. and administrative bodies. for the calculation of an integrated exposure indexes. These indexes standardize the pressure values to facilitate comparison and estimation of total human impact. Pearson’s coefficient. were applied to correlate these pressures with the ecological status of Posidonia oceanica meadows represented by the ecological quality ratio values of the multiparametric index Posidonia Rapid Easy Index. The findings reveal a high significant correlation between the assessment of anthropogenic pressure using the visual approach and the ecological status of Posidonia oceanica meadows. This visual approach provides a detailed picture of the anthropogenic pressures affecting Posidonia oceanica meadows than other approaches. The absence of more relevant and updated data that can adequately reflect the human impact on these marine ecosystems can explain the low correlation obtained with the quantitative approach.