Spatial Distribution and Socioeconomic Drivers of Plastic Debris in Mangrove Sediments along the Persian Gulf

Mangrove forests possess high ecological and economic value and provide numerous ecosystem services that sustain the livelihoods of local communities through fisheries and ecotourism. The aim of this study is to assess the number of plastic and non-plastic waste materials disposed of in four mangrove habitats, namely Bidkhun from the Nayband mangroves in Bushehr Province, and in Hormozgan Province the three regions of Tabl, Sohaili, and Gorzin from the Qeshm mangroves, the two regions of Kendal and Hara National Park from the Bandar Khamir mangroves, and the two regions of Kolahi and Tiab from the Minab mangroves. In addition, the study examines the significant relationship between the amount of disposed waste and influencing factors such as population of the sampling area, number of tourists, and the level of fishing activity in each region. This research provides the first integrated spatial and statistical assessment of macro-plastic waste dynamics across multiple mangrove habitats in southern IranThe average percentage of plastic per square meter in the Bidkhun, Hara Khamir, Kendal, Tabl, Sohaili, Gorzin, Tiab, and Kolahi mangroves was calculated as 13.7, 2.3, 2.5, 6, 7.5, 5, 3.2, and 3, respectively. According to the results, the highest and lowest amounts of plastic waste were recorded in the Bidkhun and Kendal mangroves, respectively. The population growth following the establishment of the South Pars complex and the influx of migrants, along with the excessive use of disposable containers for food distribution in the numerous companies located in Assaluyeh, have led to increased deposition of plastic waste in the sediments of these sensitive ecosystems. In contrast, the lower population, limited tourism, and high environmental awareness of the local communities are among the reasons for the reduced amount of plastic waste in the Kendal mangroves. Statistical analyses revealed that among the examined influencing factors, tourist population showed the most significant correlation with the amount of plastic and non-plastic waste in these regions, based on Pearson correlation and multiple regression analysis results.