Spatial and Temporal Patterns of Riverine Plastic Waste Inputs to the Ocean in Sri Lanka: Integrating Waste Management Archetypes and Hydrological Drivers

Abstract

Understanding the plastic waste input to the ocean is a critical study to keep the Indian ocean clean, The research problem addressed in this study is to quantify, analyze, and visualize the spatial and temporal patterns of plastic waste inputs from river mouths into the ocean in Sri Lanka. This involves integrating geospatial and tabular data on riverine plastic pollution, identifying highcontributing river mouths, examining seasonal trends, and relating these patterns to waste management archetypes. The ultimate goal is to inform targeted interventions for reducing plastic leakage from land-based sources into marine environments. This research would analyze the spatial distribution and seasonal trends of plastic waste entering the ocean from Sri Lankan rivers, using geospatial and statistical methods. It would also examine how different waste management archetypes contribute to plastic leakage, and assess the influence of hydrological variables (e.g., runoff) on plastic input variability. The findings could inform targeted interventions for reducing plastic pollution at critical river mouths and improving waste management strategies. The research integrates Geographic Information Systems (GIS), remote sensing data, hydrological analysis, and field sampling to identify high-risk zones. We have employed Getis-Ord Gi* and Kernel Density Estimation (KDE) to identify statistically significant clusters. The primary results show strong correlations between plastic accumulation and anthropogenic activities including urban runoff, tourism, and inadequate waste management. The findings provide an evidence-based framework for targeted interventions and sustainable policy development.