Impacts of marine litter on coastal and marine benthic ecosystems

Marine litter has been identified as one of the greatest threats to sustainability of aquatic ecosystems. The litter in the coastal and marine habitat can be those transported from the intertidal zone, terrestrial region through tidal waters, storm-water, wind, sewage and rivers, or it can be those directly deposited on the beaches or dumped into the aquatic systems by human interactions. About 50% of plastic marine litter is composed of low-density polymers like polyethene - PE and polypropylene – PP which readily sinks and reaches the benthic ecosystem where it can be trapped in hard rocky structures. Different items like plastic, rubber, glass, metal and other non-biodegradable items contribute to marine debris and UNEP has provided a code for categorizing each of these items. The dominant litter in each area differs, but in most areas, plastic has been found to be the major litter. The tiny micro-plastics have spread into different benthic realms of the coastal and marine eco-systems and in some locations even very high concentrations are observed. The impacts of marine litter on the benthic ecology and on the marine fauna are discussed briefly