GEL 16 Lecture Notes - Lecture 17: Biomagnification, Pacific Ocean, Bioavailability
Document Summary
Point source pollution: pollutants discharged directly into seawater from discrete sources (sewage pipes) Non point source pollution: pollutants acquired as water flows across land towards the sea. Plastic is made from petroleum (oil found beneath earth"s surface/fossil fuel) Limited amount of times plastic can be recycled. Bio-degradation: compounds broken down into simpler, natural compounds by biological agents. Photo degradation: compounds broken down into smaller parts of the same polymer by uv radiation. Over time plastics become so small we can"t collect them but may still cause harm to oceans. Microplastics: plastic items less than 5 mm in size. Pros: serves many purposes, light and durable, serves medical purposes. Cons: is made of non renewable resource, non biodegradable, can"t be indefinitely recycled. Gyre: any large rotating system of ocean currents. Scientists study how plastic collects in gyres and see how plastic concentrations change over space and, with more data, over time. Direct effects of plastics on organisms in oceans:
