International Journal of Marine Science, 2024, Vol.14, No.1, 21-28 http://www.aquapublisher.com/index.php/ijms 23 Figure 2 Glacier melting caused by global warming (Image source: https://www.nipic.com/show/18662533.html) 1.2 Direct impact of climate change on the ocean Climate change has direct and far-reaching effects on the oceans, manifested not only in the rise of sea water temperature but also in various aspects such as ocean acidification and sea level rise. The emission of greenhouse gases results in an increase in Earth's temperature, and approximately 70% of this additional heat is absorbed into the oceans. This leads to an elevation in sea water temperature, affecting not only the surface waters but also deeper layers of the ocean. The warming of seawater has widespread implications for marine ecosystems. The temperature rise has particularly pronounced effects on coral reef ecosystems. Elevated temperatures can induce corals to expel symbiotic algae, leading to coral bleaching, which poses a threat to the survival of many coral reef organisms. With the increase in sea water temperature, the distribution range of some marine organisms may expand, while others may be at risk. Changes in marine ecological niches and food chains may occur as elevated temperatures affect the survival and reproductive capabilities of different species, potentially disrupting the balance of ecosystems. Climate change also results in ocean acidification, another significant direct impact. Carbon dioxide (CO2) emissions, in addition to contributing to the greenhouse effect, dissolve in seawater, forming carbonic acid. This makes seawater more acidic, severely affecting marine organisms and ecosystems (Paul, 2018). Acidification poses a threat to the construction and maintenance of coral reefs. Most corals in coral reefs rely on calcification to form their hard skeletons, but acidification reduces the concentration of carbonate ions in seawater, making coral growth challenging and leading to coral reef degradation. Acidification makes it more difficult for them to form shells, thereby threatening the survival of these organisms. 2 Plastic Waste Distribution and Dispersion in the Ocean 2.1 Sources of plastic waste Plastic waste originates from a diverse range of sources, including plastic bags, disposable cutlery, straws, plastic bottles, packaging cups, and boxes. These products are often used for short periods and then discarded, becoming common sources of plastic waste. Various goods, food items, and everyday products are typically packaged in plastic materials such as plastic bags, foam plastics, plastic sealing bags, cling film, and more. A significant amount of packaging waste comes from consumer product packaging. Plastic products include food and beverage containers, cosmetic bottles, detergent bottles, and the like. These plastic containers are usually discarded after use, contributing to plastic waste. Clothing, shoes, and household items made from synthetic fibers release tiny plastic fibers, which may enter water bodies through washing, becoming a source of marine plastic waste. In industrial manufacturing processes, plastic waste, rejected products, and defective items can generate substantial plastic waste if not properly managed, posing environmental issues. Large quantities of plastic packaging waste generated by commercial and industrial units, including transport packaging, trays, films, bags, and more. Improper waste disposal, accumulation of garbage, failure to recycle or inadequate recycling also contribute to the accumulation of plastic waste.
RkJQdWJsaXNoZXIy MjQ4ODYzNA==