Wednesday, April 04, 2007 Osmeña: The ultimate sink By Antonio V. Osmeña Estatements
THE seas surrounding the islands of Cebu are the ultimate sink for natural and human wastes. Water used and consumed in homes, factories, commercial establishments and farms flow into rivers, which eventually empty into the ocean.
In other countries, wastes are loaded on barges and dumped directly into the ocean. Although some forms of ocean pollution, like Polychlorinated Biphenyls, are global, the major pollution problems of the oceans are around its edges—the estuaries, wetlands, bays and harbors, industrial centers and mouths of polluted rivers.
Fortunately, the vastness of ocean waters and their constant mixing dilute and disperse many types of waste to harmless levels. Other wastes are broken down and recycled by natural chemical cycles in ocean ecosystems.
Marine life has also proved to be more resilient than some scientists expected. Although the ocean can dilute and break large amounts of sewage and some types of industrial waste—especially in its deep areas— its capacity to do so has limits.
The sheer magnitude of the discharges, especially near the coasts, can overload these natural purifying systems. In addition, these natural processes cannot readily degrade many of the plastics, pesticides and other synthetic chemicals.
To illustrate, the island of Mactan’s coastline during the early 1950s was teeming with marine life. However, today, they are all gone due to ocean pollution. The rivers and creeks in Metro Cebu are filled with all kinds of pollutants, including human wastes which eventually empty into the ocean as rainwater brings them there.
The pristine and sandy shores of Talisay and Liloan in the early 1950s have now become degraded due to uncontrolled emptying of domestic wastes into the ocean.
An estimated 60 percent to 80 percent of the commercially valuable species of saltwater fish, mollusks and shellfish depend on the estuarine zone for food in some stage of their lives. They also need them as spawning grounds or nurseries for their young.
Thus, filling in or damaging the productivity of estuarine zones destroys a major source of protein and affects the livelihood of millions of people.
Estuaries are thin, fragile zones along coastlines where freshwater streams and rivers meet and mix with salty water. The estuarine zone, representing less than 10 percent of the total ocean area, contains 95 percent of all sea life.
Sunlight can penetrate the waters in this shallow zone, allowing photosynthesis to occur for the phytoplanktons.
These plants support zooplanktons and bottom-feeding invertebrates, like shellfish, which in turn, support the larger fish and add to our food supply.
Rivers and creeks that have become dumping grounds in Metro Cebu. In the early 1900s, Cebu City’s Pagina river had its estuarine from the coastlines of Pasil, Lutaos, Suba, Sawang Calero up to Duljo. Today, the river is hopelessly polluted and the sandy shore of Pasil is filled with settlers.
Unfortunately, protection plans are hampered because of the conflicting goals of the coastal municipalities and cities sharing the estuarine zones. The coastal zone management should ensure that the public has free and unrestricted access to shorelines and beaches, by allowing them to have a voice on how coastal lands will be used and by encouraging private foundations to buy and protect the most critical areas until they can be taken over by the government.
