Marine ecosystems may include oceans, estuarine, and brackish river ecosystems. These systems vary primarily in their level of salinity and thus in the kind of life that they can sustain.

Oceans have the highest concentration of salinity and can thus support biodiversity found nowhere else on earth. These populations are constantly under attack, however, from point and non-point source pollution, unsustainable fishing and harvesting practices and irresponsible ecotourism.

Estuarine systems are prime victims of industrial pollution. Here the currents are relatively slow, allowing pollutants to linger in the shallows, decimating the estuarine biodiversity. For a classic and appalling example of estuarine pollution please reference the Newmont Minahasa Raya mining company issue in our mineral resources section.

Oceans are the recipients of billions of tons of toxic waste discharge. Though large bodies of water that can diffuse vast volumes of solutes, these pollutants are often released near the shore where the greatest concentration of marine wildlife resides. This wildlife is contaminated before the pollutants have a chance to disperse.

Much of this also results from illegal offshore waste discharge by ships. Theoretically international law prohibits vessels from discharging toxic wastes within seven miles of the shoreline. However, this is rarely, if ever enforced and freely violated. Several of our volunteers have been aboard US, and Australian naval and various merchant marine vessels that disregarded these procedures with wanton blatancy.

Even if this regulation is adhered to, however, the contaminants can still eventually wash ashore, decimating coastal ecosystems.

Another form of illegal offshore dumping is the dumping of hazardous materials or items contaminated therewith. These are detrimental to the marine environment regardless of where they are released. Again, military and commercial vessels and their hands nonchalantly disregard these procedures on a regular basis, as many of our volunteers have sadly witnessed first hand.

Unsustainable harvesting practices include over fishing/harvesting, fish bombing, the anchoring of fishing boats in coral reefs, and dredging, to name a few. There is a huge environmental/social dichotomy posed by this issue because many who are guilty of unsustainable practices are poor fisherman seeking to provide an honest living for their families. They must be educated, however, that if these populations are destroyed they will not have any means of livelihood, anyway. There is no easy solution to this dilemma. We welcome any comments or suggestions on this matter .

Irresponsible ecotourism includes the capture of endangered species, contact with coral, anchoring of boats into coral reefs, support of unsustainable harvests, etc. More about responsible and irresponsible ecotourism is discussed in our coral reefs section.