our precious coasts - marine pollution, climate change and the resilience of coastal ecosystems

Abstract

Climate change is seriously impacting the world’s marine ecosystems.

Massive coral bleaching episodes have impacted the function of the reefs and increased rates of mortality. Coral reefs support over one million plant and animal species and their economic value is projected to more than US $ 30 billion annually. Extreme climatic conditions, however, are most likely to increase in the future with current climate scenarios. Projected increases in carbon dioxide and temperature exceed the conditions under which coral reefs have flourished over the past 500 000 years. Coral reefs are crucial biodiversity hotspots and support both coastal fisheries and tourism in many regions. Coral reefs, however, are in decline in many regions as a result of numerous pressures, including, but not limited to, extreme climate events, unsustainable fishing practices, diseases, sedimentation, and discharge of untreated sewage. Increasing resilience and securing rapid recovery of coral reefs will be essential for the ability of these ecosystems to support coastal fisheries and coastal livelihoods and cultures in the future. However, this resilience and recovery may be seriously impounded by unsustainable coastal infrastructure development and marine pollution from land-based sources. At the current rate of growth, coastal development may impact up to 90% of the tropical and temperate coastlines by 2032 if development continues unchecked. While progress has been made to reduce the discharge and impacts of oil spills and SUMMARY persistent organic pollutants (POP’s), there now needs to be a focus on the largest current threats to the coastal marine environment : untreated sewage and piecemeal coastal development. Over 90% of all the world’s coral reefs are found in the Indo-Pacific region of Asia, but also found here are some of the largest increases and levels of emissions of untreated sewage discharge and coastal marine pollution and development. A drastic increase in the appropriate integrated management of coastlines particularly near marine protected areas is urgently needed. Furthermore, an increase in enforcement and extent of protected coastlines, is urgently needed to secure the future diversity and recovery of coral reefs from climate change. Such combined joint protected areas may form source-“islands” or coral “treasure vaults” for re-colonization of damaged areas. Furthermore, the combined cumulative effects of coastal overfishing, marine pollution and coastal development may impact the long-term productivity of the coastal zone. This, in turn, may lower the capacity of these systems to support human livelihoods in the long-term, This challenge requires effective integrated landuse planning including fisheries, tourism and coastal infrastructure development, as well as proper watershed management further inland.