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Pollution: An issue that can be prevented

The GBO-3 aptly described that pollution loading from nutrients (nitrogen and phosphorous) poses an imminent threat to terrestrial, inland water and coastal ecosystems1. This is particularly true in a region where agriculture is a key economic sector and farming practices have moved towards intensification of food production. The introduction of the Green Revolution Program has enabled many countries in the region to meet their expanding demand for food. Along with this program, however, is the introduction of inorganic inputs such as fertilizers and pesticides, which later were realized to have significant environmental and health impact. As a surrogate indicator of how much anthropogenic nitrogen entered into the agro-ecosystem of ASEAN, the per capita consumption of fertilizer is shown as Table 1.  

Table 1. Per capita consumption (in nutrients) of NPK fertilizers in the ASEAN region, 1990-2008.

The implications of the intensive use of inorganic fertilizers and pesticides in many of the water bodies in the region are quite serious. Rice farming generally involves irrigation and the flooding of paddies. This practice opens up vast pathways for nitrogen and phosphate deposition through run-offs that end up in most water bodies especially the river systems and freshwater lakes. A number of countries are already showing a decline in river quality over recent years owing to rapid urbanization, industrialization and agricultural intensification. In Thailand, river quality showed deterioration between 2005 and 2007. The number of rivers classified as poor increased from 29 per cent in 2005 to 48 per cent in 2007. Indonesia is a similar case.  In 2007, 27 per cent of the 30 rivers monitored were found to be polluted. A year later in 2008, 54 per cent of the 33 rivers monitored were polluted2. In some ASEAN Member States, eutrophication of some of their water bodies has been reportedly characterized by algal blooms: a clear indication of excessive nutrients that stimulate excessive plant growths. Such manifestations have dire impacts on the biodiversity of these ecosystems as they create ecological imbalances.
It must be stressed that the spread of nutrient pollution is not confined to freshwater ecosystems. Coastal and marine areas are equally affected as observed recently and have become a huge challenge for many states. Over the past decade, there have been frequent reports of “red tide” occurrences – a manifestation of excessive nutrients in coastal zones that leads to toxic outbreaks of paralytic shellfish. The impacts of such outbreaks have sometimes been devastating for many fisher folks whose livelihood is solely dependent on seafoods. Similarly, various human activities have increased sediment flows in rivers by about 20 per cent. Mining has also caused heavy toxic pollution, the impacts of which are felt not only on-site but also off-site which are mostly coastal areas: making these areas the “most highly chemically altered ecosystems in the world.” 3

1Secretariat of the Convention on Biological Diversity. 2010. Global Biodiversity Outlook 3, Montreal.

 2ASEAN. 2009. Fourth ASEAN State of the Environment Report 2009.
 3Millennium Ecosystem Assessment. 2005. Coastal Systems.  Accessed on 18 August 2010 at http://www.millenniumassessment.org/documents/document.288.aspx.pdf.
ASEAN Centre for Biodiversity. 2010. ASEAN Biodiversity Outlook: Pollution - An issue that can be prevented. pp. 94. Los Banos, Laguna, Philippines. 2010.