ENVIRONMENTAL CONSEQUENCES OF DEVELOPMENT
Although Malaysia's development achievements over the last 25 years have been impressive, such rapid pace of change has not been without its detrimental effects on the natural environment. It is not feasible to build new hydroelectric dams, airports and city conurbations, for example, without incurring physical change. But, to avoid extensive and unpalatable destruction of the environment and to demonstrate real progress, any new developments should ideally improve materially on what they destroy. Developing, and protecting, an environment that can be viably sustained into the foreseeable future is precisely what has not been the modern pattern of development in Malaysia. Despite all the improvements development has brought to the material lives of Malaysians, almost all aspects of the environment have been affected by development activities. These range from deforestation to air and water pollution, from erosion and siltation to the dangerous discharge of hazardous and toxic wastes.
The area of natural forests in both the Peninsula and Sabah and Sarawak is fast being depleted. Major causes include large-scale land development schemes, dam construction, mining, shifting cultivation and commercial logging. These activities also destroy, or threaten to diminish, the nation's biodiversity. Malaysia's closed canopy forests contain more than 50 per cent of the world's total plant species and about 1,000 species of vertebrates and anywhere between 20,000 and 80,000 invertebrates, many of which are indigenous. Soil erosion is closely associated with deforestation and vegetation clearance on hillslopes. This is best illustrated by erosion scars on steep road cuttings which can be observed alongside Malaysia's major highways.
Water and marine pollution are also closely related to many development activities. Major sources include organic wastes (sewage and animal wastes), silt from erosion and discharges from industries. Logging activities contribute to the siltation of rivers and the pollution of watercourses. Rivers which run through urban industrial areas contain heavy metals such as mercury, lead and zinc, and in many locations exceed World Health Organization standards. In coastal areas, oil and grease and suspended solids are major contaminants.
Air pollution is an additional problem, especially in urban industrial areas. Major sources include industries and motor vehicles. Kuala Lumpur and the Klang Valley are among the worse affected areas, with prolonged haze episodes occurring during dry months. Toxic and hazardous wastes are unavoidable by-products of industrialization. Their swift, safe and efficient disposal and greater enforcement of anti-pollution regulations should be national priorities.
