ABSTRACT
The term ‘built environment’ is not confined to architecture and buildings but also includes their surrounding environment. From an ecological point of view, buildings are only the man-made subsystems that interact with their environments in a complex manner. To understand and simplify the complexity, some conceptual models have been developed. For example, Yeang (1995) developed a model to interpret the interrelationships between physical and biological constituents in an ecosystem. In his model, structures and buildings are the integrated parts of human communities which interact not only with animal and plant communities but also with climate, geology, soils and hydrologic processes. Yeang believed that, with less interference from human communities, the whole system inclines to be a natural one which can self-maintain and create an inner balance easily. Otherwise the system becomes unstable and faces its downfall when the issues caused by buildings and structures are not solved within the system. On the other hand, to make the man-made system work, a large amount of natural resources should be input from the environment while a similar amount of waste is generated and channelled back to the environment ultimately. The continuous input-output process unavoidably triggers many environmental issues.
