Final answer:
The missing environmental attribute in the question is 'economic'. The DPCI evaluates the interrelations among economic, cultural, and political aspects with the environment, emphasizing the importance of understanding cultural ecology and sustainable development in geography.
Step-by-step explanation:
The environmental attributes considered in the Design Project Cultural Index (DPCI) are economic, cultural, political, impact on the ecology, and impact of the ecology on the project. Understanding the interaction between cultural practices and the physical environment, known as cultural ecology, helps in evaluating such attributes. The DPCI considers how economic and social practices within a culture relate to physical environments and ecosystems, and also how they shape and are shaped by global phenomena such as globalization and sustainable development. In the context of geography, these considerations are crucial for evaluating the relationships between settlements and their environments, including the management and use of renewable and non-renewable resources.