From The Power of Identity (The Information Age: Economy, Society and Culture, Volume II), pp 112-113:

By environmentalism I refer to all forms of collective behavior that, in their discourse and in their practice, aim at correcting destructive forms of relationship between human action and its natural environment, in opposition to the prevailing structural and institutional logic. By ecology, in my sociological approach, I understand a set of beliefs, theories, and projects that consider humankind as a component of a broader ecosystem and wish to maintain the system’s balance in a dynamic, evolutionary perspective.

In my view, environmentalism is ecology in practice, and ecology is environmentalism in theory . . .

From The Power of Identity (The Information Age: Economy, Society and Culture, Volume II), p 133:

The ecological approach to life, to the economy, and to the institutions of society emphasizes the holistic character of all forms of matter, and of all information processing. Thus, the more we know, the more we sense the possibilities of our technology, and the more we realize the gigantic, dangerous gap between our enhanced productive capacities, and our primitive, unconscious, and ultimately destructive social organization.