The difference between "green space" and "green infrastructure"

Found on the City of Lansing's website for DesignLansing, its Comprehensive Plan process. 

What’s in a Name?

“The term green infrastructure was selected to emphasize its difference from traditional conservation practices and the need to change several popular perceptions about green space planning and protection.  Where-as green space is often viewed as something that is nice to have, the term green infrastructure implies something that we must have.  Protecting and restoring our nation’s natural life support system is a necessity, not an amenity. 

• Where-as green space is often thought of as isolated parks, recreation sites or natural areas, the term green infrastructure emphasizes interconnected systems of natural areas and other open spaces that are protected and managed for the ecological benefits they provide to people and the environment.
• Where-as green space is often viewed as self-sustaining, the term green infrastructure implies something that must be actively maintained and at times restored.” 

From:
Green Infrastructure:
Smart Conservation for the 21st Century
Mark A. Benedict, Ph.D.
Edward T. McMahon, J.D.www.sprawlwatch.org