Possible Clues:

• The interaction of a group of organisms with their physical environment
• Unit consisting of a community of organisms and their environment
• Rain forest, e.g
• Environmental concern
• Environmentalist's study
• A green sphere?
• The interaction of organisms with their physical environment
• European comfortable with support in which lives are connected
• English officer network for community in the wild
• Ultimately nice and comfortable bit of shrub for biological set-up