In 1938, B.F. Skinner coined the term operant conditioning; it means roughly the changing of behavior by the use of reinforcement which is given after the desired response. The typical example sets a rat in a cage with a lever: after a couple of random tries, the rat learns quickly that pressing the lever will get him food, because his behavior gets reinforced by the reward he earns.
The insights gained thanks to Skinner’s experiments, have a range of implications for environmental behaviors. Think about persons deciding to use public transports instead of private cars… in Italy for instance, they would typically end up spending more time in transports, and so the green behavior is not rewarded, and may therefore implicitly be discouraged.
This is an important aspect to consider for public institutions when designing policies and incentives willing to promote environmental-friendly behaviors.