Forest policy in the city

Idea of a law which would impose that:

1. 51% of the land area in cities should be covered by forest area. This percentage could be measured by satellite imagery. Any development taking place would not be allowed to overcome the 51% rule. Concern about underground constructions?



2. Or as an alternative
   1. 1/3 of the city land area should be covered by forests and the soil should remain in natural condition
   2. 1/3 of the city land area should be covered by vegetation, underground constructions can be put in place, providing there is at least 50 cm of soil on top of them
   3. 1/3 of the city land area can be covered with any type of artificial construction such as tar roads and concrete buildings.