As such, the study follows the structure of the overall approach taken in the present study with the use of (part of) the DPSIR framework. The OECD study acknowledges the complexity of the relations between the state of the environment and the ensuing state of the biodiversity due to the multidimensionality of the physical environment, the multitude of ecosystems and the multiple pressures that have an effect on their state. Monitor the effects of response policies issued by society.