There have been numerous scale created to measure Environmental Identity and below are three of the more common scales.
Environment Identity Scale
Environment Identity Scale (EID) is developed by Clayton (2003) to measure the extent to which people consider nature as part of their self-concept. It contains items on a 5-point Likert scale and respondents are asked to state how much they agree or disagree with the statements.
Part of EID Scale
Scale extracted from: http://www.conpsychmeasures.com/CONPSYCHMeasures/Measures/EID/EID_Scale.docx
Inclusion of Nature in Self
Inclusion of Nature in the Self (INS) is a scale developed by Wesley Schultz (2001). It requires participants to simply choose the circle that best represent their relationship with the natural environment to assess the extent to which an individual includes nature with his or her cognitive representation of self.
Example of INS
Scale extracted from: http://www.conpsychmeasures.com/CONPSYCHMeasures/Measures/INS/INS_Scale.docx
Connectedness to Nature Scale
Connectedness to Nature Scale (CNS) measures the emotional connectedness of participants to the natural world. It was created by Mayer and Frantz in 2004. This scale contains items on a 5-point Likert scale to measure the extent an individual feel part of natural is emotionally connected to them.
Part of CNS
Scale extracted from: http://www.conpsychmeasures.com/CONPSYCHMeasures/Measures/CNS/CNS_Scale.docx