“…Scholars utilized different variables as an indicator of environmental degradation such as CO 2 emission (Ang, 2007;Atici, 2009;Apergis and Payne, 2009;Jalil and Mahmud, 2009;Acaravci and Ozturk, 2010;Marrero, 2010;Guangyue and Deyong, 2011;Zilio and Recalde, 2011;Pao and Tsai, 2011b;Kim et al, 2011;Saboori et al, 2012;Ozturk and Acaravci, 2013;Cho et al, 2014;Farhani et al, 2014;Apergis and Ozturk, 2015; and so forth), Biological oxygen demand emissions (Apergis and Payne, 2010), and Ecological footprint (Al-mulali et al, 2015). In addition, a number of variables were used as main determinants of environmental degradation as such as GDP growth and its square (Ang, 2007;Atici, 2009;Apergis and Payne, 2009;Jalil and Mahmud, 2009;Acaravci and Ozturk, 2010;Marrero, 2010;Apergis and Payne, 2010;Lee et al, 2010;Lean and Smyth, 2010;Guangyue and Deyong, 2011;Zilio and Recalde, 2011;Pao and Tsai, 2011a;Kim et al, 2011;Shahbaz et al, 2012;Saboori and Sulaiman, 2013;Chandran and Tang, 2013;Kohler, 2013;Robalino-López et al, 2014;Al-mulali et al, 2015;Apergis and Ozturk, 2015; and so forth), energy consumption (Ang, 2007;…”