Gyamfi Bright Akwasi, Adedoyin Festus Fatai, Bein Murad A, Bekun Festus Victor
Faculty of Economics and Administrative Sciences, Cyprus International University, Via Mersin 10, Nicosia, North Cyprus, Turkey.
Department of Accounting, Economics and Finance, Bournemouth University, Fern Barrow, Poole, BH12 5BB, UK.
Environ Sci Pollut Res Int. 2021 Feb 26. doi: 10.1007/s11356-021-12967-x.
The environmental Kuznets curve (EKC) hypothesis is of great importance to understanding the relationship between economic activity and environmental degradation. Given the current wave of climate change and environmental crisis traced to rising environmental pollution from economic activities, it has become important to investigate the impact of economic expansion on the environment especially in the emerging-7 countries that are responsible for a large amount of global economic activity. This study investigates the N-shaped EKC for the E-7 countries using data spanning the period 1995-2018. The study employs the use of PMG-ARDL estimator and heterogeneous causality tests to establish the long run and short run and direction of causality respectively regarding the variables of interest. According to study empirical results, the long-run results fail to confirm the presence of an N-shaped EKC in the emerging 7 countries but rather confirms the existence of an inverted U-shaped EKC in the study countries. While renewable energy and non-renewable energy have a positive and significant relationship with CO emissions, short run results show that there is no significant relationship between economic expansion, renewable energy, non-renewable energy and CO emissions. Causality tests showed a bi-directional causality between GDP- and GDP-squared and a uni-directional causality from CO emissions to GDP-cubed, non-renewable energy and CO emissions, renewable energy, and CO emissions. The study suggests increased use of renewable energy to mitigate pollutant emissions in the E-7 countries.
环境库兹涅茨曲线（EKC）假说对于理解经济活动与环境退化之间的关系至关重要。鉴于当前气候变化和环境危机浪潮可追溯到经济活动导致的环境污染加剧，研究经济扩张对环境的影响变得尤为重要，特别是在那些承担大量全球经济活动的新兴七国。本研究利用1995年至2018年期间的数据，对新兴七国的N型环境库兹涅茨曲线进行了研究。该研究采用PMG-ARDL估计器和异质性因果检验，分别确定了有关感兴趣变量的长期和短期因果关系及其方向。根据研究实证结果，长期结果未能证实新兴七国存在N型环境库兹涅茨曲线，而是证实了研究国家存在倒U型环境库兹涅茨曲线。虽然可再生能源和不可再生能源与碳排放存在正相关且显著的关系，但短期结果表明经济扩张、可再生能源、不可再生能源与碳排放之间不存在显著关系。因果检验显示，GDP与GDP平方之间存在双向因果关系，碳排放与GDP立方、不可再生能源与碳排放、可再生能源与碳排放之间存在单向因果关系。该研究建议新兴七国增加可再生能源的使用，以减轻污染物排放。
