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Achieving environmental sustainability has become a global initiative whilst addressing climate change and its effects. Thus, this research re-assessed the EKC hypothesis in China and considered the effect of hydroelectricity use and urbanization, utilizing data from 1985 to 2019. The autoregressive distributed lag (ARDL) bounds testing method was utilized to assess long-run cointegration, which is reinforced by a structural break. The outcome of the ARDL bounds test confirmed cointegration among the series. Furthermore, the ARDL revealed that both economic growth and urbanization trigger environmental degradation while hydroelectricity improves the quality of the environment. The outcome of the ARDL also validated the EKC hypothesis for China. In addition, the study employed the novel gradual shift causality test to capture causal linkage among the series. The advantage of the gradual shift causality test is that it can capture gradual or smooth shifts and does not necessitate previous information of the number, form of structural break(s), or dates. The outcomes of the causality test revealed causal connections among the series of interest.

While most African economies are primarily sandwiched with the seemingly unsurmountable task of attaining consistent economic growth and unhindered energy supply, the enormous threat posed by environmental degradation has further complicated the economic and environmental sustainability drive. In this context, the present study examines the effect of economic growth, urbanization, electricity consumption, fossil fuel energy consumption, and total natural resources rent on pollutant emissions in Africa over the period 1980-2014. By employing selected African countries, the current study relies on the Kao and Pedroni cointegration tests to cointegration analysis, the Pesaran's Panel Pooled Mean Group-Autoregressive distributive lag methodology (ARDL-PMG) for long run regression while Dumitrescu and Hurlin (2012) is employed for the detection of causality direction among the outlined variables. The study traces long run equilibrium relationships between examined indicators. The ARDL-PMG results suggest a statistical positive relationship between pollutant emissions and urbanization, electricity consumption and non-renewable energy consumption. Dumitrescu and Hurlin (2012) Granger causality test lends support to the long-run regression results. A bi-directional causality is observed between pollutant emissions, electricity consumption, economic growth and pollutant emissions while a unidirectional causality is apparent between total natural resources rent and pollutant emission. Based on these results, several policy implications for the African continent were suggested. (a) The need for a paradigm shift from fossil fuel sources to renewables is encouraged in the region (b) The need to embrace carbon storage and capturing techniques to decouple pollutant emissions from economic growth on the continent's growth trajectory. Further policy insights are elucidated., Competing Interests: Declaration of competing interest The authors declare no conflict of interest., (Copyright © 2019 Elsevier B.V. All rights reserved.)

This study empirically investigates the agriculture-induced environmental Kuznets curve (EKC) hypothesis in an agrarian framework. Annual time series data from 1981-2014 was employed using augmented Dickey-Fuller and the Phillips-Perron (PP) unit root test complemented by the Zivot and Andrews unit root that accounts for a single structural break to ascertain stationarity properties of variables under consideration. For the cointegration analysis, an autoregressive distributive lag methodology and the recent novel Bayer and Hanck combined cointegration technique are employed. For the direction of causality, the Granger causality test is used as estimation technique. Empirical findings lend support for the long-run equilibrium relationship among the variables under consideration. This study also validates the inverted U-shaped pattern of EKC for the case of Nigeria, affirming that Nigeria remains at the scale-effect stage of its growth trajectory. Further empirical results show that foreign direct investment attraction helps mitigate carbon emissions in Nigeria. Based on these results, several policy prescriptions on the Nigeria energy mix and agricultural operations in response to quality of the environment were suggested for policymakers, stakeholders, and environmental economists that formulate and design environmental regulations and strategies to realise the goal 7 of sustainable development (SDG).