Nonlinear effects of marine economic growth and technological innovation on marine pollution: Panel threshold analysis for China's 11 coastal regions.

Conventional wisdom has it that marine economic growth and technological innovation help to reduce pollution of the oceans. Few studies, however, have examined whether the relationship is nonlinear and to what extent the effects have been realized. To fill this gap, this study takes 11 coastal regions of China during the period 2000–2016 and, using the panel threshold model, examines the nonlinear effects of per capita gross ocean product (GOP) and marine patents on marine pollution as represented by the quantity of industrial wastewater discharged directly into the sea. The results reveal that the increase in per capita GOP strongly promotes marine pollution across the three phases of panel threshold model, but the degree of influence is gradually declining, implying that China is still located in the first half of the Environment Kuznets Curve (EKC), before the peak. Thus, a negative correlation of the GOP–pollution nexus can be expected if current trends continue, which suggests that the development of the marine economy may alleviate ocean environmental pressures. As for marine patents, no significant correlations in the low- and mid-level phases were found, but a strong impact by marine patents on pollution is shown in the high-level phase, indicating that the accumulation of technological innovation related to the marine economy is playing an increasingly important role in reducing marine pollution. Finally, the numbers of provinces/municipalities in the three phases have been identified. Several important policy implications for development of the marine economy are highlighted. • We use threshold model to explore effect of marine growth and patents on pollution. • Marine growth in China is still in the first half of Environment Kuznets Curve. • Marine patents have begun to significantly alleviate marine pollution. • Numbers of regions in the three threshold regimes have been identified. • We are the first to account for nonlinear marine pollution processes in China. [ABSTRACT FROM AUTHOR]