Spatio-temporal evolution and convergence analysis of China's land economy and marine economy green development synergy

The green development coordination of land economy (LE) and marine economy (ME) is an inevitable choice to respond to the requirements of sustainable development. This paper measures the level of LE and ME green development synergy in China from 2010 to 2023, and further analyzes the regional differences and convergence characteristics in coordination by using Dagum Gini coefficient method and convergence model. The research shows that LE and ME green development synergy level in all regions has risen to good coordination. The main source of the difference of LE and ME green development synergy has changed from hypervariation density to inter-regional differences, and the internal difference of southern marine economic circle is the largest. Only the northern marine economic circle exists $\sigma$ convergence in stage 1, and it maintains stable $\beta$ convergence with coastal area, which is affected by different factors in different periods. Therefore, make policy recommendations.