This paper consolidates and applies statistical methods to the per-capita carbon dioxide emissions and emissions per unit of the gross domestic product (GDP) data of the World Bank member nations, and presents an analysis of the temporal and geographical sources of carbon dioxide emissions. The results indicate that during the observation period, the countries’ per-capita carbon dioxide emissions and emissions per unit of GDP both displayed evidence of convergence. The global per-capita carbon dioxide emissions are relatively stable, and are converging at a rate lower than that of the emissions per unit of GDP. In terms of per-capita income levels, the total emissions of the mid-tier countries continue to grow, and countries with mid-tier per-capita income levels exhibit higher emissions per unit of GDP than both the low and high per-capita income countries. In terms of location of low- and middle-income countries, Southeast Asia and the Pacific have relatively high emission levels, while the per-capita carbon emission levels and the emissions per unit of GDP for Latin America and the Caribbean, South Asia and sub-Saharan Africa are below the global average. The gap between emission levels across different countries, geographic regions, and income groups continues to decrease.

The trade-off and synergy relationship between ecosystem services (ESs) and human well-being (HWb) in the land-use process has become a research hotspot. The evolutionary process and regional contribution of the accurate quantification of ESs and HWb can provide a reference for government departments to formulate macroeconomic policies. Therefore, this study first constructed an analysis framework to identify the synergistic states/evolutionary stages of the gross ecosystem product (GEP) per capita (PGEP) and gross domestic product (GDP) per capita (PGDP) and the regional contribution of the GEP–GDP synergy of 362 municipal units in mainland China from 2000 to 2015. We did this by employing the Markov transition probability matrix, land use data, and economic data based on satellite remote sensing images. The findings of this study show that (1) the PGEP of the Chinese mainland has a remarkable spatial divergence featuring a higher value in the northwestern Chinese mainland and a lower value in the southeastern Chinese mainland on both sides of the Hu Line during the investigation period; despite the eastern Chinese mainland having a higher PGDP, the PGDP at the national level is distributed in dispersion on both sides of the Hu Line; (2) during the first half of the investigation period, the GEP–GDP synergy in the Chinese mainland was generally in the pseudo-synergy stage or the transition stage from pseudo-synergy to primary/intermediate synergy, while in the second half of the period, the GEP–GDP synergy in the Chinese mainland continued to improve; (3) the GEP–GDP synergy was relatively stable on the Chinese mainland during the investigation period, with 24.28% of the units shifting to a lower or higher level synergy, and the GEP–GDP synergy was more stable in the western and central Chinese mainland, while it was more likely to shift to a higher state in the northeastern and eastern Chinese mainland. This study suggests that the GEP–GDP relationship varies with spatial scales; a hierarchical, multiscale approach is necessary to study and improve both of these relationships, as simply extrapolating policies across single administrative levels may lead to unintended outcomes.

Introduction: Large stocks of “blue carbon” exist in the ecosystems of coastal wetlands. This paper presents a case study of the Chinese city of Yancheng. First, through field surveys and laboratory analysis, changes in the organic carbon (OC) content in typical plant communities throughout the study area are described in detail. Second, an OC burial rate and economic value model is constructed to analyze the composition of the carbon sink values. Outcomes/other: The results are as follows: Of the typical plant communities, Spartina alterniflora has the highest OC content (5.80 g·kg-1), followed by Suaeda glauca (4.78 g·kg-1) and Phragmites australis (3.76 g·kg-1); the contemporary OC sedimentation rates are 2.01, 1.48, and 1.22 cm·yr-1, respectively. Spartina alterniflora communities have the highest annual average carbon sink value ($418.74/ha) in the study area, followed by Phragmites australis ($176.29/ha) and Suaeda glauca ($101.54/ha). Discussion: As a result of both the expansion of the Spartina alterniflora area and coastal erosion, the total OC value since 1987 has displayed two-stage characteristics: it first increased and then decreased. Conclusion: In recent years, the annual average decline in OC value has ranged from approximately $82,100 to $123,100 (reference: the Sweden carbon tax provided by the World Bank, 130$/ton)