Warming influences CO2 emissions from China's coastal saltmarsh wetlands more than changes in precipitation

Frequent water table depth fluctuations due to warm-dry conditions can significantly trigger carbon emissions from coastal salt marshes

Coastal salt marshes are crucial for blue carbon storage, but their carbon emission patterns are uncertain due to frequent fluctuations in water table depth (WTD). This uncertainty is caused by the simultaneous impacts of global warming and rising sea levels. This study assessed carbon emission patterns in the Yellow River Delta under different hydrological fluctuation modes (high fluctuation of WTD scenario (HF-WTD) and low fluctuation of WTD scenario (LF-WTD)) and hydrothermal conditions through a 3-year in-situ observational experiment. The region is typically impacted by climatic warming and drying. Results showed that: (i) Intra-annual WTD fluctuations promote CO2 emission flux, but they are not significantly related to the rising or falling state. On the other hand, methane (CH4) emission flux are dominated by WTD that are more favourable when WTD continues to rise. (ii) The transition point for carbon emission flux with respect to WTD is between -51 cm and -54 cm, and is not affected by the fluctuation pattern of the WTD. (iii) CO2 is more sensitive to temperature when the WTD fluctuates violently and is high, while CH4 is more sensitive to temperature when the WTD is stable and low and the temperature is <17.71 °C. (iv) In the scenario of high-frequency WTD, the variation in WTD, combined with the sharp temperature change, contributes to the peak of CO2 emission flux. In contrast, in the low-frequency WTD scenario, WTD fluctuations, coupled with extreme temperature fluctuations, contribute to the peak of CH4 emission flux. The conclusions suggest that the high and frequently fluctuating WTD caused by climate warming and drying, as well as rising sea levels, will significantly increase CO2 emission flux from coastal salt marsh wetlands. This increase in emission flux will be detrimental to the blue carbon function of coastal wetlands.

Dynamic role of clean energy and sustainable economic growth in coastal region: Novel observations from China

China's coastal region is the major geographical unit for the future development of China's industrial sector. The transformation of basic structure to high-class development in China's coastal places is a significant tool for promoting the changes related to quality, power and efficiency in regional economic development. In the 21st century, environmental and energy issues have increased worldwide, and challenges related to environmental pollution, energy crises, and ecological imbalances have emerged. To climate change and energy utilization, the sustainable progress of clean energy is the new route of future energy development. Based on China's non-polluting energy growth process in the last ten years, this article explores China's clean/green energy policies and economic growth development plans. Clean energy utilization is crucial for sustainable development in the context of high-quality economic growth and climate change. However, the monetary evolution and carbon emission are not investigated whole from the clean energy aspects. Using Wind energy sources as the acceptable variable, this paper employs threshold regression and impulse functions to assess the energy consumption and economic growth on carbon emission in 30 Chinese provinces over the 2000 to 2020 period. The Deep Belief Network (DBN) model predicts wind energy utilization and efficiency. The results show that economic development and carbon emissions are connected. Further, growth influences promote the offset of carbon emissions. Green innovation alters the nexus of carbon emissions, and China's economy reduces carbon usage. It provides the decision-making policies for clean energy development.

New urbanization and carbon emissions intensity reduction: Mechanisms and spatial spillover effects

The advancement of new urbanization policy (NU) and the attainment of double carbon targets play pivotal roles in facilitating high-quality economic development in China. This paper conducts a comprehensive analysis of the mechanism and spatial spillover effects of NU on carbon emission intensity reduction (CEIR), building upon an examination of the nature of NU and the principles of urban carbon pollution control. The research employs a multi-period difference-in-difference model (DID) to explore the causal relationship between NU and CEIR, using panel data from 278 prefecture-level cities spanning the period of 2006 to 2020. Empirical results demonstrate that the implementation of NU resulted in an 8.4 % reduction in carbon emission intensity (CEI). Furthermore, the analysis of the transmission mechanism reveals that NU stimulates green technology innovation and facilitates the development of industrial agglomeration, thus achieving CEIR. The decomposition of the spatial Durbin model indicates significant spatial spillover effects in the effectiveness of NU, signifying its positive impacts not only within the region but also in generating benefits for surrounding areas. Moreover, the dynamic heterogeneity results indicate that entrepreneurial vitality and urbanization rate exhibit dynamic effects on the policy's CEIR effect, both displaying nonlinear enhancement curves. Based on this, the policy implications of this paper include: The government should enhance regional coordinated governance to address carbon emissions pollution in alignment with China's NU. This can be accomplished by effectively harnessing the driving role of green innovation and industrial agglomeration. Additionally, the local government can actively create an entrepreneurial atmosphere and expedite the urbanization process in order to support NU in the implementation and achievement of CEIR.