Hongguang Liu

Carbon emissions in rural areas have increased significantly, resulting in huge emission reduction potential, but research on carbon accounting at the courtyard scale is insufficient. To fill the gap in micro-level carbon management and support the green transformation of rural areas, this study focuses on the planning and design of rural carbon-negative courtyards, aiming to achieve negative emissions in courtyards through carbon accounting and strategic design. This conceptual design was developed for rural areas in Nanjing, Jiangsu Province, China, located in the Yangtze River Delta region with a subtropical monsoon climate. The favorable climatic and ecological conditions provide a suitable context for integrating renewable energy systems and ecological resource management within courtyard spaces. We establish a carbon accounting list and model at the courtyard scale; divide this into five functional zones, planting, residential, breeding, pond, and woodland areas; propose targeted carbon-reduction strategies applicable to courtyards such as photovoltaic and ground-source heat pump technologies; and systematically calculate courtyard carbon sources and sinks. The comprehensive carbon sink of the courtyard in this study removes 2173.27 kg CO₂ per year; the residential area is the main carbon source, accounting for 81.8% of total emissions, while woodland is the core carbon sink, accounting for 11.2% of the total carbon reduction; the emission reduction contributions of PV and ground-source heat pump technologies account for 65.2% and 22.9% respectively. We clarify the spatial types of carbon sources and sinks and propose implementation paths to achieve carbon-negative emissions, such as green buildings and energy optimization. By situating the design in Nanjing, Jiangsu Province, this study provides region-specific support for achieving China’s “dual carbon” goals and promotes the transformation of rural courtyards from carbon emission sources into carbon sink carriers.

Carbon emission reduction is an arduous task that the world needs to face and solve at present and in the coming period, and it is also an important goal in the process of China's economic and social development. It is also an important goal in the process of China's economic and social development. The study of carbon transfer based on the value chain is crucial to the realization of carbon emission reduction and the scientific and reasonable distribution of carbon emission reduction responsibilities. Based on the input-output method, this paper uses the value-based carbon emission accounting method to calculate and analyze the carbon emission transfer characteristics of 30 provinces, autonomous regions and cities in China (excluding Tibet, Hong Kong, Macao and Taiwan) in 2012 and 2017. As many indicators of different aspects as possible are selected, and the problem of covariance between indicators is reduced and eliminated through factor analysis, so as to analyze the key factors affecting carbon transfer. It was found that during 2012–2017, China's carbon emissions as a whole showed a transfer from regions with a higher level of economic development to regions with a lower level of economic development, and from the east to the west, with the net transfer out center of gravity shifting significantly to the north and west. The middle region (MR) has always been the region that transfers out the most carbon emissions, but the net transfer growth rate of some provinces in the MR has decreased more with other regions. During this period, the local resource availability, energy consumption level, and science and technology level had the greatest impact on the change of carbon transfer. Regions with abundant resources but lower levels of science and technology, and higher levels of energy consumption will increase their carbon transfer. The results of this paper are intended to improve the study of carbon transfer along the value chain, and provide a basis for the division of responsibility for carbon emission reduction and the formulation of policies in China.

Carbon emission reduction is an arduous task that needs to be faced and solved globally at present and in the future period, and it is also an important goal in the process of China's economic and social development, and it is crucial to study carbon emissions based on value chain transfer to achieve carbon emission reduction and scientific and reasonable allocation of carbon emission reduction responsibilities. Based on the input-output method, this paper applies the value-based carbon emission accounting method to calculate the carbon emissions, net transfer of carbon emissions and net transfer growth rate of 30 provinces, autonomous regions and cities (excluding Tibet, Hong Kong, Macao and Taiwan) in China in 2012 and 2017, and analyzes the carbon emission transfer characteristics between provinces in China. The results show that during 2012–2017, China's carbon emissions as a whole showed a shift from regions with a higher level of economic development to regions with a lower level of economic development, from the east to the west, and the net transfer out center of gravity shifted significantly to the north and to the west. The main carbon emission transfer in and out of each province and city have changed, and the central region has always been the region with the most transferred carbon emissions, but the net transfer growth rate between some provinces in the central region and other regions has decreased more, and the net transfer growth rate between the northeast and western regions and all provinces and cities in the country, especially those in the coastal region, are larger. The level of economic development and industrial structure contribute the most to the change of net transfer of carbon emissions, and the population factor contributes the least. The results of this paper will provide a basis for improving carbon transfer research in China and guiding the formulation and implementation of carbon emission reduction policies.

The research on the land resources embodied in the inter-regional economic linkages is of great significance for the ecological compensation and sustainable use of the cultivated land. We constructed a model to estimate the agricultural land transfer embodied in inter-regional trade by using the agricultural land footprint model and the multi-regional input–output model. Taking China as an example, using a 2017 multi-regional input–output table and agricultural land and production data, we evaluated the agricultural land footprints embodied in the inter-provincial demand–supply chain in China and explored their characteristics, revealing the balance of income and expenditure that makes up the agricultural land footprint in each region. The results show that: (1) In 2017, China’s total agricultural land footprint was 557.63 million ha². Developed areas such as Shandong, Guangdong, and Jiangsu in the East generally had a greater footprint than the underdeveloped areas in the west. Provinces with more agricultural land do not necessarily have larger agricultural footprints. (2) The Agriculture, Hunting, Forestry, and Fishing industry and the Food, Beverages, and Tobacco industry were the main two sectors that contributed to the agricultural land footprint for each province, accounting for more than 60% of the total agricultural land footprint in China. (3) The embodied agricultural land transfer between regions showed two main directions on the whole: one was from north to south and the other from west to east, reflecting the transfer law of movement from the less developed regions to those that were more developed.

Using actor-network theory (ANT), this paper explores the process and mechanisms of rural space reconstruction in China in the post-urbanization era. In the context of urban–rural integration development in China, villages have become diversified. They are not only the living spaces of villagers, but they are also consumption spaces of urban residents. Through a case study of a typical village in the Yangtze River Delta, this study highlights that the actor-network of rural spatial reconstruction includes heterogeneous actors, such as the village committee, villagers, governments, tourism enterprises, makers, housing, and landscape—among which the Lishui Government is the key actor. Therefore, this paper argues that China’s rural space reconstruction is greatly dependent on external resources such as government policy support or enterprise investment. In the future, promoting public participation will be necessary to realize villages’ endogenous transformation and development.

Embodied carbon emissions research is an important branch of climate change study. Some scholars have noted the value-added chains associated with the carbon emissions embodied in international trade. But they have not covered the global scale and the entire demand-supply chains. This paper tries to investigate this issue and answer how much value-added is gained by countries, especially developing regions that are the main carbon emissions suppliers in the world, and how this value-added changed during 2000–2014, based on the multi-regional input-output table. The conclusions are, on a global average, the value-added gained per unit of carbon emissions embodied in the global demand-supply chain had increased, but it had not brought net value-added to developing regions but instead caused them a net loss of wealth, mainly because developing regions should pay more value-added for their increasingly external demand.

Eco-efficiency has been receiving attention worldwide, and the effective implementation of environmental regulations (ERs) has become crucial to regional eco-efficiency. This paper uses a method combining mixed directional distance function and bootstrapping approach to investigate the spatial and temporal distribution characteristics of eco-efficiency under the constraint of land use carbon emission in China from 2004 to 2016. The nonlinear relationship between ER and eco-efficiency is observed with a panel threshold model. Results from empirical tests reveal that eco-efficiency in China during the study period has an upward trend, and the spatial and temporal distribution of eco-efficiency is unbalanced and concentrated. Technical innovation and land marketization (LM) shows double threshold, whereas industrial structure (IS) has a single threshold effect. LM has a promotional effect on eco-efficiency, which differs in the promotion before and after promotion across the threshold value. Reasonable ER can reduce cost by stimulating the innovation of green production technology and achieves a win-win situation between environment and output. This finding further verifies that the ER for eco-efficiency under the constraint of land use carbon emission conforms to the Porter hypothesis. The effect of ER on eco-efficiency changes from negative to positive with the increase of IS level. Adjusting the ownership structure and increasing the proportion of green achievements in the promotion and assessment of officials are important measures in the upgrading of eco-efficiency.

The national census data during 1995 and 2000 and during 2005 and 2010 are selected in this paper to make an analysis of the spatio-temporal characteristics of the inter-provincial population migration in China. In addition, the general regression model, the extension regression model considering the historical dependent variable and the spatial lag model are established based on the gravity model to make the regression model on China’s inter-provincial population migration over two periods of time. The results show that: (1) the inter-provincial population migration increases rapidly in size with strong geographical proximity; (2) China’s inter-provincial population migration is still in the primary stage of the general process of population migration. In other words, the inter-provincial population emigration and immigration levels have increased greatly with the economic development; (3) Statistically, the inter-provincial population migration is negatively correlated with the level of economic development in the emigrant place and the migration distance and positively correlated with the level of economic development in the immigrant place and the population scale in the emigrant and immigrant places; and (4) The spatio-temporal factor is an important explanatory variable of population migration. The introduction of the historical dependent variable and the spatial lag factor can improve the regression effect of the gravity model greatly, and the historical variable and the spatial factor have strong explanatory power for the inter-provincial population migration.