The rapid population growth around the world has become one of the main challenges for countries to ensure adequate food supply. To address this difficulty and ensure adequate food production, sustainable land use, in particular sustainable cultivated land (CL) use, can make a great contribution. Sustainable utilization of CL encompasses several aspects such as quantity and quality, but previous studies have focused on increasing food production, while the interrelationships among cultivated land quantity, quality, and grain yield (CLQQGY) have still received less attention. Hence, based on the GlobeLand30 data during 2000–2020, this paper analyzed the changes of CLQQGY in 130 prefecture-level cities in the Yangtze River Economic Belt (YREB) in China and explored whether the current consecutive harvests is sustainable in the future to feed increasing population. The results revealed the areal loss and quality degradation of CL in most cities in the YREB, the total CL area decreased by 31.07 × 104 hm2 and 282.59 × 104 hm2 during 2000–2010 and 2010–2020, respectively, and the CL quality declining trend was presented in 68.46% and 69.23% cities in the YREB during 2000–2010 and 2010–2020, respectively. Even with such acreage and ecological losses, the total grain yield still increased by 3.77% and 9.53% during 2000–2010 and 2010–2020, respectively, continuing the miracle “continuous harvests” of grain yield in this region. This successive increase in food production in the context of decreasing acreage and ecological deterioration of CL depend mainly on the amount of chemical fertilizer usage, the total power of agricultural machinery and rural electricity consumption. However, due to the heavy reliance on a growth model driven by resource inputs, this type of harvest appeared to be unsustainable because of the significant negative effects brought out by overusing resources. With a view to achieving sustainable use of CL and food production, therefore, this paper proposed policies to promote the sustainable use of CL and food supply for supporting the survival of increasing population through the full implementation of administrative regulations and economic measures that focus on the balance among the quantity and quality and food production of CL in the process of agricultural production and CL management.

Under the dual pressures of increasing fragmentation of farmland and profound changes in the agricultural labor force, the problem of abandoned farmland in rural China has become increasingly prominent, posing a serious threat to food security. Previous studies have mainly focused on the impact of socioeconomic factors on farmland abandonment behavior; however, there remains a lack of systematic investigations into the underlying mechanisms through which farmland fragmentation influences farmers’ land-use decisions. Therefore, this study applies behavioral theory to construct a “fragmentation–mechanization–abandonment” analytical framework to analyze the potential mechanisms of land-use decision-making. Using micro-level household survey data from multiple provinces across China, we conduct empirical tests through Probit models and Karlson Holm and Breen (KHB) mediation effect analysis. Our findings include: (1) Farmland fragmentation significantly increases the probability of farmland abandonment, which remains robust across multiple tests. (2) Farmland fragmentation indirectly influences abandonment behavior through the mediating variable of agricultural mechanization level, but this mechanism plays only a partial mediating role. (3) Heterogeneity tests indicate that the positive effect of farmland fragmentation is significantly stronger among households with low access to finance than among those with high access to finance. This influence is also stronger among households with high farmland accessibility. This study indicates that abandonment governance requires moving beyond a singular focus on land consolidation and shifting toward a synergistic approach that combines differentiated regional strategies with targeted support for smallholders. From a micro-mechanism perspective, this study provides empirical evidence for targeted implementation of land consolidation and livelihood support for smallholders, offering important policy implications for achieving agricultural modernization.

Carbon Emission Trading Policy (CETP) has proven effective in reducing emissions and addressing climate challenges globally. Beyond environmental benefits, CETP also holds significant potential for enhancing societal well-being, improving quality of life and fostering residents’ happiness. Employing entropy-weighted indices guided by Sustainable Development Goals (SDGs), this study analyses the impact of CETP on green welfare performance across 31 provincial panel data during 2000–2023 in China through a comprehensive evaluation framework. By adopting the difference-in-differences (DID) approach, this research assesses the effects of CETP on green welfare while conducting mechanism tests focused on scientific and technological innovation and employment structure optimization, and heterogeneity analysis is also performed to explore regional disparities. The results are as follows: (1) CETP significantly increases residents’ green welfare in pilot regions, and this is robustly confirmed through propensity score matching with difference-in-differences (PSM-DID) and placebo tests. (2) The policy enhances residents’ green welfare primarily through advancements in technological innovation and the optimization of employment structures. (3) Regional heterogeneity analysis indicates that CETP generates greater improvements in residents’ green welfare in central regions than in eastern and western regions. Based on the above results, this study proposes the orderly implementation of CETP and the promotion of technological innovations for carbon reduction and industrial upgrading. This study provides policy-makers with appropriate policy formulation recommendations to balance economic growth and green welfare.

Pollution control and carbon mitigation often involve the same energy inputs and production processes, yet the role of finance in shaping their combined urban outcomes remains insufficiently understood. Using panel data for 110 Chinese cities in the Yangtze River Economic Belt (YREB) from 2010 to 2023, this study examines the relationship between green finance (GF) and joint pollution and carbon reduction performance (JPCRP), while JPCRP is measured using an outcome-based composite index covering carbon emissions, energy use, and conventional pollution. The empirical analysis combines city and year fixed effects with two stage least squares, indirect path, interaction, and panel threshold models. The results show that GF is positively associated with JPCRP, while exploratory subgroup estimates vary in magnitude across basin locations and development levels. Specifically, the fiscal expenditure analysis identifies a countervailing pathway in which GF is positively associated with fiscal environmental expenditure (FEE), while FEE is negatively associated with JPCRP after controlling for GF and the other covariates. Green technological innovation (GTI) conditions the relationship between GF and JPCRP, with the negative GF × GTI interaction indicating that the marginal association between GF and JPCRP becomes weaker as GTI increases. The estimated threshold for urban spatial development efficiency (USDE) is 0.66, above which the GF coefficient remains positive but declines from 0.1412 to 0.0845. These findings indicate that the environmental contribution of GF depends not only on the supply of green capital but also on fiscal allocation, technological capacity, and urban spatial conditions.