The key to sustainable rural development and coordinated regional development is to properly measure the livelihood resilience of rural residents (LRRR), and investigate its regional differences, distribution characteristics, and evolutionary patterns. This study combined the entropy method, the Dagum Gini coefficient and decomposition, kernel density estimation, and convergence analysis to measure the LRRR in 30 provinces of China from 2006 to 2020, and to analyze its regional differences and sources, dynamic distribution, and characteristics of convergence. The LRRR in China overall declined 2006–2020, with an east-to-west spatial gradient toward lower livelihood resilience. Intra-regional differences in LRRR narrowed in the Eastern and Central Regions, while those in the Western Region widened. Inter-regional differences were the main source of differences in LRRR. The LRRRs in most provinces in China were gradually reaching the same level over time (i.e., $\sigma$ convergence and $\beta$ convergence). This research provides a factual reference for policies related to reducing inter-provincial differences in the LRRR in China.

High-Standard Farmland Construction (HSFC) is widely expected to support both food security and low-carbon agriculture in China, yet prevailing assessments treat agricultural carbon performance (ACP) as a single aggregate, obscuring the structural asymmetry between emission mitigation and carbon sequestration. This study examines whether HSFC simultaneously reduces agricultural emissions and enhances carbon sequestration. Using a city-level panel of the Yangtze River Economic Belt (2007–2022), this study treats HSFC as a quasi-experiment and decomposes ACP into carbon sequestration performance (CSP) and carbon mitigation performance (CMP). The results show that HSFC robustly improves overall ACP and CSP, while its effect on CMP is statistically insignificant. Further decomposition indicates that HSFC promotes ACP through both efficiency change and technological change, though these gains are concentrated primarily in the sequestration dimension. Mechanism analysis shows that farmland scale management improves both efficiency and technology adoption, whereas agricultural socialized services promote both channels with a particularly pronounced effect on technological progress; neither channel, however, delivers a strong mitigation effect. In addition, the CSP-enhancing effect is robust across mechanization levels and in major grain-producing areas, whereas it is statistically absent in the upstream reaches characterized by fragmented terrain, and no significant CMP effect emerges in any subgroup. These findings provide new evidence on the climate consequences of farmland policies and offer implications for better aligning food security with agricultural decarbonization.