Abstract: Promoting sustainable income growth of lowincome groups is the economic foundation for rural revitalization The “complete victory” in poverty alleviation shows that fiscal funds have played a huge role in ensuring income growth for lowincome groups However， the targeted fiscal funds， such as special poverty alleviation funds from the central government， is temporary， and will change with the economic and social development of different regions The income growth heterogeneity after the reduction in financial support provides new evidence for sustainable development of lowincome groups
This study uses synthetic control method to evaluate the regional heterogeneity of rural income growth after the reduction of financial support based on countylevel panel dataset from 2006 to 2019， and further explores the reason of this regional heterogeneity The main findings of this study are as follows： First， the observed 31 counties can be divides into three types according to income growth of lowincome groups， including the rising type （about 3548%）， the declining type （about 4516%）， and the invariant type （about 1936%） Second， the reduction in financial support increases fiscal expenditure pressure of local governments Underdeveloped areas rely heavily on financial support from higherlevel governments， and local governments still have significant expenditure demands for linking up rural revitalization Third， the decreased fiscal income and increased expenditure pressure lead to an overall reduction in fiscal expenditure， which has heterogeneous effects on different types of regions On the one hand， it results in suppressing effects， where regions with relatively strong selfdevelopment capabilities still show an accelerating growth trend， albeit at a reduced rate On the other hand， it leads to restraining effects， where regions with relatively weak selfdevelopment capabilities show slowed income growth Fourth， Continuous optimization of industrial structure and infrastructure construction plays a positive role in improving selfdevelopment capabilities However， the positive effect of financial loans has not been fully released due to financial power exclusion， and low financial capacity， etc
Based on the above findings， this study proposes the following policy recommendations： First， we should tailor and implement support， guarantee， and incentive policies according to local conditions Second， we should make full use of incentive and constraint mechanisms to encourage local governments to strengthen their own financial resources construction， such as linking financial support with the growth of the local governments own financial capacity Third， we should leverage the positive role of fiscal funds in promoting the inflow of production factors into underdeveloped areas， such as highskilled labors， market capitals， hightech technologies， etc， to fundamentally enhance the selfdevelopment capabilities of the underdeveloped areas and lowincome groups

Key words: rural revitalization, income growth of the low-income groups, reginal heterogeneity, financial support, synthetic control method

摘要： 促进欠发达地区农民持续增收是实现乡村全面振兴的经济基础。本文基于2006—2019年县级面板数据，以脱贫县农民为研究对象，使用合成控制法评估财政资金支持力度下降后欠发达地区低收入群体的收入增长情况及地区异质性。研究发现：与合成县相比，约3548%的县的农民收入增长幅度上升，约4516%的县下降，约1936%的县基本无差异。财政收入端和支出端的共同挤压使得地方政府财政支出压力增大，进一步对地方政府整体财政支出产生约束，进而对不同自我发展能力的地区产生异质性影响。进一步分析表明，产业结构优化与基础设施建设提升了欠发达地区的自我发展能力，为低收入群体持续增收提供了原动力。

关键词: 乡村振兴, 低收入群体增收, 地区异质性, 财政资金, 合成控制法