The portfolio model provides a new framework that enables farmers to make tradeoffs between the returns and risks of agricultural production. However, it has only been used in cost allocation among resources and in farmland allocation among crops at present. Thus, we conducted a portfolio model analysis based on an independent, mixed cross-section of data accounting for 1650 rural households in Minqin county, China, over a timescale of three years; the goal was to explore the feasibility and actuating extent of the portfolio model in optimizing the allocation of agricultural resources among crops other than farmland. The results showed that, by optimizing resource allocation among crops using a portfolio model, the return per unit resource of farmland, water, and labor increased by CNY 4.03 thousand per hectare, CNY 0.38 per cubic meter, and CNY 39.75 per day, without increasing risk, and with corresponding increases in use efficiency of 14.64%, 9.25%, and 13.55%, respectively, in the study area. Therefore, the portfolio model is a good tool for agricultural resource allocation optimization. Policy makers can manage agricultural resources according to their risk preference using this model. This study provides new insights into agricultural resource allocation and critical empirical evidence for return and risk management, as well as resource use efficiency improvement in agricultural production.

Despite extensive research on Public Service Motivation (PSM), reconciling the debate over whether PSM is a state or a trait remains a challenge among public administration scholars. Studies exploring the antecedents of PSM that engage in this debate often overlook the importance of organizational factors in influencing PSM. Framed within the literature on the behavioral aspects of performance information processing and adopting a propensity-score-matching model with data from a Chinese local government, we examine whether and how performance ratings influence public service motivation of public servants. The results show that performance ratings have a crowding-out effect, underscoring how the ways in which signals of performance feedback are conveyed to public servants can shape PSM. Our findings contribute to understanding the antecedents that preserve and promote public service motivation. We call for future research that focuses on public-value-based performance appraisal systems in centralized regimes.

Climate change and air pollution are intrinsically interconnected as carbon dioxide and air pollutants are co-emitted during fossil fuel combustion. Low-carbon policies, aimed at mitigating carbon emissions, are also anticipated to yield co-benefits for air quality; however, the extent to which regional low-carbon policies can effectively achieve significant reductions in air pollutant levels remains uncertain. In China, the implementation of the low-carbon city pilot (LCCP) policy has reduced carbon emissions, but further research is needed to examine its effectiveness regarding achieving air quality co-benefits. Adopting a difference-in-differences model with a 19-year national database of air quality, this study examines whether the LCCP policy improves air quality in China’s metropolitan areas and explores how these policy initiatives address their air pollution challenges. The results indicate that, following the implementation of the LCCP policy, the mean, maximum, and standard deviation of the AQI in pilot cities decreased significantly by 9.3%, 20.8%, and 19.8%, respectively, compared to non-pilot cities. These results suggest that the LCCP policy significantly improves air quality and provide evidence that this improvement is facilitated by advancements in green technology, industrial restructuring, and the optimization of urban planning and landscape design.