Green agriculture is a new sustainable agricultural development model that coordinates agricultural development with the environment which has been vigorously promoted in China in recent years. With the support of national policies, China has set up 130 pilot zones for green agricultural development. Taking these pilot zones as quasi-natural experimental areas, the difference-in-differences (DID) method and agricultural green total factor productivity are used to evaluate the effect of the policy in the pilot zones. The findings indicate that the pilot zones notably diminish non-point source agricultural pollution without affecting agricultural added value and improve agricultural green total factor productivity by improving technical efficiency. Heterogeneity analysis shows that the effectiveness of this policy varies regionally. The eastern region of China, the main agricultural producing areas, and the regions with higher initial environmental pollution levels and abundant educational resources experience more pronounced benefits. Based on the regional characteristics of different regions, this study considers the factors such as agricultural resource endowment and development basis and explores how the policy effects of agricultural green development in different regions, which has certain guiding significance for the continuous improvement in China’s agricultural green development policies.

Aerosols and their chemical composition exert an influence on the atmospheric environment, global climate, and human health. However, obtaining the chemical composition of aerosols with high spatial and temporal resolution remains a challenging issue. In this study, using the NR-PM1 collected in the Beijing area from 2012 to 2013, we found that the annual average concentration was 41.32 μg·m⁻³, with the largest percentage of organics accounting for 49.3% of NR-PM1, followed by nitrates, sulfates, and ammonium. We then established models of aerosol chemical composition based on a machine learning algorithm. By comparing the inversion accuracies of single models—namely MLR (Multivariable Linear Regression) model, SVR (Support Vector Regression) model, RF (Random Forest) model, KNN (K-Nearest Neighbor) model, and LightGBM (Light Gradient Boosting Machine)—with that of the combined model (CM) after selecting the optimal model, we found that although the accuracy of the KNN model was the highest among the other single models, the accuracy of the CM model was higher. By employing the CM model to the spatially and temporally matched AOD (aerosol optical depth) data and meteorological data of the Beijing–Tianjin–Hebei region, the spatial distribution of the annual average concentrations of the four components was obtained. The areas with higher concentrations are mainly situated in the southwest of Beijing, and the annual average concentrations of the four components in Beijing’s southwest are 28 μg·m⁻³, 7 μg·m⁻³, 8 μg·m⁻³, and 15 μg·m⁻³ for organics, sulfates, ammonium, and nitrates, respectively. This study not only provides new methodological ideas for obtaining aerosol chemical composition concentrations based on satellite remote sensing data but also provides a data foundation and theoretical support for the formulation of atmospheric pollution prevention and control policies.