Tao Lin

Water yield (WY) is a key indicator of water availability and the mechanisms regulating WY have become increasingly complex with ongoing global changes in climate and vegetation. Existing studies remain confined to the relative contribution and interacting pathways of multiple drivers, providing limited insights into heterogeneity across different regions. This study conducted a global spatiotemporal analysis of WY using multi‐source remote sensing and meteorological data from 1982 to 2020, integrating the Random Forest model and Structural Equation Model to quantify the relative contributions and pathways of climate and vegetation changes to WY at global and regional scales (arid and humid regions). The results show: (a) WY increased at the global scale and in arid regions but decreased in humid regions; (b) Climate change contributed more to WY at the global scale (relative contribution ratio, R = 55.11%) and in humid regions ( R = 62.00%), whereas vegetation change contributed relatively more in arid regions ( R = 64.49%); (c) Globally, the Palmer Drought Severity Index (PDSI), vapor pressure deficit, and wind speed exerted positive effects on WY. Downward surface shortwave radiation and Leaf Area Index (LAI) had negative effects. Notably, the positive effect of PDSI weakened in arid regions but strengthened in humid regions, whereas the negative effect of LAI reversed. These findings highlight the nonlinear and regional responses of WY and provide a scientific basis for ecological restoration and water resource management.

Due to climate change and urbanization, green roofs are vital for urban climate resilience. However, there is currently no consensus on the photosynthetic carbon uptake capacity of green roof plants in cities. This study investigated and compared nine common green roof plant species in Xiamen, a typical coastal city in southeastern China. Their photosynthetic parameters were measured across all four seasons to evaluate photosynthetic carbon uptake capacity, and the differences among the nine plant species were evaluated. Results show: (1) Significant interspecific differences exist. Ligustrum japonicum (Lj) had the highest seasonal average daily carbon uptake per unit leaf area (8.86 g m⁻² d⁻¹) and per unit area (93.10 g m⁻² d⁻¹), approximately 9 times that of the lowest-performing species per unit leaf area (Pedilanthus tithymaloides) and 11 times that of the lowest-performing species per unit area (Tradescantia spathacea). (2) The variation in carbon uptake capacity among different green roof plant species followed a pattern consistent with that of their net photosynthetic rate and leaf area index. (3) Overall, the carbon uptake capacity of the nine plant species exhibited a trend of trees > shrubs > herbs. In summary, Lj demonstrated the highest photosynthetic carbon uptake capacity among the nine species examined, suggesting its potential as a promising species for enhancing photosynthetic carbon uptake on green roofs in southeastern coastal cities.

Regulatory effects of liquid water path (LWP) on cloud droplet effective radius (CER) and the interaction between aerosol optical depth (AOD) and cloud properties were systematically investigated. MODIS and CALIOP observed aerosols and clouds over eastern China in two periods: 2008–2014 (period 1) and 2015–2022 (period 2). The results show two distinct regimes of the variation of CER with LWP: a rapid growth regime (LWP < 55/50 g/m²) and a decreasing regime (LWP = 55–135/50–100 g/m²) (thresholds vary by period). The sensitivity of CER to AOD (S_CER) shows a negative correlation, and the S_CER in the LWP regime 2 shows larger than that in LWP regime 1. Here, the spatial scale is described by buffer size and study area. Overall, |S_CER| decreases with increasing spatial scale. The optimal buffer sizes show notable variations in the range from 6°×6° to 10°×10°: increasing as study areas increase in period 2, but decreasing in period 1 for LWP regime 2. Compared with period 1, |S_CER| in period 2 exhibits significantly decreases, reflecting the weaker of aerosol-cloud interactions for declining aerosol concentrations. Additionally, the sensitivity of N_d (cloud droplet number concentration) to AOD (S_Nd) shows a positive correlation, with S_Nd decreases as spatial scale increases. The optimal buffer sizes show larger in the 8°×8° and 10°×10° regions than that in the 4°×4° and 6°×6° areas. This study reveals the scale-dependence of aerosol-cloud interactions.

Regulatory effects of liquid water path (LWP) on cloud droplet effective radius (CER) and the interaction between aerosol optical depth (AOD) and cloud properties were systematically investigated. MODIS and CALIOP observed aerosols and clouds over eastern China in two periods: 2008–2014 (period 1) and 2015–2022 (period 2). The results show two distinct regimes of the variation of CER with LWP: a rapid growth regime (LWP < 55/50 g/m²) and a decreasing regime (LWP = 55–135/50–100 g/m²) (thresholds vary by period). The sensitivity of CER to AOD (S_CER) shows a negative correlation, and the S_CER in the LWP regime 2 shows larger than that in LWP regime 1. Here, the spatial scale is described by buffer size and study area. Overall, |S_CER| decreases with increasing spatial scale. The optimal buffer sizes show notable variations in the range from 6°×6° to 10°×10°: increasing as study areas increase in period 2, but decreasing in period 1 for LWP regime 2. Compared with period 1, |S_CER| in period 2 exhibits significantly decreases, reflecting the weaker of aerosol-cloud interactions for declining aerosol concentrations. Additionally, the sensitivity of N_d (cloud droplet number concentration) to AOD (S_Nd) shows a positive correlation, with S_Nd decreases as spatial scale increases. The optimal buffer sizes show larger in the 8°×8° and 10°×10° regions than that in the 4°×4° and 6°×6° areas. This study reveals the scale-dependence of aerosol-cloud interactions.