Spatiotemporal variation and prediction of NPP in Beijing-Tianjin- Hebei region by coupling PLUS and CASA models

Abstract

Context Vegetation productivity is crucial for human production and livelihoods. Monitoring changes in NPP (Net Primary Productivity) is essential to evaluate regional ecological shifts and carbon sink capacity. Objectives Our objective is to explore the variations of NPP during 2001–2020 and propose a new idea to predict the actual NPP in 2030 under multiple climate scenarios, taking the Beijing-Tianjin-Hebei (BTH) region as an example. Methods This study utilized the PLUS (patch-generating land use simulation) and improved CASA (Carnegie-Ames-Stanford Approach) models, along with remote sensing and climate data, to estimate changes in NPP in the BTH region for the period 2001–2020 and predict NPP in 2030. Results The results indicate that, during the period of 2001–2020, the NPP in the research area maintained a spatial distribution pattern, with higher values in the northeastern forest area, a slightly higher value is found in the southeast of the city, while a lower value is found in the northwest and center, showing an overall gradual improvement trend. However, the NPP in the study area is predicted to decline in 2030 compared to 2020, albeit better than that in 2001–2015. Moreover, NPP will decline in 2030 under three future climate scenarios, and the NPP condition is optimal under the SSP 1-2.6 scenario. Conclusions NPP will decline in 2030 in the BTH region, it may be related to some current ecological policies. Comparing NPP development under three future climate scenarios, we find that a low-emission scenario, which represents a green development model, is more favorable for the development of NPP. This research sheds light on the variations of NPP in the BTH region and offers a scientific basis for relevant departments to formulate future policies.