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[Objective] The response characteristics of vegetation NDVI to population density change were explored to reveal the migration track of vegetation NDVI and population density center of gravity in the Bohai Rim region, in order to provide a theoretical basis for vegetation monitoring and management and ecological environment protection in the region. [Methods] Based on the MOD13A3 NDVI and population density time series from 2000 to 2020, the methods of Theil-Sen Median analysis, Mann-Kendall significance test, Granger causality test, Getis-Ord Gi* analysis, and center of gravity transfer model were used to study the spatio-temporal variation of vegetation cover and the hotspot variation of population density. [Results] ① from 2000 to 2020, NDVI in the Bohai Rim region showed an upward trend, with an upward slope of 0.022/10 a, and the area of NDVI rising was much larger than that of falling area. The rising rate of NDVI from 2000 to 2010 was significantly higher than that from 2010 to 2020. ② From 2000 to 2020, the proportion of hot spots and cold spots in the change of population density in the Bohai Rim region was 11.26% and 46.84% respectively. The change of population density was mainly in the cold spot region, which mainly extended in strips from the northeast of the Bohai Rim region to the northwest and some areas in the southeast of Shandong Province. ③ There was a one-way Granger cause of population density on NDVI around the Bohai Sea. The change of population density was the Granger cause of the change of NDVI, while the change of NDVI was not the Granger cause of the change of population density. On the whole, the growth of population density mainly had a negative effect on regional NDVI. The higher the degree of population agglomeration, the more significant the decline of NDVI. ④ There was no obvious spatial pattern in the migration direction of NDVI center of gravity of vegetation from 2000 to 2020, but it generally migrated to the northwest, and the center of gravity of population density migrated from the southeast to the northwest. [Conclusion] From 2000 to 2020, the NDVI in the Bohai Rim region shows an upward trend. The increase of population density has a negative impact on the change of NDVI. Further study needs to be conducted considering the impact of population density change and climate change on NDVI change in the Bohai Rim region.

[Objective] The temporal and spatial evolution characteristics of net primary productivity (NPP) of the terrestrial vegetation ecosystem in the Yangtze River basin were studied to provide a reference for government departments to establish and adjust ecological function restoration projects. [Methods] The Zhou Guangsheng-Zhang Xinshi model (ZGS) and the Thornthwaite Memorial model were used to estimate NPP in the Yangtze River basin based on precipitation and temperature data from 2000 to 2019. Furthermore, Pearson correlation coefficient, linear regression analysis, and the Mann-Kendall trend test were applied to analyze the spatiotemporal variation of vegetation NPP of terrestrial ecosystems in the Yangtze River basin. [Results] ① The spatial and temporal variation of NPP derived from the above two models were basically homogeneous in the Yangtze River basin. Actual NPP and potential NPP were positively correlated (0.982). ② Both actual NPP and potential NPP in the Yangtze River basin increased over time at a rate of 6.85 g/(m2·yr) and 2.74 g/(m2·yr), respectively, from 2000 to 2019. ③ Actual NPP and potential NPP were higher in the southeast and lower in the northwest portions of the Yangtze River basin. The low values were mainly distributed in grassland ecosystems, and the high values were mostly distributed in forest ecosystems and farmland ecosystems. ④ The areas with increasing trends for actual NPP accounted for 80.64% of the total area, and 84.79% of the total area for potential NPP in the Yangtze River basin, mainly distributed in Yunnan, Qinghai, Tibet, the north of Sichuan, and most regions of Zhejiang and Shanghai. The areas with decreasing trends actual NPP accounted for 19.36% of the total area and 15.19% of the total area for potential NPP in the Yangtze River basin, mainly distributed in He'nan and Hubei Province. [Conclusion] The NPP of vegetation ecosystems in the Yangtze River basin has increased in the past 20 years, indicating that natural resource management and environmental protection policy implementation in the Yangtze River basin has produced remarkable positive effects on regional ecosystem protection and development.

Starting with the view o f institution change, the cause, connotation and significance of assessment system for physical literacy was explored from the perspectives of its origin, construction and system practice, taking the reform of school physical education practice in Shanghai as the case study. It reveals that it is the development strategy o f the Party and government, as well as the practice of the reform in Shanghai, that renews the connotation and cognition value of school physical education, which forms the basic root for the institution change of assessment system.The assessment system, including theory model and detailed management system, bases its change on the principles of science, reason and effectiveness.Its practical application is the institution practice, whose value lies in its dispersible, balanced and demonstrative effect brought about by the institution change in core areas. [ABSTRACT FROM AUTHOR]