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Vegetation changes have a significant impact on the runoff and sediment process of rivers in arid areas. Since 2000, the middle reaches of the Yellow River Basin have experienced rapid vegetation restoration, and the sediment transport in this area has also shown a significant decreasing trend. In this paper, we selected 10 rivers from north to south located in the middle reaches of the Yellow River as the research area, and analyzed the temporal and spatial characteristics of vegetation restoration and changes in runoff and sediment, as well as the effects of vegetation restoration on runoff and sediment process. The results show that sediment transport modulus in the middle reaches of the Yellow River are very significantly decreasing (p < 0.001), and the rate of change of the northern rivers is higher than that of the southern rivers. During the periods of 1956–1979 and 1980–1999, the sediment transport modulus showed a very significant decreasing trend from north to south (p < 0.001), but the trend of significantly decreasing the sediment transport modulus from north to south from 2000 to 2020 no longer existed (p = 0.761), after 2000, the middle reaches of the Yellow River underwent a rapid process of vegetation restoration, vegetation restoration significantly reduced the spatial heterogeneity of river sediment transport. Partial correlation analysis and sensitivity analysis show that, there was no significant correlation between vegetation restoration and runoff reduction (R2 = 0.03, p = 0.63), but there was a significant correlation between vegetation restoration and reduced sediment transport modulus (R2 = 0.49, p < 0.05), and a significant correlation between vegetation restoration and decreased sediment concentration (R2 = 0.66, p < 0.01). During the periods of 1981–1999 and 2000 - 2020, the relationship between precipitation and sediment transport modulus was positively correlated. In the 1981–1999 period, NDVI showed a weak negative correlation with sediment transport modulus but in the 2000 - 2020 period, NDVI and sediment transport modulus showed a significant negative correlation. This study provides valuable insights into the natural response of river sediment transport to vegetation restoration, and the findings are critical for soil and water conservation planning in arid area. [ABSTRACT FROM AUTHOR]

To maintain the coordinated development between human and natural ecosystem, it is essential to understand the spatial heterogeneity of urbanization impacts on ecosystem services (ESs). The Yellow River Basin (YRB) in China, with a fragile ecological environment, is experiencing large-scale and rapid urbanization. To fill the research gap and meet current needs, we estimated the comprehensive urbanization level (CUL) from four aspects in the YRB and the five key ESs using material value methods. Then, we examined the correlations between ESs and CUL by Pearson correlation analysis, and explored the spatial heterogeneity of urbanization impacts on ESs by geographically weighted regression. The results indicated that: (1) CUL increased remarkably from 0.2283 in 2000 to 0.3722 in 2015, with the subindexes ranking of DUL (demographic) > SUL (social) > EUL (economic) > LUL (landscape); (2) grain production (GP), carbon sequestration and oxygen production (CSOP), and water yield (WY) increased, whereas soil retention (SR) and habitat quality (HQ) decreased. The five ESs exhibited an overall pattern of low values in the northwest and high values in the southeast; (3) on the whole, CUL had positive and significant relationships with GP (0.4150), CSOP (0.1635), and WY (0.2475). The impacts of ULs on ESs had significant spatial heterogeneity. CUL has strong positive impacts on GP, CSOP, and WY in the central regions but negative ones on the northwestern and eastern regions. Specific recommendations are proposed for optimizing human activities and protecting the ecological environment. [Display omitted] • Comprehensive urbanization level was estimated in this paper for YRB region. • The analysis considered demography, landscape, economy and society. • Five typical types of ecosystem services were estimated during 2000–2015. • Pearson correlations between urbanization and ecosystem services were investigated. • Spatial heterogeneity of urbanization impacts on ecosystem services was analyzed. [ABSTRACT FROM AUTHOR]