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In 2015, the Sustainable Development Goals (SDG) replaced the Millennium Development Goals (MDG), providing guidance and direction for the future development of countries around the world. Both MDG and SDG have established multiple indicators to achieve environmental sustainability. However, few studies have compared the changes in the ecological environment during the two periods. Therefore, this study selected the seven major river basins in China as the study area and comprehensively assessed the changes in ecosystem service importance (ESI) within different basins in the MDG and SDG periods based on six ecosystem services, including habitat quality, soil conservation, water yield, carbon storage, grain production, and aesthetic landscape. Specifically, the changes from 2000 to 2015 and 2015 to 2020 were used to represent MDG and SDG periods, respectively. The results showed that the overall ESI of the seven major river basins showed an increasing trend in both periods, and the proportion of extremely important basins reached 20.39% in 2020, mostly distributed in the Yangtze River basin and the Pearl River basin. Except for carbon storage, other ecosystem services were restored in the SDG period. However, COVID-19 and a series of sudden disasters in 2020 have greatly affected grain production and the aesthetic landscape. The fluctuation of habitat quality also indicated that although the ecological environment has a trend of recovery, there was still some degradation compared to 20 years ago. National protection policies and restoration projects have gradually improved the ecological environment of the seven river basins and are striving to reach the SDG standards step by step. However, many problems still need to be solved urgently, such as the reduction of ecological land, the increase in carbon emissions, and the weak resilience to disasters. China has made significant positive progress in MDG, and more efforts are needed to achieve the SDG goals in the future. [Display omitted] • The changes in ecosystem services and their importance of the seven major river basins in China were explored. • The ecosystem service importance has steadily increased in the MDG and SDG periods. • China ecological policies and restoration projects have been essential to mitigate the environment degradation. [ABSTRACT FROM AUTHOR]

The spatiotemporal changes of open-surface water bodies in the Yangtze River Basin (YRB) have profound influences on sustainable economic development, and are also closely relevant to water scarcity in China. However, long-term changes of open-surface water bodies in the YRB have remained poorly characterized. Taking advantage of the Google Earth Engine (GEE) cloud platform, this study processed 75,593 scenes of Landsat images to investigate the long-term changes of open-surface water bodies in the YRB from 1984 to 2018. In this study, we adopted the percentile-based image composite method to collect training samples and proposed a multiple index water detection rule (MIWDR) to quickly extract the open-surface water bodies. The results indicated that (1) the MIWDR is suitable for the long-term and large-scale Landsat water bodies mapping, especially in the urban regions. (2) The areas of permanent water bodies and seasonal water bodies were 29,076.70 km2 and 21,526.24 km2, accounting for 57.46% and 42.54% of the total open-surface water bodies in the YRB, respectively. (3) The permanent water bodies in the YRB increased along with the decreases in the seasonal water bodies from 1984 to 2018. In general, the total open-surface surface water bodies in the YRB experienced an increasing trend, with an obvious spatial heterogeneity. (4) The changes of open-surface water bodies were associated with the climate changes and intense human activities in the YRB, however, the influences varied among different regions and need to be further investigated in the future. [ABSTRACT FROM AUTHOR]

• Urban water bodies in China showed a significant spatial autocorrelation in spatial distribution. • About 40% and 60% of total cities were detected with a mutation point in urban permanent and seasonal water bodies, respectively. • GDP explained about 13 %∼35 % of spatiotemporal variations of urban water bodies in China. Urban water bodies constitute a vital element within the urban ecosystem. Knowledge of the spatiotemporal changes in urban water bodies and their relationship with economic development in China is critical for sustainable development. However, previous studies usually investigated the spatiotemporal changes of urban water bodies at discrete time points and ignored the relationship between urban water bodies and economic development. Here, this study first corrected freely available water body products based on spatiotemporal majority filter, thereby obtaining an improved yearly urban water body dataset. Then, the research adopted Moran's I and Anselin Local Moran's I to explore the spatial distribution patterns of urban water bodies and employed linear regression and segmented linear regression to investigate the temporal abrupt change and long-term trend of urban water bodies. Finally, we used geodetector to evaluate the relative contributions of GDP to the spatial heterogeneity of trends in urban water bodies. The study revealed a significant spatial autocorrelation in the distribution of urban water bodies, particularly notable in the "High-High" cluster within the Yangtze and Pearl River Deltas. It was observed that approximately 40 % and 60 % of total cities experienced an abrupt change in permanent and seasonal urban water bodies, respectively. Specifically, the majority of these abrupt changes occurred during 2010–2013. When considering both long-term trends and abrupt changes, permanent urban water bodies in Chinese cities exhibited primarily a steadily increasing trend, while seasonal water bodies in Chinese cities displayed two distinct temporal patterns: a steadily increasing trend and a decreasing trend followed by a subsequent increasing trend. Furthermore, it was noted that GDP exhibited a significantly positive correlation with the temporal changes of permanent urban water bodies from 2000 to 2020 at the national scale while it first showed a significantly negative correlation with the temporal changes of seasonal urban water bodies from 2000 to 2012 and then showed a significantly positive correlation from 2012 to 2020 on a national scale. In conclusion, we found that GDP played a more important role in driving the spatial heterogeneity of trends in urban water bodies during 2012–2020 compared to 2000–2012, with the relative contribution of ∼ 32.5 %. [ABSTRACT FROM AUTHOR]