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• Framework to quantify collective and individual impacts of climate change and human activities on hydrological regimes. • Climate change and human activities have opposite effects on minimum flow and pulse indicators in the Ganjiang River bBasin. • Climate change and human activities exhibit a substantial synergistic effect on multiple aspects of hydrological regimes. Previous research rarely identified the synergistic effects of climate change and human activities on hydrological regimes, thus leading to an incomplete attribution of hydrological regime changes. To address this issue, this paper presents a complete approach for accurately quantifying these impacts. The framework integrates various methodologies, including the runoff abrupt change point judgment method for distinguishing pre- and post-impact periods, The Soil and Water Assessment Tool (SWAT) is used to isolate runoff processes influenced solely by climate change, the linear separation method for identifying runoff processes affected solely by human activities, and the Indicator of Hydrologic Alteration (IHA) for quantifying changes in hydrological regimes. Application of this framework to the Ganjiang River Basin (GRB) unveils significant alterations in hydrological regimes. This has resulted in a significant decline in aquatic organism species compared to the prior-impact period levels. Notably, climate change and human activities exert opposing effects on minimum flow indicators and flow pulse indicators in the GRB. Moreover, these factors exhibit a substantial synergistic effect on numerous indicators, resulting in hydrological regimes combined influenced by climate change and human activities being considerably different with the cumulative impact on hydrological regimes solely influenced by climate change and those solely influenced by human activities. Consequently, in future water management, it is crucial to recognize the positive role of prudent human activities in mitigating the adverse impacts of climate change. [ABSTRACT FROM AUTHOR]

• The impact of precipitation, slope, and swamp wetland ratio on water yield is not affected by spatial scale and watershed. • Identifying key areas for ecosystem services combined with multiple scenarios can help to take ecological restoration. • The water yield in the Baihe basin is more sensitive on climate change, while the water yield in the Heihe basin is more easily affected by land use changes. • The economic development and ecosystem services can both be ensured by wetland ecological restoration. Water supply is one of the core ecosystem services functions for wetland. Due to the important status of Zoige wetland, assessment of water supply in Zoige wetland is significant for ecological security all over the world. In this paper, Heihe and Baihe basins in Zoige wetland were taken as research objects, the water yield module of the Integrated Valuation of Ecosystem Services and Trade-offs (InVEST) model was used to spatially quantify water supply, with the aims of revealing the driving mechanism of water supply under different basins and spatial scale. We observed the spatial pattern change of water yield under baseline and eleven future scenarios and used the ANOVA of repeated measures and multiple linear regression model to explore the patterns and driving factors of water supply in Heihe and Baihe rivers basins. The research results were as follow. (1) The precipitation is main factor to improve water yield, but this intensity is different in different basins and spatial scale. Topography, climate, vegetation, and percentage of wetland conditions have important impacts on water yield services. However, the impacts of these conditions on water yield were various significantly across different watersheds and spatial scales (excluding factors such as precipitation, slope, and percentage of swamp wetland). (2) The spatial pattern of water yield main was affected by land use change and the amount of water yield main was affected by future climate change. (3) Water yield in the Baihe basin was more sensitive to climate change, while the Heihe basin is more sensitive to land use changes. Wetland ecological restoration strategies can effectively improve regional water yield, especially in the Heihe basin. (4) In all scenarios, the southeast regions of the study region were both the main hot spots of water yield. Wetland ecological restoration strategies have added hot spots in the north regions of the Baihe river basin, reduced hot spots in the middle-south regions of the Heihe basin. [ABSTRACT FROM AUTHOR]

[Display omitted] • We develop a framework to estimate future Flood Regulation Service (FRS) dynamics. • The framework considers the joint impacts of both climate change and urbanization. • Future FRS supply–demand imbalance will continue to intensify. • Future impacts of climate change in Baiyangdian Lake Basin cannot be ignored. • Cities should actively adapt to climate change to reduce flood risks in the future. Estimating the supply–demand relationship's future dynamics and trend of Flood Regulation Service (FRS) is important for preventing flood risks and choose an appropriate future development path. Less attention has been given to assessing the future trends in this relationship under the joint influence of climate change and urbanization. This paper aims to quantify future trends in the FRS supply–demand relationship under the joint impacts of climate change and urbanization. To this end, we took the Baiyangdian Lake Basin as an example and developed a "Climate Change-Urbanization-FRS supply and demand" framework by combining future climate scenarios from the ScenarioMIP (Scenario Model Intercomparison Project) dataset and socioeconomic data from the SSPs (Shared Socioeconomic Pathways) to estimate the FRS supply and demand dynamics during the period from 2020 to 2050. The results show that the framework has a reasonable ability to estimate the FRS supply–demand relationship. The correlation coefficients between estimated supply–demand ratios and the historical values exceeded 0.9. The average FRS supply–demand ratio among the four scenarios shows a significantly downward trend between 2020 and 2050. The FRS is expected to decrease by 0.159 (36.6 %), resulting in the imbalanced area increasing from 38.3 km2 (4.1 % of the whole basin) to 11049.7 km2 (36.2 %). We believe that although urbanization is the dominant factor contributing to the intensified imbalance trend (with a contribution of 71.2 %), influences from climate change also cannot be ignored (with a contribution of 28.8 %). Therefore, adaptation actions to climate change should be actively taken to reduce urban flood risks in the future. [ABSTRACT FROM AUTHOR]