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Riverine wetland is one of the important cityscapes along rivers, featuring powerful eco-hydrological regulations in safeguarding urban security and serving its quality. Over the past several decades, intensified climate change, together with the upgraded human activities, have deeply disturbed riverine wetland worldwide and caused variations in the amount and pattern, which might lead to negative effects on wetland ecosystem health (WEH), thus threaten the sustainability of the riverine urban agglomerations. To better understand the mechanism of the above effectiveness, the Riverine Urban Agglomerations along the Yellow River in China’s Ningxia Hui Autonomous Region (RUAN) was taken as an example in the present study. First, by establishing an object-oriented remote sensing image classification system based on Classification and Regression Tree (CART), riverine wetland distribution in years of 2000, 2009 and 2018 were determined for a two-Stage (ST-I: 2000–2009, ST-II: 2009–2018) comparative research. Second, the transition matrix and landscape index were used to measure the spatiotemporal dynamics of the riverine wetland in the two stages. Third, a Pressure-State-Response (P-S-R) model, together with its index system, was constructed to comprehensively assess the WEH in there. Results revealed that: (1) Wetlands in RUAN are dominated by the artificial ones, presenting an overall increase in area during the statistical period, varying with different trends in the two stages. Conversion between the wetlands and the non-wetlands were found frequent during the urbanization, leading to remarkable changes in wetland patterns in space. (2) Rivers are important and basic in forming riverine landscape in RUAN, the natural wetlands increased during the statistical period. In general, wetland patches and diversity increased, shapes of that became homogenized. Accordingly, the aggregation of wetlands decreased and the fragmentation of that worsened. (3) Riverine wetlands in most of RUAN experienced an increase of external pressure and a deterioration of state, showing an overall degradation. Meanwhile, the WEH was determined more by the fundamental state of itself, the external disturbance seemed function less. Above findings confirmed the vulnerability of riverine wetlands during urbanization in an arid circumstance. It is worthy of strengthening the protection of existing wetlands and minimizing or eliminating the conversion, to ensure the WEH and serve the sustainability of riverine urban agglomerations.

Study region: Southern Gansu Plateau (SGP), located in the northeastern region of the Qinghai-Tibet Plateau, is a representative alpine-cold water source area for China’s large rivers, such as the Yellow River and Yangtze River. Study focus: Identifying the contributions of dominant factors to the regional soil erosion rate (A) is important for understanding the environmental processes and benefits of water and soil conservation, although related studies have seldom been conducted in alpine-cold regions such as the SGP. Accordingly, the main objectives of this study are (1) to determine the spatiotemporal dynamics of soil erosion and its driving factors in the SGP area; (2) to quantify the relationship between the main influential factors and soil erosion; and (3) to separate the contributions of the above factors to variations in regional soil erosion on the SGP. New hydrological insights for the region: The multiyear average regional A for the SGP region was calculated as 24.18 t·hm−2·a−1, corresponding to an overall low intensity of regional soil erosion. The contributions of various time-varying factors, such as rainfall, vegetation cover, and conservation practices, to the reduction in A were −20.01%, 81.07%, and 21.95%, respectively, indicating that the improvement in land surface vegetation ecology dominated the decrease in A under the background of climate warming. The findings are expected to contribute to soil and water conservation in alpine-cold river source regions.

Clarifying the relationships among regional ecosystem service values is important for ecosystem service management. However, most current studies are based on historical periods or individual time points, and there is still a lack of research on the scenario analysis of the relationship of ecosystem service values. We chose the Yinchuan Plain in northwest China as the research object. Firstly, three development scenarios of natural development, ecological protection, and economic priority were designed. Based on the CA-Markov model, a multi-scenario simulation of land use in the Yinchuan Plain is carried out. The value equivalence factor method was then used to calculate the value of ecosystem services, and the Pearson correlation coefficient method was used to analyze the trade-offs and synergistic relationships between the values of different ecosystem services. Finally, K-Mean cluster analysis and stable metaphorical change trajectory method were used to identify ecosystem service bundle and their evolution trajectories. We found that the ecosystem service value of Yinchuan Plain shows an upward trend under the ecological protection scenario, and the rest of the scenarios and historical periods show a downward trend to varying degrees, and the ecosystem service value declines the most under the economic priority scenario. The dominant cluster is based on food production, and this service bundle is the main function throughout the year. Combining different landscape types, we synthesized the trade-offs and synergies between ecosystem service bundles and various ecosystem services values in different scenarios to formulate management strategies for future ecosystem services in different landscape partitions.