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The Yangtze River Basin has periodically been subject to torrential rains and floods. It is of great significance to characterize the extreme precipitation patterns to learn about frequent flood characteristics in the Yangtze River Basin. Commonly, spatiotemporal characteristics of extreme precipitation was studied by regional frequency analysis method with site data. Spatial sparse site data may cause imprecise divisions of homogeneous regions. In this paper, the spatiotemporal characteristics of extreme precipitation was studied by regional frequency analysis with corrected satellite‐based grid precipitation data (Global Land Data Assimilation System, GLDAS) rather than site data. The results show that: (1) The corrected GLDAS daily precipitation data had greatly improved its ability to capture extreme precipitation events in Yangtze River Basin, as the data average accuracy increased from 0.215 before correction to 0.849 after correction. It is feasible to use satellite‐based grid precipitation data to replace the site data for the regional frequency analysis of extreme precipitation. (2) The Yangtze River Basin was categorized into seven homogeneous regions for the annual maximum 1‐day (RX1DAY) index with an automatic subjective adjustment method. (3) The regional growth curves and quantiles of the Yangtze River Basin were drawn for the return period for 2–100 years. (4) Spatial patterns of extreme daily precipitation series with a return period of 100 years indicated that the precipitation amount increases gradually from the upper to the lower Yangtze River Basin, from the "arid zone" to the "wet zone" and then to the "special wet zone", and the 100‐year return level of RX1DAY varied from 30.3 to 301.8 mm. There were three main precipitation centres, the Sichuan Basin, Dongting Lake Basin, and a great triangle area covering the Poyang Lake Basin and the south foot of Dabie Mountain. [ABSTRACT FROM AUTHOR]

Quantification of the relationship between agricultural water use and social development is important for the balance between conserving water resources and sustainable economic development. The agricultural water footprint (AWF) from crop production across 11 provinces in the Yangtze River Basin (YRB) of China, from 1999 to 2018, was calculated in the current paper. The driving factors which affected the provincial AWF were revealed using the logarithmic mean Divisia index (LMDI) model, based on a temporal and spatial variation assessment. The results showed that, with a growth rate of 1.95% per year, the annual AWF of the in the basin was 441.6 Gm3 (green water accounted for 73.63% of this) in the observed two decades. The Jiangsu, Anhui, Hubei and Sichuan provinces jointly accounted for 54% of the total AWF of the region. Cereal, cotton and fruit crops contributed most of the AWF, and determined the trends of the AWF over time. With the development of the economy and market demand, the dominant crop contributing to the AWF has shifted, from cereal and cotton around 2000, to cereals and fruits at present. The economic level was the main contributing factor driving the AWF. However, water use intensity was the most important factor which inhibited the growth of the AWF. Irrigation technology and the degree of urbanization also played a certain inhibitory role. There were significant differences in the driving effects among the different provinces. A comprehensive evaluation of the AWF and analysis of its driving factors provides a solid foundation for optimizing planting structure, strengthening water resource management, and enhancing regional exchanges and cooperation. [ABSTRACT FROM AUTHOR]

Coupled human and natural system research is an urgent issue in the Anthropocene. However, this has not yet been conducted from the perspective of multiplex networks, which are a powerful tool to elucidate the interactions in human-natural systems. This paper establishes a framework of human-water multiplex networks (HWMNs) to explain the combined effects of human-water interactions in the Yangtze River basin. The spatial linkages and the status of each province in the Yangtze River basin can be characterized through the index of network flow and topology. Research demonstrated that the highest import flow of the virtual water environment capacity flow in the Yangtze River Basin is to Jiangsu Province, at 16.2 thousand t. The highest export flow in the Yangtze River Basin is from Shanghai city, at 33.2 thousand t. The control power of Shanghai city over Sichuan Province accounts for 56.59% of the water resources, which is the highest value and can be recognized as one type of telecoupling of water resources. The provinces in the delta of the Yangtze River basin, including Shanghai city, Jiangsu Province and Zhejiang Province, benefit the most from economic trade. The community structure of the virtual water environment capacity flow is highly consistent with the geographical distribution of the Yangtze River basin. Comprehensive research methods combined with network flow analysis and network topology analysis provide more general results. The microenvironmental effect of indirect pollutant discharge is uncovered through HWMNs. This research can provide a more connected view of integrated water management. Image 1 • A framework of HWMN is established to reveal the combined environmental effects. • The key provinces are revealed through the network flow analysis and topology analysis. • The provinces in the Yangtze river delta obtains most of the water environment benefits. • The environmental effect of the indirect pollutant discharge through HWMN is revealed. [ABSTRACT FROM AUTHOR]