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Rainfall is known as the main water replenishment in dryland ecosystems, and rainfall partitioning by vegetation reshapes the spatial and temporal distribution patterns of rainwater entry into the soil. The dynamics of rainfall partitioning have been extensively studied at the inter-event scale, yet very few studies have explored its finer intra-event dynamics and the relating driving factors for shrubs. Here, we conducted a concurrent in-depth investigation of all rainfall partitioning components at inter- and intra-event scales for two typical xerophytic shrubs (Caragana korshinskii and Salix psammophila) in the Liudaogou catchment of the Loess Plateau, China. The event throughfall (TF), stemflow (SF), and interception loss (IC), and their temporal variations within the rainfall event, as well as the meteorological factors and vegetation characteristics, were systematically measured during the 2014–2015 rainy seasons. Our results showed that C. korshinskii had significantly higher SF percentage (9.2 %) and lower IC percentage (21.4 %) compared to S. psammophila (3.8 % and 29.5 %, respectively), but their TF percentages were not significantly different (69.4 % vs. 66.7 %). At the intra-event scale, TF and SF of S. psammophila were initiated (0.1 vs. 0.3 h and 0.7 vs. 0.8 h) and peaked (1.8 vs. 2.0 h and 2.1 vs. 2.2 h) more quickly, and TF of S. psammophila lasted longer (5.2 vs. 4.8 h) and delivered more intensely (4.3 vs. 3.8 mm h -1), whereas SF of C. korshinskii lasted longer (4.6 vs. 4.1 h) and delivered more intensely (753.8 vs. 471.2 mm h -1). For both shrubs, rainfall amount was the most significant factor influencing inter-event rainfall partitioning, and rainfall intensity and duration controlled the intra-event TF and SF variables. The C. korshinskii with larger branch angle, more small branches, and smaller canopy area, has an advantage over S. psammophila to produce SF more efficiently. The S. psammophila has lower canopy water storage capacity to generate and peak TF and SF earlier, and it has larger aboveground biomass and total canopy water storage of individual plants to produce higher IC compared to C. korshinskii. These findings contribute to the fine characterization of shrub-dominated ecohydrological processes, and improve the accuracy of water balance estimation in dryland ecosystems. [ABSTRACT FROM AUTHOR]

Human activities and climate change are two key factors influencing the variation of the total amount of available surface and groundwater, hereafter termed water resources. Quantitatively separating their impacts remains a challenge. To this end, we used time-varying Budyko-type equations and a hierarchical Bayesian model in this paper to separate their impacts in 31 provincial-level divisions of China. The time-varying Budyko-type equations treat the Budyko equation parameter w as a variable, which depends on human activities (represented by per capita gross regional production) and climate change (represented by temperature and precipitation). The hierarchical model quantifies the uncertainty of parameters and the interrelation between covariates across regions in China. The results show that the time-varying Budyko-type equation can improve the fitting capability for water resources in China. The hierarchical Bayesian model, which considered spatial dependence, reduced the uncertainty of the parameters compared to spatially independent counterparts. For most regions of China, human activities reduce water resources while climate change increases them. Southeastern China is the most influenced area, and its water resources decreased approximately 50 mm because of human activities. This study can provide a basis for water resource management under climate change and human activity constraints in China. [ABSTRACT FROM AUTHOR]