Lakes are important surface water bodies, and ongoing climate change is a growing threat to the hydrological cycle and water resource availability of lakes in arid regions. Accurately estimating different drivers’ contributions to lake water volume can enhance our understanding of lake variations in arid regions. In this study, we combined the land surface model and hydrological model, as well as statistical methods, to analyze the spatiotemporal heterogeneity of lake area changes and the factors affecting these changes during the past decades in Bosten Lake, Ulungur Lake, Ebinur Lake, and Sayram Lake, which are located in a typical dry region in China. The study revealed that the average amounts of river inflow, TWVF, lake ice sublimation, lake surface precipitation, and river outflow in the four lakes were 17.41 × 10⁸ m³ yr⁻¹, 6.60 × 10⁸ m³ yr⁻¹, 0.41 × 10⁸ m³ yr⁻¹, 0.98 × 10⁸ m³ yr⁻¹, and 9.12 × 10⁸ m³ yr⁻¹, respectively. We found that river inflow is the dominant factor affecting changes in open lake areas, while lake surface precipitation is the main factor affecting changes in closed lake areas. Our findings suggest that the main factors dominating the variability of lake water volume differ in different phases and lake types.

Throughfall makes up the major portion of understory rainfall, and thereby plays a vital role in regulating the hydrological and biogeochemical processes in forest ecosystems. The aim of this study was to explore the alterations in throughfall and the associated chemical composition (Ca²⁺, Na²⁺, K⁺, Mg²⁺, H⁺, SO₄²⁻, NO₃⁻, Cl⁻, and F⁻) under Quercus acutissima Carruth. and Broussonetia papyrifera (L.) L’Her. ex Vent. trees, in relation to trunk distance and rainfall characteristics. Event-based measurements were carried out from April to December 2018 in a subtropical forest of eastern China. The throughfall amount (T_F) and throughfall ratio (T_F%) of Q. acutissima (35.7 mm, 83.0%) were higher than those of B. papyrifera (32.1 mm, 74.7%). Although no significant species differences in the ion concentrations of throughfall were detected, almost all ions (Ca²⁺, Na²⁺, K⁺, Mg²⁺, H⁺, SO₄²⁻, NO₃⁻, and Cl⁻) were enriched after passing through the canopies of the two tree species. T_F and T_F% increased with increasing distance from the trunk, while the concentrations of most ions in throughfall increased, since the trunk was approximated. Regression analysis and redundancy analysis revealed that rainfall amount, duration and intensity exerted significant impacts on throughfall generation and ion concentrations, and the antecedent dry period had a notable influence only on ion concentrations. Our findings indicated that forest canopy and rainfall characteristics play an important role in the alterations in throughfall and the associated chemical compositions.

Hourly scale hydrological modeling holds pivotal significance for flood-related research, as watershed floods often occur within a few hours of intense rainfall. Although the SWAT model’s hourly simulation has found application in a few watersheds, the relatively short usage history and limited scope inhibit a comprehensive grasp of its potential. In this study, a coastal watershed in Fukuyama City, Japan was selected as a case study for conducting hourly simulations. The study highlights the hourly simulation’s proficiency in capturing diverse flood trends while also accurately replicating baseflow and flood peaks within the 0 to 200 m³/s range. However, there is an underestimation of peak flows in calculations exceeding 200 m³/s. Moreover, empirical summaries have been generated to outline the parameterization process of hourly simulation, revealing how distinct parameters influence simulated runoff. For instance, it outlines how BFLO_DIST significantly affects baseflow simulation when operating in hourly mode. Our findings provide an empirical summary of the advantages, disadvantages, and parameterization process for hourly simulations of the SWAT model.