A novel structural equation modelling-based framework for identifying hydrometeorological multi-factor interaction

The Hanjiang River Basin, China. In this study, we proposed a new integrated framework based on structural equation models to identify hydrometeorological multi-factor interaction relationship. The spatiotemporal distribution and interaction relationship of hydrological, meteorological, and vegetation indicators in the Hanjiang River Basin were analyzed based on the national long-series monitoring data. The findings reveal that: (1) The rainfall is the maximum in the lower reaches (968.87 mm), and the runoff depth fluctuated the most in the lower reaches (1181.70 mm to 2934.88 mm). (2) Dew point temperature is an important influencing factor of rainfall in the upper and middle reaches, and relative humidity is an important influencing factor of rainfall in the lower reaches. High vegetation cover is an important influencing factor for runoff depth. (3) Rainfall and runoff depth are significantly negatively affected by meteorological characteristics, with effect values ranging from −0.24 to −0.68. However, runoff depth is positively affected by rainfall, relative humidity, vegetation characteristics, and canopy interception, with effect values ranging from 0.02 to 0.58. The size and mode of influence have significant regional differences. • Driving factors of rainfall and runoff depth are identified by Mantel's test. • Meteorological characteristics have negative effects on rainfall and runoff depth. • Rainfall and relative humidity have positive effects on runoff depth. • Canopy interception has only a positive direct effect on runoff depth in all areas.