Abstract:To investigate the effects of soil hydraulic parameters on the long-range correlation of soil moisture under different climatic conditions, a 1-D vadose zone model (HYDRUS-1D) was utilized to simulate soil moisture time series under different climatic conditions in China (humid area, semi-arid area, and arid area) using generated soil hydraulic parameters datasets for sandy and clay loam soils. Then, the long-range correlation of soil moisture data was calculated by detrend fluctuation analysis. The results showed that: (1) The scale exponent (h) of the simulated soil moisture ranged from 0.570 to 1.915, indicating that there was an obvious long-range correlation. Soil moisture time series was mainly characterized by persistence for sandy, but for clay loam, there were both persistence and anti-persistence. (2) The long-range correlation was positively correlated with the soil depth, clay fraction, and aridity index. (3) The main soil hydraulic parameters affecting long-range correlation were n, α, and Ks. Specifically, n was the main hydraulic parameter affecting long-range correlation for sandy soils at all locations. For clay loam soils, α was the predominant hydraulic parameter affecting long-range correlation in humid area, α and Ks were the main hydraulic parameters affecting long-range correlation in semi-arid and arid areas. The results can provide some reference for revealing the long-term evolution mechanism of soil moisture.