Qin, W.J. and Fan, G.S., 2020. Estimating soil water characteristic curve from soil physical-chemical properties in alluvial plain. In: Bai, X. and Zhou, H. (eds.), Advances in Water Resources, Environmental Protection, and Sustainable Development. Journal of Coastal Research, Special Issue No. 115, pp. 421-424. Coconut Creek (Florida), ISSN 0749-0208. The soil water characteristic curve is an important equation of soil hydraulics, which plays a decisive role in the storage and transport of soil water, and has potential influences of hydrological and ecological processes in whole ecosystems. In order to understand the controlling factors affect Van Genuchten model parameters in Alluvial Plain, ninety undisturbed soil samples were collected from Chanyuan River and Xishan Lake. The direct determination of the soil water characteristic curve has the defects of time-consuming and high cost, the BP based on genetic algorithm optimization model was proposed to obtain the Van Genuchten model parameters from easily-obtained soil physical-chemical properties. The research results provide a basis for the further study of soil water holding capacity of undisturbed soil, and also provide a more accurate method for obtaining soil water characteristic curve in Alluvial Plain. [ABSTRACT FROM AUTHOR]