Abstract: Quantitative study of non-point source pollution is of significance in effective management of water quality. Export coefficient method, owing to its relatively fewer data input requirement, simple structure, and easy application, was widely used in the study of agricultural non-point source pollution, and obtained greater development. This paper introduced the development process of export coefficient model and its application in estimating agricultural non-point source pollutant load, and generalized the acquirement approaches of pollutant export coefficients and their values under different conditions. The scale effect of export coefficient, the coupling of export coefficient mode with hydrological model were proposed as the main study areas of the export coefficient models in the future.

Key words: Hibiscus cannabinus, Plant height, Stem diameter, Developmental genetics, Genetics effect