Overland Flow Resistance Law under Sparse Stem Vegetation Coverage

To explore the characteristics of overland flow resistance under condition sparse vegetative stem coverage and improve basic theoretical research flow, were systematically investigated four slope gradients (S), seven discharges (Q), six degrees vegetation (Cr). The results show that Manning roughness coefficient (n) changes with ratio water depth to height (h/hv) while Reynolds number (Re), Froude (Fr), (S) are closely related coverage. Meanwhile, h/hv, Re, Cr have strong positive correlations n, Fr S negative n. Through data regression analysis, a power function relationship between n hydraulic parameters was observed sensitivity analysis performed. It concluded Cr, Q, shows same law; in particular, for coverage, is dominant factor affecting zero condition, no longer first non-zero condition. In Fr, has least effect on resistance. This indicates when correlated different parameters, effects Therefore, it necessary study stalk