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Sensible heat flux, latent heat flux and momentum flux on heavy grazing site, medium grazing site, light grazing site, no grazing site, dune, grassland and maize site underlying surfaces, according to the variational method, the conventional Bowen ratio energy balance method and the aerodynamic method, have been computed by utilizing the micrometeorological observed data of dune and vegetation at the semi-arid area at Naiman in Inner Mongolia of China between 1990 similar to 1994. The results show that the turbulent fluxes calculated by three methods are comparatively consistent at the most time, which have close correlation and closure degree of the energy balance except on the dune and heavy grazing site. So the variational method will be more applicable at the flourishing underling surface. And also, above-ground biomass, plant coverage, height of vegetation, momentum flux and latent heat flux decreases, along with the increasing of the grazing intensity, which corresponds to the enhancing of sensible heat flux. Flourishing underling surface could increase the vertical momentum transportation and aerodynamic roughness length,decrease the wind speed, prevent the movement of the sand and the fluctuation of dune, and so avoid desertification to a certain degree.