Fo1lowing hydrodynamic tenets,an energetic eqtiation model is prepared for canopy-level turbulence with the restilts verified against measurements from wheat and corn fields.

The leaf area index(LAI) of vegetation is one of the most important structure parameters used in the ecological system studies and one of the key parameters used in estimating the varied function process of vegetation canopy.

LAI of different kinds of vegetations in the study area have been derived from the gap fraction of vegetation canopy.

The spatial distribution of solar radiation in a plant canopy influences eco-physiological functions and gives a measure of the light-interception efficiency of stand architecture.