| The apple trees of different pruning intensity(mild degree,moderate degree and heavy degree) and different tree age(5 years old,11 years old and 16 years old) and the different shape of tree canopy(open center shape,spindle shape and disperse lamination shape) were selected to study in apple orchard in the Luo-chuan County,Shaanxi Province.The canopy characteristics and the relative light radiation were studied by the plant canopy hemispherical photographs system.The results showed that,the heavy degree tree effectively increased the light penetration.Along with the tree age increasing,the LAI increased,and it was advantageous in the interception radiation energy,but the light-admitting quality reduced simultaneously.Compared with other kinds of shapes of trees,the open center shape trees were more able to increase the light-admitting quality,and raised the light use efficiency. |