奪葉圧の数量的指標 : 定義と適用

抄録

where ALL_<ST> stands for the Average Leaf Longevity (ALL) of the undefoliated plant and ALL_h means that of a mechanically defoliated plant h which is otherwise under the same conditions as the undefoliated Standard. DPX can take account of the three factors, timing, frequency and severity, of the intensity of defoliation pressure in one term. The application of DPX in some practical cases clearly demonstrated negative correlations between DPX and variables such as the standing crop of leaf area in the following early growing stage, volumetric wood growth of young tamaracks, average annual yield of range grass. These results suggest that DPX is strongly applicable in examining various aspects of ecosystem where defoliation, whether by intention or by chance, plays a crucial role.