抄録
The effect of stand density to soil infiltration rate was assessed in this study. The study site was in the Ehime University Forests, Ehime Prefecture, Shikoku Island, Japan. Soil samples were taken and brought to the laboratory for further laboratory works to determine soil infiltration rate. Eleven treatments were identified according to the forest type/species: natural forests Japanese cedar and cypress plantations with relative yield index (Ry) ranging from 0.37 to 0.95. Three sampling sites were established for each treatment with 3 replicates. Samples were taken from both topsoil and subsoil. Data analysis was conducted using the Statistical Package for the Social Sciences using the General Linear Model Analysis of Variance (One-way Anova) to test whether infiltration rate was statistically different in the eleven treatments. Tukey Honestly Significant Difference was used to compare means in case of significance (p<0.05). Results showed that in topsoil the highest infiltration rate among the forest plantation was found in Japanese cedar and cypress having relative yield between 0.50 and 0.60 and comparable to that of natural forests Those areas without forest operations and having high relative yield (Ry : 0.70 and above) showed the lowest values. There was almost no significant difference for subsoil except slight high infiltration rate for natural forest and Japanese cedar with Ry of 0.50 to 0.60. These results indicate the need of forest operations and the importance of stand density control, a guarantee for a better soil physical property, in particular soil infiltration rate.
https://ror.org/017hkng22 
