Growth Response of Pinus densiflora, Larix leptolepis, Betula platyphylla var. japonica and Quercus acutissima Seedlings at Various Levels of Fertilization

摘要

We have only one type of forest fertilizer involved a composition ratio of 12:16:4% (N:P:K). It is required to develop new fertilization ratios which are suitable to soil environmental conditions and seedling growth characteristics. This study was carried out to determine change of seedlings growth on different fertilizer composition ratios. Two coniferous seedlings (2-year old Pinus densiflora Sieb. et Zucc., 2-year old Larix leptolepis Gordon) and two deciduous seedlings (2-year old Quercus acutissima Carruth., 1-year old Betula platyphylla var. japonica Kara) were planted in pots (about 30 ) and the seedling growth responses after composition ratio treatments (N:P:K, 2:2:1, 3:4:1, 3:8:1, 6:4:1, 3;4:2, control) with 30g fertilizer were measured ,for three-year study period. Growth of height and root collar diameter of two coniferous seedlings was highest in 3:8:1 ratio compared with other fertilizer composition treatments or control, while there was not significantly different among fertilizer composition ratios except for 2:2:1 and 3:4:1 ratios. Height growth of two deciduous seedlings was highest in 3:8:1 ratio compared with other fertilizer composition treatments or control, while growth of root collar diameter showed the highest values in 6