立地条件对落叶松人工林生长的影响

通过对日本落叶松(Larix kaempferi)人工林在不同立地条件下的生长调查,结果表明,日本落叶松在生长过程中,受土层厚度、林地位置、立地指数等多方面因素的制约:厚层土胸径年生长量比中层土和薄层土高9.2%～26.7%,树高年生长量高21.8%～44%;生长在N坡,坡度较缓、山地下腹为优;在不同的立地指数级中,生长差异明显,18以上指数级比14～18指数级胸径生长量高25.4%,比14以下指数级胸径生长量高33.8%,树高生长量,18以上指数级比14～18指数级高26.7%,比14以下指数级高36.3%。培育日本落叶松人工林,选择优质立地条件不但可提高林木的生长速度,又能促使林木优质高产。

Effect of Site Conditions on Growth of Larix kaempferi Plantation

Through investigations on growth of Larix kaempferi under different site conditions,result shows that: Larix kaempferi were inhibited with soil thickness,woodland location,site index,and many other factors in the growth process :annual growth of DBH,annual tree height growth for the thick layer of soil are 9.2%-26.7%,21.8%-44% higher than that of middle & thin layer of soil;it grows optimal in the shady,gentler slope at the lower mountain;under different site index level,the growth differences are significant;DBH increment with more than 18 index level are 25.4%,33.8% higher than that with 14-18 & less than 14 index level;tree height growth with more than 18 index level are 26.7%,36.3% higher than that with 14-18 & less than 14 index level;cultivating Larix kaempferi plantations by selecting high-quality site conditions not only can increase the growth rate of the trees,but also can promote the forest quality and high yield.