不同立地类型对引种美洲黑杨生长的影响

Effects of Different Site Conditions on the Growth of Introduced Populus deltoides

分别选取农地、河岸、半山坡、山坡中上部、箐沟以及不同地下水位平地等立地类型,开展引种美洲黑杨的生长状况观测。结果表明,在不同立地类型下美洲黑杨的保存率存在明显差异,其中,在农地栽种的美洲黑杨保存率最高,在98.0%以上;其次为河岸、地下水位在100 cm的平地,保存率在97.0%左右;山坡中上部地区栽种的美洲黑杨保存率最低,仅为52.8%。不同立地类型对3年生美洲黑杨的树高、胸径和冠幅具有极显著的影响,在农地、地下水位约100 cm的平地、河岸栽种的美洲黑杨生长量较大,而在地下水位高于50cm的平地、半山坡及山坡中上部地区的生长势较差,表明美洲黑杨耐涝和耐旱能力较弱,也不宜上山栽种。

Selecting farmland, fiver bank, hillside farmland, upper part of mountain, Jinggou, different underground water level site type, observation on growth status of introduced Populus deltoides was carried out. The results showed that there were significant differences in the preservation rate of P. deltoides in different site types, among them, the preservation rate of P. deltoides cultivated in farmland was highest, above 98.0% ; the second was on both river bank and underground water level at 100 cm, the preservation rate was about 97.0% ; on the up- per part of the mountain area, the preservation rate of P. deltoides was lowest, only 52.8%. Different site types had significant effects on tree height, DBH and crown growth amount of 3a P. deltoides, the growth amount of P. deltoides cultivated in farmland, underground water level about 100 cm ground, both sides of the fiver bank were larger, while the growth potential of P. deltoides on the underground water level above 50 cm ground, hillside farmland and upper part of mountain was poor. It was indicated that the ability of waterlogging and drought resistance of P. deltoides was weak, and it should not to be planted in the mountains.