太行山林区中部土壤养分对油松人工林生长的影响

根据太行山林区中部海拔１２００—１３００ｍ阴坡２１年生油松人工林内１２块标准地调查材料、林地土壤中氮、磷、钾养分含量测定和７４株油松样木针叶营养元素含量的测定，分析了林地土壤氮、磷、钾养分对油松林木生长的影响，结果表明，立地等级低的油松人工林分，林地土壤中近期内可利用的养分缺乏，水解性氮和速效磷供应不足，影响了油松林木的生长；林地土壤ｐＨ的增高，会降低土壤中速效养分的有效性，从而影响林木的生长。

Effects of Soil Nutrient on the Growth of Pinus Tabulaeformis Artificial Forest of Central Section of Taihang Mountain

Soil samples were taken from 12 stands of Pinus tabulaeformis according to different dominant height,which distribute on the north side of hill with an altitute of 1200 1300m above sea level in the central section of Taihang mountain.The contents of organic matter,nitrogen and effective N,phosphorus and effective P,potassium and effective K,and pH were analysed.Meanwhile,needles samples were also taken from 74 pinus trees in the 12 plots and were analysed for N,P,K,Ca and Mg. According to findings of the plots and analytical results,the contents of soil nutrient are different from each stands.The result indicates that the contents of effective N,effective P are lower in soil.This is unfavourable for the growth of pinus trees.And high pH has harmful effects upon growth for trees,because high pH can reduce the effectiveness of other nutrient,such as P,Fe,B,Zn,Mn etc. There is correlation between the dominant height and the nutrient confent of needles.This showed that N.P and K are main factors for the growth of trees.But,the contents of soil nutrients are lower,especially N and P,in the research area.To increase soil fertility,mixed forest should be set up,mycorrhize should be inoculated,and artificial fertilizer should be used in the pinus tabulaeformis forest of Taihang mountain.