供水对黄土高原主要造林树种生长的影响

采用人工供水的方法，研究了水分条件对黄土高原主要造林树种(油松、侧柏、刺槐)生长的影响。结果表明，供水促进了树木的生长，油松在1．0倍处理时，树高、胸径、材积增加最大；侧柏在1．0倍和1．5倍处理时，分别对树高和胸径影响最大，材积在1．5倍处理时效果最显著；1．5倍供水处理下，刺槐胸径和材积增幅最大。生长季中，油松和刺槐的适宜灌溉水平为2．1～2．4m^3／株，侧柏为1．2～2．1m^3／株。

The Influence of Water Supplement for Growth of Trees on the Loess Plateau

The influence of water for growth of trees on the loess plateau were studied by irrigation. The results showed that irrigation accelerated the growth of the trees. When the irrigation lever were 1. 5,1. 0,0. 5 times of precipitation and control, the height,diameter and volume of Pinus tabulae formis were greatly creased at the lever of 1. 0 time, and those of Platydadus oriental's were at 1.0,1. 5,1. 5 times respectively. The diameter and volume of Robina pseudoacacia were increased obviously at 1. 5 times of precipitation. The suitable water of irrigation of Pinus tabulaeformis and Robina pseudoacacia were 2. 1-2. 4 m3,and Platydadus orientalis were 1. 2-2.1 m3 per tree respectively during the growing season.