油松和侧柏人工林适宜灌溉定额的研究

Study on Suitable Irrigation Norms of Pinus tabulaeformis and Platycladus orientalis Plantation

采用人工灌水的方法 ,研究 2 0年生油松和侧柏人工林的耗水特性及水分利用效率 ,确定其适宜的灌溉定额。结果表明 ,油松和侧柏的耗水量与其灌水水平呈正相关 :平水年 ,1 5、1 0、0 5倍降水量的灌水水平和对照条件下 ,5— 10月份 ,油松的耗水量分别为 10 35 8.5、82 90 .5、6 4 5 5 .5、4 337 0m3·hm- 2 ,侧柏为 95 4 7 5、7980 0、6 4 71 0、4 195 0m3·hm- 2 。灌水促进了树木的生长 ,油松在 1 0倍灌水处理时 ,树高、胸径、材积增加最大 ,侧柏在1 0～ 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 ;油松在 1 0倍处理时 ,水分利用效率最高 ,而侧柏则在 1 0～ 1 5倍处理为宜 ;生长季中 ,油松和侧柏的适宜灌溉定额分别为 5 2 5 0～ 6 0 0 0m3·hm- 2和 5 330～ 9330m3·hm- 2 ,分 3次进行灌溉。

The characteristic of water consumption and water utilization efficiency of 20 year old Pinus tabulaeformis and Platycladus orientalis plantation were studied by artificial irrigating. The results shown that there was positive correlation between the water consumption and irrigation.When the irrigation level were 1.5, 1.0, 0.5 time of precipitation and control, the water consurnption of Pinus tabulaeformis were 10 358.5, 8 290.5, 6 455.5, 4 337.0 m3·hm -2 respectively, and Platycladus orientalis were 9 547.5, 7 980.0, 6 471.0, 4 195.0 m3·hm -2 respectively. Irrigation accelerated the growth of the trees. The hight, diameter at breast height and volume of Pinus tabulaeformis were greatly increased at the level of 1.0 time, and those of Platycladus orientalis were at 1.0, 1.5, 1.5 time. The water utitization efficiency of Pinus tabulaeformis and Platycladus orientalis were highest at the level of 1.0 time and 1.0～1.5 time respectively, and the suitale water of irrigation were 5 250～6 000 m3·hm -2 and 5 330～9 330 m3·hm -2 per tree respectively from March to October, which were divided into 3 times.