旱区限量灌水造林对幼苗建成的影响

Effects of Limite Irrigation on Seedling Establishment in Arid Areas

以阳坡为主,采用小区对比试验的方法,对限量灌水造林进行了研究。结果表明,限量灌水通过增加土壤水分有利于幼苗建成,可促进幼苗早期萌发、成活及生长。覆盖对灌水有增进作用,其中地膜覆盖优于土壤覆盖。但与阳坡相比,阴坡灌水量较高时存在例外。表明阴坡造林以少灌为宜,而阳坡造林可适当多灌。幼苗根系深度以及叶片含水量与其地上部分的生长相一致。灌水使得根系向下延伸是幼苗成活及稳定生长的关键因素。

Effects of limited irrigation on seedling establishment in the arid areas were studied by plot comparative test being carried out maialy on sunny slopes. The results showed that the limited irrigation was favourable for the seedling establishment through increasing soil moisture. The early shooting, surviving and growth of the seedling may be enhanced. The promotion to the irrigation was produced by the mulches, of which the plastic film was better than the soil. But there is an exception in the shady slope when the irrigating water was more, compared with the case in the sunny slope, indicating that in shady slope less water should be given to the seedlings, while in the sunny slope suitably more water might be used. The root depth and leaf water content of the seedlings accorded with the growth of the stem. It is a key factor to the seedling survival and stable growth that irrigation makes the root run downwards in the soil.