【摘要】 <正> 一、试验目的 我国的育苗工作,在东北地区50年代培育针叶树苗多数是采取控光育苗的。60年代后,逐渐取消了控光,采用全光育苗,这在大面积育苗生产过程中既省物资又省劳力,因而受到生产部门的欢迎,这是必然的。但引起苗床土壤板结甚至冲刷,耗水量亦大,更多还原

【Abstract】 The paper is about results made by the authors who worked in Heping Nursery of Xing Long Forestry Office of Heilongjiang province during 1984—1986 with different rates of covering sunlight to treat the growing seedlings of korean pine, It has proved that the quantity and quality of korean pine seedlings are quite obvious when different rates of covering sunlight and different ways of sunshading was taken during their three years’ growing. 30—50% of covering sunlight has better effect in the first arid second growing seasons of korean pine seedlins; 10—30% of covering sunlight has better effect in third growing season during daytime, covering strong sunlight (native time : 10 a. m. to 4 p. m. has much. better effect than covering them whole day.更多还原