土壤掩埋对辽东栎幼苗出土和生长的影响

以黄土高原天然次生林辽东栎（Quercus wutaishanica）种子为对象，采用双因素（覆土厚度和播种时间）完全随机试验的方法，研究土壤掩埋对辽东栎幼苗出土和生长的影响。结果表明：① 覆土厚度对辽东栎种子的出苗率有显著影响(P<0.05)，出苗率随着覆土厚度的增加而增加，覆土厚度为10 cm时，出苗率达到最大值，分别为（53.2±20.7）%和（42.0±0.7）%；覆土厚度对幼苗的生长影响不显著。② 播种时间对0~3 cm覆土播种的出苗率影响显著(P<0.05)，由于温度的差异，11月1日播种的种子出苗率高于12月10日，出苗率分别为（11.9±1.2）%~（53.2±20.7）%和（1.5±0.8）%~（42.0±0.7）%；播种时间对覆土播种的幼苗生长无显著影响，对地表播种的幼苗叶面积影响显著（P<0.05）。可见，土壤掩埋有利于辽东栎幼苗的出土，土壤掩埋对幼苗的生长影响不大。

Effects of Soil covering Thickness on Emergence Rate and Seedling Growth ofQuercus wutaishanica

In this study, the effects of soil covering thickness and sowing time on the emergence rate and seedling growth of WTBX]Quercus wutaishanica,WTBZ] a kind of natural secondary forest on the Loess Plateau, were researched. The results were as follows: ① Soil covering thickness affected significantly the emergence rate WTBX](P<0.05),WTBZ] the emergence rate was increased with the increase of soil covering thickness and reached its maximum value when the soil covering thickness was increased to 10 cm. The effect of soil covering thickness on the seedling growth was not significant; ② The effect of sowing time on the emergence rate was significant when the soil covering thickness was 0-3 cm WTBX](P<0.05).WTBZ] The emergence rate that the sowing time was on November 1 was higher than that on December 10 because of the temperature difference, and the emergence rates that the sowing time was on these two days were (11.9±1.2)%-(53.2±20.7)% and (1.5 %±0.8)%-(42.0±0.7)% respectively; the effect of sowing time on the seedling growth was not significant but the leaf area WTBX](P<0.05).WTBZ] Therefore, it could be concluded that soil covering was advantageous for improving the emergence rate of WTBX]Q. wutaishanica,WTBZ] but its effect on the seedling growth was not significant.