Effects of sand-burial depth on Leymus chinensis seedlings emergence and growth
四种沙埋深度对羊草种子出苗和幼苗生长的影响

To investigate the effects of burial depth on the Leymus chinensis seedlings emergence and growth under natural conditions,a simulation study was conducted with four sand-burial depths(0,1,2 and 3 cm).The results showed that the seedlings emergence rate decreased with increasing burial depth,being 89.3%,81.5%,78.5% and 73.5% when the burial depths were 0,1,2 and 3 cm,respectively.During the first 25 days of growth,the aboveground plant height was higher in the treatments of 0-2 cm burial depth than in that of 3 cm burial depth,but no significant difference was observed among the four treatments by the end of the experiment(36 days after growth).With the increase of burial depth,the root length and number and the root/shoot ratio increased first but decreased then,leaf number decreased,and seedlings absolute height increased.It could be concluded that a sand-burial depth of 1-2 cm could be more suitable to the L.chinensis seedlings emergence and growth,while the burial depths of 0 and 3 cm could be unfavorable to the emergence and growth.