Abstract:

Effects of preparation methods on seedling regeneration process of direct seeding of Picea schrenkiana var. tianschanica were analyzed in order to explore suitable preparation methods for the direct seeding of P. schrenkiana var. tianschanica. Taking direct seeding of P. schrenkiana var. tianschanica in sparse degraded forest land as the object, one-way analysis of variance (ANOVA) and Fisher’s least significance difference (LSD) method were used to test the difference of seedling emergence rate and seedling establishment rate of P. schrenkiana var. tianschanica in different preparation methods. The survival curve of direct seeding of P. schrenkiana var. tianschanica in different preparation methods was estimated by the Kaplan-Meier method, and the difference of seedling survival distribution was compared by the K sample test and the Log-rank test with censored data. The seedling emergence rate was highest when the preparation method exposing soil B layer, followed by topsoil biochar addition, and the seedling emergence rate was lowest at the soil mound accumulation. There were significant differences in emergence rate among the three preparation methods(P=0.000<0.01). The seedling survival rate was significantly higher in the preparation methods that exposing soil B layer and topsoil biochar addition compared to the soil mound accumulation (P=0.000<0.01). There was no significant difference in seedling survival rate between the preparation methods that exposing soil B layer and topsoil biochar addition (P=0.114>0.05). The survival probability of the preparation methods that exposing soil B layer and topsoil biochar addition was significantly higher than that of the soil mound accumulation (P=0.000<0.01), and the survival probability of the preparation method that exposing soil B layer was no significant difference with that of topsoil biochar addition (P=0.268>0.05). Suitable preparation methods can promote the direct seeding of P. schrenkiana var. tianschanica in sparse degraded forest land. Among them, exposing soil B layer is the most suitable preparation method for the direct seeding.

Key words: Picea schrenkiana var. tianschanica, preparation methods, direct seeding, seedling emergence, seedling establishment, variance analysis, Kaplan-Meier method