关键词: 樟子松, 人工林, 群落结构, 土壤水分, 稳定性

Abstract:

The community structure and dynamics of soil water of Pinus sylvestris var. Mongolica plantation were studied in a growth season. The results showed that the soil water in 300 cm depth were almost run out, with the soil water content being only 0.82%～0.97%. Moreover, soil water content continually decreased over the whole growth season. The growth of 13-year-old P. sylvestris var.Mongolica plantation was very weak, the average tree height was only 3.59 m, and the average diameter at breast height only 5.77 cm. Growth of trees was strongly restrained by shortage of soil water. The herbaceous layer under tree layer developed well. The species richness of herbaceous layer was 7～8 species per m², and the Shannon-wiener index was 1.59～1.89, with a high coverage of 54.7%～65.4%. It is a trend that the plantation will be replaced by herb layer. Also the stability of plantation was analyzed, pointing out that, the depletion of soil water can be alleviated through density control, tree species selection, etc. Under the condition that underground water is available and can be used by plants, the stability of plantation can be maintained over one generation.

Key words: Pinus sylvestris var. Mongolica , plantation, community structure, soil water, stability