关键词: 樟子松幼树, 沙埋, 生长, 影响, 适应

Abstract: There is a great deal of literatures on the effects of sand burial upon the survival and growth of desert plants, but the effects of sand burial on survival of Pinus sylvestnis var. mongolica saplings and its growth adaption to sand burial have as yet rarely been studied. P. sylvestnis var. mongolica is an evergreen species planted most widely in the desert areas of northern China. In order to understand effects of sand burial on growth properties of P. sylvestnis var. mongolica saplings, changes of survival rate, plant height, stem diameter, terminal bud length, canopy areas of P. sylvestnis var. mongolica saplings in different sand burial depths were studies during 2013 in the Horqin Sandy Land of Inner Mongolia. The results showed that the maximum tolerance of the saplings to sand burial is 2 cm depth above plant height, the survival rates of saplings began falling when the burial depth was 2 cm above the plant height, and the all saplings died after the burial depth exceeded 2 cm above the plant height. Sand burial below 2cm above the plant height could promote height growth and stem diameter growth of the saplings, in which the increased magnitudes were largest in the burial depth being 1/4 and 1/2 plant height. Similarly, sand burial below 2 cm above the plant height also could promote terminal bud growth of the saplings, but the increased magnitudes were largest in the burial depth being 3/4 and 4/4 plant height. Sand burial could result in a decrease of the plant canopy, but the differences were not significantly among the canopies at the burial treatments and no burial treatment. Promoting effect of the partial burial to the sapling growth may be attributed to decrease of soil temperature and a increase of soil moisture in the root layer resulted from sand burial, the main reason of complete burial to result in death of the sapling could attributed to a decrease of photosynthetic area and rot of leaf without breathe after sand burial.

Key words: Pinus sylvestnis var. mongolica saplings, sand burial, growth, effects, adaptation