Abstract:

In order to improve the afforestation survival percentage, and the strategies for the increase of water use efficiency, promote better growth of trees, to provide some theoretical basis for vegetation construction in semi-arid valley of Tibet, the planting test was established at the semi-arid valleys land in Tibet, using different silvicultural techniques, such as covering stone, covering film, covering straw, covering egg-tray and using water retaining agent. The author researched the changes in physiological and biochemical indexes of sea buckthorn leaves in different measures. The results showed that: to some extent, different measures had increased the survival rate, the relative water content and chlorophyll content in leaves were improved under the different measures, but the contents of soluble sugar, malondiadehyde and proline in leaves were increased. It was showed the introduction of new silvicultural techniques played an irreplaceable role in improving the survival rate in arid regions, increasing water use efficiency and promoting better growth of trees in semi-arid valleys land.