Study On The Theoretical Technology Of Plant Drought-Resistance And Its Applaction On Vegetation Restoration In Arid Region

The northwest arid area of china is a water-deficient and eco-environmental fragile area. The vegetation restoration and rehabilitation faces a severe challenge with the global warming and climatic evolution. Drought has become one of the major environmental stressor influencing the distribution, growth and development of plants seriously. Water stress is one of most important environmental factors which restrict the growth of plant. Studying and exploring the drought-resistant afforestation technology suitable for arid and semi-arid region, reducing water loss in the soil and increasing the afforestation survival rate have become the global focus.This paper overviews the research results and related literatures mechanisms and research progress of plant drought resistance and its mechanism at home and abroad from the aspect of plant configuration, growth status and physiological and biochemical indexes. Under the drought stress, the plant anatomical structure of plant and physiological and biochemical indexes changed remarkably and caused a series of physiological and biochemical reaction. This essay discussed the physiological and biochemical reaction, anatomical structure and self-regulation mechanism of trees under adversity conditions, elaborated the relationship between deferent stages of plant growth and development and drought-resistant ability and pointed out the significance of strengthen the whole drought-resistant ability of plant under the drought stress.The application of new drought-resistant afforestation technology can reduce the evaporation of soil water and keep the soil water rate at a high level, guarantee the water supplication of the tree roots in the arid period, maintain the survival of the tree and improve the afforestation survival rate obviously. We made a field comparative test on afforestation survival rate of locust by using plastic film, Genbao, ABT Rooting Powder, water retaining agent, and the survival rates are 84.46%,77.19%,70.61%,62.03% respectively, which is much higher than that in the control treatment. The result shows that effect of all these drought-resistant afforestation technology have a obvious impact on increasing the afforestation survival rate, but the former two are more significant in increasing the forestation survival rate while there is no significant difference between the treatment of ABT Rooting Powder, water retaining agent and the control treatment. Applications of plastic film, Genbao not only can increase the afforestation survival rate, but also have a higher stability than that of the ABT Rooting Powder and water retaining agent.In conclusion, this paper analyzes the issue and its countermeasures of vegetation restoration and rehabilitation in the arid and semi-arid region, taking Jiayuguan City as an example: (1) The vegetation rehabilitation around cities should be based on the zonal distribution pattern of vegetations and regional eco-environment status, adapt to local conditions and collocate suitable fine tree species on the base of the site conditions. Meanwhile, we should apply the water saving and drought-resistance technology actively, and solve the problems of low survival and preserving rate that affect the harness benefit; (2) Vegetation restoration should be based on the small watershed comprehensive management, strengthen the construction of farmland, artificial grassland and water-soil conservation project and resolve the contradiction between the vegetation construction land and producing and living land.