Study On Technology Of Big Tree Transplant In City's Landscaping Project In Northwest China

Improving the city's living environment and greening level have been a important task of city construction. With the rapid development of urbanization in most cities of China, the big tree transplanting project is needed to do landscape greening well and improve the city's landscape in a short time. In order to improve the city's environment and landscape of northwest China's cities, the technologies of big tree transplantation are studied based on the current situation of city's landscape greening in northwest of China. Through the study of big tree transplanting technology, on the one hand, the survival rate of the transplanted trees can be improved, and also the precious big tree's resources are protected. On the other hand, at present, the cost of the measures is very high to guarantee survival of big tree transplantation, so studying the technology of the survival guarantee of big tree transplantation can reduce the unnecessary waste. Especially, with the rapid city development and construction under the project of Western Development, how to protect and use the original city's big tree resources at the utmost extent, and how to improve the survival rate of foreign big tree transplantation, and how to regulate the operating technology of big tree transplantation during the execution of landscape green, which have become the urgent research project.In this paper, defoliated formed trees that the diameters are between 15 to 60 centimeters and ever-green formed trees that the diameters are between 15 to 40 centimeters are chosen for research. Through researching and investigating the current situation of landscape greening in northwest of China, the basis theory of big tree transplantation are discussed. Meanwhile, the techniques of big tree transplantation which are fit for northwest of China are researched. And also, based on the practical landscape green projects, the key techniques that can improve the survival rates of big tree transplantation of northwest of China are put forward and summarized. These key techniques are summarized as following:1. Techniques of big tree transplantation(1) Advance-phrase preparation: Ascertain the optimum tree species, and then clear about the date of big tree transplanting. After being definite about the date, according to the principle of digging quickly, transporting quickly, planting quickly, the survival rate are avoided to be decrease because of the insufficient preparation. Then, the planting place, the size of tree well and changing the soil or not should be confirmed. And also, the surround space should be cleaned to assure that machines have enough operating space. (2) Tree lifting: For transplanting those big trees in non-transplanting season, soil should be kept on the roots when transplanting. (3) Pruning: The aim of pruning is to decrease the evaporation of the tree's water, make transportation and transplantation conveniently. (4) Transportation: When transporting, the big trees should keep a fixed slope; when putting big trees to the ground, brace should be made. (5) Planting: When planting, big trees should keep straight and right orientation. After planted, water should be irrigated in time. In the first time of water irrigating, soil should be enough wet. Also, some other measures should be taken, such as water spraying for tree crown, temporary shading. In addition, growth substances, like NAA, can be used to promote new roots grow from the damaged roots; Anti-evaporation materials can be sprayed or pasted on the stems of big trees, which can also decrease the evaporation, and finally improve the survival rate of big tree transplantation.2. Raising and management after transplanted(1) Water keeping: For new transplanted big trees, because roots are very easy to be damaged, and the capability of water absorbing is also decreased, so keeping water balance is the key factor to assure the survival. (2) Control diseases and insect pests: Because of lower diseases and insect resistance, frequent observing and taking preventing measures in time are necessary. (3) Draining water: Such as, for deodar cedar, too wet and high ground water are tabooed, and in rain season, draining water should be paid attention to; for chenars, water should be irrigated much more after transplanted. (4) Prevent high temperature in summer and prevent too cold in winter: In northwest of China, the air temperature is often too high in summer, and the sunshine is also to strong, and the water is lost quickly, so for precious species, water praying should be done to decrease temperature after transplanted. If it is necessary, shading should be considered.Even though big tree transplantation is benefit for improving city's environment, technical difficulty and inputs should be considered. Taking actions that suit local circumstances should be advocated, but following other place with blindness should be prohibited. When transplanting, it is intolerance to destroy natural resource and environment.