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Expressway central median survival rate of green plants in China has been low, which with its harsh arid site conditions are inseparable, according to the characteristics of micro-climate, selection of drought-resistant plants are greening the key to success. Thesis Gallery Zhuo highway guardrail central New Jersey medians as the research object, a qualitative analysis of the characteristics of its site soil and climatic conditions, and drought resistance, through the analysis of plant physiology, growth indicators, evaluation of different plant Drought, select central median growth of plants, the thesis results show that: (1) Gallery Zhuo highway median strip of soil nutrients and soil aggregates content and more serious, particularly in the absence of P fertilizer, low content of soil aggregates, soil poor water stability, soil moisture is easily lost. Also there is cold and dry in winter and spring, high winds and little rain, the phenomenon of high temperature and drought in the summer and autumn, and the most serious spring drought, soil water content was only 6% in March and April, below the plant wilting coefficient, these factors threatening the plant The survival of growth. (2) under the potted water stress conditions, the the five plant's net photosynthetic rate (Pn), transpiration rate (Tr) and stomatal conductance (Gs) with drought stress aggravated gradually decreased, but the five kinds of changes under different water conditions show certain differences, reflecting the capacity of different plants to drought, which Euonymus (Buxus megistophylla) when soil moisture content is 60% to 65% under the conditions that interference by drought conditions in 40% to 45% water stress threshold has been reached; Purple Leaf Barberry (Berberis thumbergii) and rose (Rosa hybrida) relative water content in the soil disturbed under the conditions of 60% to 65%, 20% -25% to reach the water stress threshold; side cypress (Platycladus orientalis) and lobular boxwood (Buxus sinica) drought resistance, only disturbed soil relative water content of 20% -25% the moisture threshold required further study. (3) field tests of five plant photosynthetic parameters measured with potting soil relative water content of 40% ~ 45% (W2) is closer to the test results, the photosynthetic rate roughly the same value, but by the field of light, air humidity and wind speed factor impact to the transpiration rate, stomatal conductance is relatively low, the plants in order to reduce the loss of water in the arid environment; survival data by using the the photosynthetic parameter data of the field and pot, as well as the wild growth, drought resistance of five plant objective evaluation, the evaluation results: oriental arborvitae (0.84) gt; Buxus microphylla (0.45) gt; Rose (0.44) gt; Purple Leaf Barberry (0.28) gt; Euonymus this initial choice of arborvitae, Buxus microphylla (0.05); The appropriate central median planting plants and Rose.
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