| Phyllostachys pubescens is widely used in many aspects and easy to cultivate. It has short growth cycle, high economic value and ecological benefits. So it is an urgent need to enhance the productivity and to expand the cultivation of bamboo forest area. Cultivating seedling planted bamboo is an effective means to expand bamboo cultivation area.This paper took bamboo forest which is in the district of Huangshan in Anhui Province without human disturbance as the research object, making research on dynamic changes of chemical properties and enzyme activities of rhizosphere soil at different growth stages of bamboo, aiming at providing theoretical basis for precise fertilization in root region of bamboo, and improving fertilizer efficiency. At the same time, we made an analysis about the effects of fertilization on bamboo seedlings, and established the DRIS nutritional diagnosis to provide theoretical basis for the management of seedling bamboo nutrition. The main conclusions are as follows:1. The changes of soil chemical properties and enzyme activities were different in rhizosphere soil of Moso bamboo at different growth period. Contents of organic matter,total nitrogen, available nitrogen, total phosphorus, activities of phosphatase and protease increased with time. While pH, available phosphorus, available Fe, available Mn, invertase and catalase decreased and then increased with the growth of Moso bamboo. During the whole growth period of Moso bamboo, available potassinum was decreasing, the change of available Zn was not evident, and the change of total potassinum and urease were relatively steady.2.The comprehensive factor scores of rhizosphere soil of Moso bamboo at different growth period were in the order of growth period >â…£du>â…¢du>â…¡du >â… du. The scores are 1.0741,1.0201,0.9856,0.9652,0.065 respectively. It is clear that the soil quality was increasing after decreasing. At growth period of Moso bamboo, because the root has not grown completely and has little influence on rhizosphere soil, so the score was the highest. The score of rhizosphere soil decreases as the growth and root gradual development of Moso bamboo. The rhizosphere soil quality increased at later stage of Moso bamboo because of gradually weakened growth and the increased litter and microorganism activity.3.The demands for nutrients of Moso bamboo at different growth periods were different. It was different in the demand for nutrients of Moso bamboo at different growth period. The results showed that the nutrient contents of different organs at growth stage were higher than those at other stages. Regression analysis showed that the organ biomass was significantly correlated to macroelement, soil enzymes and organic matter at the different growth stages of Moso bamboo.4.Different fertilizers had different effects on the growth characteristics of Moso bamboo seedlings. When the fertilization of phosphorus and nitrogen are both 0.3g per plant, the heights of Moso bamboo seedlings were the highest, 13.2cm and 10.5cm in average, respectively. After nitrogen fertilizer was applied, the phosphorus content in Moso bamboo seedlings increased, while nitrogen, potassium, Cu, Fe and Mn contents in Moso bamboo seedlings decreased after phosphorus was applied, the elements of nitrogen and phosphorus increase, potassium decreases, Cu and Fe increased after the first drop, Zn increases, Mn inreased and then decreased. After potassium was applied, the height of Moso bamboo seedlings was the highest, averaging 10.8 cm at 0.2g/plant; the organ biomass of Moso bamboo seedlings was the highest, averaging 1.48 g at 0.3g/plant; and the contents of nitrogen and potassium increased, phosphorus, Cu, Fe, Zn and Mn decreased. Formula fertilization, more nitrogen fertilization, proper amount of phosphorus fertilization and less potassium fertilization can increased the height of Moso bamboo seedlings. The changes of organ biomass were not obvious at all treatments when fertilizer phosphorus. Application of 0.1g nitrogen plus 0.4g phosphorus per plant, or 0.2g nitrogen plus 0.1g phosphorus and 0.3g potassium per plant could promote the absorption of nutrient of bamboo seedlings. DRIS nutrition diagnosis results showed that the fertilizer application standard is N/P=14.0718,P/K=0.1632,N/K=2.2518.5.Fertilization had significant effect on the photosynthetic characteristics of Moso bamboo. Application of nitrogenous fertilizer increased the maximum net photosynthetic rate, intercellular CO2 concentration, and stomatal conductance of bamboo seedlings, reduced the CO2 compensation point and light compensation point, and increased solar energy utilization and chlorophyll content. After application of K fertilizer, the net photosynthetic rate increases and then decreases and becomes stable; stomatal conductance, transpiration rate and the maximum net photosynthetic rate had the similar trend of decline; intercellular CO2 concentration, CO2 compensation point and light compensation points are increasing, but CO2 and light energy utilization rate were reducing. Chlorophyll content did not change significantly. Applying P fertilizer the maximum net photosynthetic rate, stomatal conductance, transpiration rate increased after the decreasing in the beginning, CO2 compensation point and light compensation point increase, while chlorophyll content did not change significantly. Formula Fertilization, except that the combination of small amount of N with appropriate P and K can increase photosynthetic characteristics, the rest do not have significant effects.
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