关键词: 水竹, 开花, 更新试验, 地下茎, 碳氮代谢, 森林转换, 天然林, 人工林, 土壤CO₂排放, 水溶性有机碳

Abstract: In order to search for the ways to restrain the flowering process and promote the regeneration of bamboo (Phyllostachys heteroclada), five types of regeneration experiments were conducted, including 1) harvesting all the bamboos in the first year and the flowered bamboos in the next year all at the beginning stage of florescence, 2) harvesting the flowered bamboos at the beginning stage of florescence in two consecutive years, 3) harvesting the fully flowered bamboos in the first year and the bamboos at the beginning stage of florescence in the next year, 4) fertilizing the bamboo floor before growing season in consecutive two years, and 5) no any manipulation. In each of the cases, the carbon- and nitrogen metabolism and related enzyme activities in bamboo rhizome were studied. The results showed that treatment 1 had the best effect, which resulted in the greatest number (207) of new shoots produced and with the highest survival rate (69.33%), and had the most obvious effect on restraining bamboo flowering and promoting regeneration. Also, it produced the highest contents of soluble sugar (10.89%) and total sugar (20.39%), the highest total sugar to total nitrogen ratio (34.56), and the highest glutamine synthetase activity (104.52 mg·g^-1·h^-1) in bamboo rhizome. These findings demonstrated that the carbon- and nitrogen metabolism in the rhizome had definite relationships with the flowering process and regeneration of bamboo, and the rhizome growth played a critical role in bamboo propagation.

Key words: Phyllostachys heteroclada, flowering, regeneration experiment, rhizome, carbon-and nitrogen metabolism, forest conversion, natural forest, plantation forest, soil CO₂ flux, water soluble organic carbon.