毛竹冬笋Ca、Mg、Si含量动态变化及积累规律

冬笋是毛竹生长的第一阶段,其养分状况对毛竹林分产量和持续生产力具有重要影响。笔者选择安徽黄山地区毛竹,研究了该阶段Ca、Mg、Si 3种元素在冬笋中的含量变化及动态积累过程,结果表明:笋芽萌动后,随着冬笋生长和生物量增加,Ca和Mg在笋体内含量不断增大并迅速积累,而Si在冬笋生长中期有输出趋势; 至出土成为春笋前,Ca、Mg和Si的积累量分别达51.67、28.39、10.94 g/hm2。为准确掌握各生长阶段冬笋中Ca、Mg、Si 3元素的动态积累过程,采用多元线性逐步回归法,分别拟合了12月至次年3月单笋中3种元素积累量(Y, g)与笋高(H, cm)和笋径(d, cm)变化关系的模型,各模型相关系数均在0.85以上。
Winter shoot is the first growing period of Phyllostachys edulis, and its nutrition has significant effect on the output and continuous productivity of bamboo stand. P. edulis stand in Huangshan District of Anhui Province was chosen and tested. Ca, Mg and Si contents and their dynamic accumulation in winter shoots were studied in this paper. The results showed that Ca and Mg contents increased and accumulated rapidly in the shoots as growing after sprouting, but Si contents trended to decrease in mid-term. Before winter shoot pushed the soil up and became spring shoot, Ca, Mg and Si accumulation had reached 51.67, 28.39 and 10.94 g/hm2, respectively. In order to discover the rule of Ca, Mg and Si dynamic accumulation accutately, models of three elements accumulation(Y, g)to shoot height(H, cm)and diameter(d, cm)were established and tested with single winter shoot which was growing from December to March of the next year with multiple linear stepwise regression, and the correlation coefficient of each model was above 0.85