武汉植物园21种迁地保护珍稀植物大量营养元素质量分数和吸收系数

在“生态相似性”营养保育策略的指导下,研究了武汉植物园迁地保护的樟科Lauraceae和木兰科Magnoliaceae 21种珍稀植物的营养状况,以及它们所生长土壤的营养条件。结果表明,土壤大量元素平均质量分数顺序为钙>镁>氮>钾>硫>磷。质量分数和元素顺序说明可供植物吸收利用的氮磷钾较为缺乏。元素平均值、背景值以及氮、磷比值分析可以得出,植物体内的磷、硫以及氮较为缺乏。6种元素的生物吸收系数顺序为氮>磷>钾>硫>钙>镁,这在一定程度上反映植物对6种元素的需求顺序。针对21种植物叶片营养状况与土壤营养条件的关系,为确保珍稀植物“从种子到种子”的成功,建议适量增加土壤中可供植物吸收利用的氮、磷和钾。图1表6参17

Mass fraction and bioavailability of macronutrients of 21 ex-situ conservation rare plants in Wuhan Botanical Garden

Based upon the plant nutrient conservation strategy "ecogical similarity"of ex-situ conservation,the nutrient status and the soil condition of 21 kinds of ex-situ conservation rare plants of Magnoliaceae and Lauraceae in Wuhan Botanical Garden were studied.The results showed that the sequence of average content of macronutrients in the soil was Ca>Mg>N>K>S>P.The sequence and the average content of macronutrients indicated that the contents of available nitrogen,phosphor and potassium were low in the soil.And through the analysis of the average contents,background content and the ratio of N/P,it was found that the contents of phosphorus,sulphur and nitrogen were low in the plant leaves too.The bioavailability sequence of the 6 elements was N>P>K>S>Ca>Mg,which could reflect the damand sequence of plant in some way.Based upon the analysis of the nutrient status of plant leaves and soil,it was suggested that more N,P and K should be added inthe soil to assure the success growth of rare plant "from seed to seed".