南昌市不同植物类群叶片氮磷浓度及其化学计量比

对南昌大学前湖校区89种主要植物叶片的N、P浓度及其化学计量比进行了研究,结果表明:乔灌、常绿、针叶、种子、裸子和单子叶植物类群的N浓度分别低于相对应的草本、落叶、阔叶、蕨类、被子和双子叶植物类群,而C3和C4植物差异不显著;乔灌、常绿和裸子植物类群的P浓度含量分别低于相对应的草本、落叶和被子植物类群,而针叶和阔叶、蕨类和种子、单子叶和双子叶、C3和C4植物类群间差异不显著;乔木、阔叶、被子和双子叶植物类群叶片N/P分别高于相对应的灌草、针叶、裸子和单子叶植物类群,而常绿和落叶、蕨类和种子、C3和C4植物类群之间差异不显著.可见,不同类型植物对N和P的吸收利用存在差异,且对不同养分供应采取不同的适应对策.结合研究区土壤养分现状,建议优先选择常绿、针叶、裸子和单子叶植物类群作为城市园林植物.

Leaf N and P concentrations and their stoichiometric ratios of different functional groups of plants in Nanchang City

The study on the leaf N and P concentrations and their stoichiometric N/P ratios of 89 main plant species in the Qianhu Campus of Nanchang University showed that the leaf N concentrations of arbors and shrubs, evergreen trees, conifers, seed plants, gymnosperms, and monocotyledons were lower than those of herbages, deciduous trees, broadleaved trees, ferns, angio- sperms, and dicotyledons, leaf P concentrations of arbors and shrubs, evergreen trees, and gymnosperms were lower than those of herbages, deciduous trees, and angiosperms, and leaf N/P ratios of arbors, broadleaved trees, angiosperms, and dicotyledons were higher than those of shrubs and herbages, conifers, gymnosperms, and monocotyledons, respectively. No significant differences were observed in the leaf N concentrations between C3 and C4 plants, P concentrations between conifers and broadleaved trees, ferns and seed plants, monocotyledons and dicotyledons, and C3 and C4 plants, and N/P ratios between evergreen and deciduous trees, ferns and seed plants, and C3 and C4 plants. In a word, different functional groups of plants had different preferences for N and P, and their adaptation strategies to different soil N and P supplies were differed. Based on the soil nutrients status of study area, it was suggested that evergreen trees, conifers, gymnosperms, and monocotyledons could be preferentially selected as the urban garden plants in Nanchang City.