植物生态学报 ›› 2007, Vol. 31 ›› Issue (4): 665-672.DOI: 10.17521/cjpe.2007.0086

• 论文 • 上一篇    下一篇

底泥高磷浓度提高了喜旱莲子草的入侵性

申瑞玲1,2, 关保华1,2, 蔡颖1,2, 安树青1,2,*(), 蒋金辉1,2, 董蕾3   

  1. 1 污染控制和资源化研究国家重点实验室, 南京大学生命科学学院, 南京 210093
    2 南京大学湿地生态研究所, 南京 210093
    3 中国科学院华南植物园,广州 510650
  • 收稿日期:2006-07-19 接受日期:2007-01-05 出版日期:2007-07-19 发布日期:2007-07-30
  • 通讯作者: 安树青
  • 作者简介:* E-mail: anshq@nju.edu.cn
  • 基金资助:
    科技部镇江863专项(2003AA06011000-04);科技部太湖863专项(2002AA601012-06)

HIGH SEDIMENT PHOSPHORUS CONCENTRATION ENHANCED INVASIVENESS OF ALTERNANTHERA PHILOXEROIDES

SHEN Rui-Ling1,2, GUAN Bao-Hua1,2, CAI Ying1,2, AN Shu-Qing1,2,*(), JIANG Jin-Hui1,2, DONG Lei3   

  1. 1The State Key Laboratory of Pollution Control and Resource Reuse, School of Life Sciences, Nanjing University, Nanjing 210093, China
    2Institute of Wetland Ecology, Nanjing University, Nanjing 210093, China
    3South China Botanical Garden, Chinese Academy of Sciences, Guangzhou 510650, China
  • Received:2006-07-19 Accepted:2007-01-05 Online:2007-07-19 Published:2007-07-30
  • Contact: AN Shu-Qing

摘要:

植物通过改变自身的形态和生态生理特征对多变的环境因素做出响应,这种表型可塑性能增强外来物种的入侵能力。该文研究了入侵植物喜旱莲子草(Alternanthera philoxeroides)对底泥磷浓度、植株密度以及二者间交互作用的可塑性响应,探讨可塑性是否能使其获得更高的入侵能力。结果表明:低密度×底泥高磷浓度处理条件下的叶重、茎重、总重、叶数、分枝数和茎长等明显高于低、中磷浓度处理;高密度×底泥高磷浓度条件下的叶数、茎长和比茎长的值最大;植株的含磷量随底泥磷浓度的升高显著增加,说明喜旱莲子草响应底泥磷浓度变化时改变了自身的形态与生态生理性状。泥底含磷量对叶重比、叶数、茎长、茎磷含量、叶磷含量和植株总含磷量的影响都达到显著水平(p<0.05);植株密度对茎重、比茎长、叶磷含量和植株总磷含量的影响达到显著水平(p<0.05)。与入侵能力相关的叶重比、叶数、茎长在底泥高磷浓度处理中显著增加,说明底泥的高磷浓度增强了喜旱莲子草的入侵能力。

关键词: 表型可塑性, 底泥磷浓度, 植株密度, 入侵性, 克隆生长, 喜旱莲子草

Abstract:

Aims Plants show phenotypic plasticity in response to changing environments via variations of morphological and ecophysiological traits, and this plasticity can increase invasiveness. Plasticity, rather than genetic diversity, made Alternanthera philoxeroides more invasive, but its plasticity to sediment phosphorus concentration of invaded habitats was undocumented. This study addresses plasticity of A. philoxeroides to sediment phosphorus concentration and planting density and whether plasticity increases invasiveness.
Methods In a controlled factorial experiment, we grew artificial populations of A. philoxeroides at low and high densities (four and eight individuals per container, respectively) under three levels (low, median, high) of sediment phosphorus concentrations. All plants were harvested after six weeks, and dry mass of leaves, stems and roots were measured.
Important findings Under low planting density, leaf mass and number, stem mass and length, branch number, and total biomass of A. philoxeroides were larger at high than low or median sediment phosphorus concentration. Under high planting density, leaf number, stem length and special stem length were greater at high than at low or median sediment phosphorus concentration. Leaf, stem, root and total phosphorus concentrations in A. philoxeroides increased significantly with increasing the sediment phosphorus concentration. Leaf mass ratio was also affected by sediment phosphorus concentration, and stem mass, special stem length, leaf and total phosphorus concentration were significantly affected by planting density. Results imply that morphological and ecophysiological traits of A. philoxeroides were altered by sediment phosphorus concentration and that high sediment phosphorus may strengthen the invasiveness of A. philoxeroides.

Key words: phenotypic plasticity, sediment phosphorus, planting density, invasiveness, clonal growth, Alternanthera philoxeroides