Willby N J, Pulford I D, Flowers T H
Department of Environmental & Evolutionary Biology, University of Glasgow, Glasgow G12 8QQ, Scotland.
Present address: Department of Environmental Science, University of Stirling, Stirling, FK9 4LA, UK.
New Phytol. 2001 Dec;152(3):463-481. doi: 10.1046/j.0028-646X.2001.00274.x.
• An extensive survey of European wetlands was undertaken to compare the importance of growing conditions vs functional characteristics of vegetation in determining N, P and K contents. • Stress-tolerator dominated stands (S) had consistently lower nutrient contents and higher N : P ratios whereas ruderal-dominated (R) stands displayed the opposite pattern. Competitor (C) and competitor-stress tolerator (CS) stands were intermediate to R and S. • These patterns were mostly preserved after removing covariation between vegetation and environment, thus indicating constitutional differences in nutrient signatures between functionally differentiated vegetation. C and R stands were least likely to be nutrient limited. Half of the S stands were probably P-limited but C, CS and R stands rarely or never experienced P limitation. Inferred colimitation by K was twice as frequent in S stands compared with other vegetation. • This study extends the evidence for syndromes of traits closely linked to nutrient use efficiency that increase fitness under particular growing conditions. It also highlights patterns at a community level across a wide range of wetland types and suggests that tissue nutrient signatures will have diagnostic value in predicting community responses to perturbation in nutrient availability.
• 开展了一项针对欧洲湿地的广泛调查,以比较生长条件与植被功能特征在决定氮、磷和钾含量方面的重要性。
• 以耐胁迫植物为主的群落(S)的养分含量始终较低,氮磷比更高,而以杂草为主的群落(R)则呈现相反的模式。以竞争植物为主的群落(C)和竞争-耐胁迫植物群落(CS)处于R和S之间。
• 在消除植被与环境之间的协变关系后,这些模式大多得以保留,这表明功能分化的植被在养分特征上存在本质差异。C和R群落最不容易受到养分限制。一半的S群落可能受到磷限制,但C、CS和R群落很少或从未经历过磷限制。与其他植被相比,S群落中钾的推断共同限制频率是其他植被的两倍。
• 本研究扩展了与养分利用效率密切相关的性状综合征的证据,这些性状在特定生长条件下可提高适应性。它还突出了广泛湿地类型在群落水平上的模式,并表明组织养分特征在预测群落对养分有效性扰动的反应方面具有诊断价值。