室内模拟波浪对2种典型滨海湿地挺水植物生物力学特征的影响

选取本地物种芦苇和入侵物种互花米草为研究对象，利用波浪装置对生长期的植物进行波浪处理后对其形态特征，根、茎、叶的拉力、弯曲特性进行研究，以探讨湿地植物对波浪作用的生物力学响应。结果表明，芦苇、互花米草经波浪处理后的茎直径均显著高于对照组（P=0.008，P=0.03）；互花米草总体呈现拉力或者弯曲载荷高于芦苇的现象（如茎秆），但应力（根系）或静曲强度（茎秆）却要低于芦苇，即对应了互花米草比芦苇茎秆更粗壮的现象，但芦苇自身的强度会更强，其木质素和纤维素的结构成分显示出显著高于互花米草的现象（P<0.001，P<0.001）。总体来看，通过短时间的波浪模拟，植株在形态特征上发生了显著的变化，而植物自身的生物力学特性与形态、结构成分都息息相关。研究结果对于评价芦苇和互花米草在应对海浪影响的潜力、从植物生物力学角度探究滨海湿地的保护和修复都提供了一定的参考。

Effects of the simulated wave on the biomechanical characteristics of two typical coastal wetland plants

Typical local species Phragmites australis and invasive species Spartina alterniflora are selected in this study. We quantify how their morphological properties and the biomechanical properties of root, stem and leaves are affected by wave exposure during the growing seasons. Results show that the stem diameter of both P. australis and S. alterniflora growing with the wave is significantly higher than that of the control group (P=0.008,P=0.03). S. alterniflora shows a higher tensile or bending force than that of P. australis while the stress or static bending strength is lower. The higher equivalent stress contributes to the rigidity of P. australis although S. alterniflora owns a thicker individual. Furthermore, lignin and cellulose of P. australis are higher than that of S. alterniflora (P<0.001). Overall, plants have undergone significant changes in morphological characteristics, and the biomechanical characteristics of plants are closely related to structural compounds. The results assess the potential of plants in coping with the impact of waves, as well as provide a case in plant biomechanical study in coastal wetland protection and restoration research.