Sessile organisms such as macroalgae located in the intertidal and shallow subtidal zones are subject to a hydrodynamically diverse environment, controlling the variation of intraspecific morphology and distribution. Kelp forests experience both waves and/or currents, yet, how kelp blade material mechanically differs between these various hydrodynamic environments and what drives the variation in strength and extensibility are not fully understood. Here, the mechanical properties, cellular composition and blade tissue thickness of the meristematic region and distal tips of the kelp Laminaria digitata blades were quantified and compared between seasons and among three hydrodynamic environments: wave dominated, current dominated and a benign hydrodynamic environment. Kelps associated with energetic environments, generally tended to be stronger yet more extensible than those growing in the benign hydrodynamic environment. Higher extensibility was located at the meristematic region whereas tissue was stronger in the distal tip of the blade. Linking both cellular composition and mechanical properties, results suggest enhancement of medulla cells in the meristematic region increases extensibility, potentially protecting the thallus during increased storm activity while growing in a wave/current exposed habitat. Investment in cortex cells towards the tip of the blade suggests an increase in strength of the region, which is susceptible to breakage. However, the lack of variation in the proportion of medulla and cortex cellular layers between distinct hydrodynamic environments revealed that the potential overall strategy for avoiding breakage in energetic hydrodynamic environments is that of investing energy into the increased thickness of blade tissue.

位于潮间带和浅潮下带的固着生物（例如大型藻类）受到水动力多样化环境的影响，控制着种内形态和分布的变化。海带森林会经历波浪和/或水流，然而，海带叶片材料在这些不同的水动力环境之间的机械差异以及驱动强度和延展性变化的因素尚不完全清楚。在这里，对海带海带叶片分生组织区域和远端尖端的机械特性、细胞组成和叶片组织厚度进行了量化，并在季节之间和三种水动力环境（波浪主导、水流主导和良性水动力环境）之间进行了比较。与充满活力的环境相关的海带通常比在良性水动力环境中生长的海带更坚固且更具延展性。较高的延伸性位于分生组织区域，而组织在刀片的远端尖端更强。将细胞组成和机械性能联系起来，结果表明，分生组织区域髓质细胞的增强增加了延伸性，可能在风暴活动增加期间保护叶状体，同时在波浪/洋流暴露的栖息地中生长。朝向刀片尖端的皮层细胞的分布表明该区域的强度增加，该区域容易断裂。然而，不同的水动力环境之间髓质和皮层细胞层的比例缺乏变化表明，避免在高能水动力环境中断裂的潜在总体策略是将能量投入到增加的叶片组织厚度中。