Algal-fungal symbionts share water, nutrients, and gases via an architecture unique to lichens. Because lichen activity is controlled by moisture dynamics, understanding water transport is prerequisite to understand their fundamental biology. We propose a model of water distributions within foliose lichens governed by laws of fluid motion. Our model differentiates between water stored in symbionts, on extracellular surfaces, and in distinct morphological layers. We parameterize our model with hydraulic properties inverted from laboratory measurements of Flavoparmelia caperata and validate for wetting and drying. We ask: (1) Where is the bottleneck to water transport? (2) How do hydration and dehydration dynamics differ? and (3) What causes these differences? Resistance to vapor flow is concentrated at thallus surfaces and acts as the bottleneck for equilibrium, while internal resistances are small. The model captures hysteresis in hydration and desiccation, which are shown to be controlled by nonlinearities in hydraulic capacitance. Muting existing nonlinearities slowed drying and accelerated wetting, while exaggerating nonlinearities accelerated drying and slowed wetting. The hydraulic nonlinearity of F. caperata is considerable, which may reflect its preference for humid and stable environments. The model establishes the physical foundation for future investigations of transport of water, gas, and sugar between symbionts.

中文翻译：

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藻类-真菌地衣中的水和蒸汽传输：建模受实验室实验的限制，适用于Capelata Flavoparmelia。

藻类真菌共生体通过地衣独有的结构共享水，养分和气体。由于地衣的活动受水分动力学的控制，因此了解水的运输是了解其基本生物学的先决条件。我们提出了由流体运动定律控制的叶状地衣内水分布的模型。我们的模型区分了共生体，细胞外表面和不同形态层中存储的水。我们使用从Flavoparmelia caperata的实验室测量中得出的水力学特性对模型进行参数化，并进行润湿和干燥验证。我们问：（1）水运的瓶颈在哪里？（2）水合和脱水动力学有何不同？（3）造成这些差异的原因是什么？蒸气流的阻力集中在阀体表面，并充当平衡的瓶颈，而内部阻力较小。该模型捕获了水合和干燥中的磁滞现象，这些滞后现象显示出受液压电容非线性影响。消除现有的非线性会减慢干燥和加速润湿，而夸大的非线性会加速干燥和减慢润湿。F. caperata的水力非线性非常可观，这可能反映了其对潮湿和稳定环境的偏爱。该模型为将来研究共生体之间的水，气和糖的运输奠定了物理基础。而内部电阻很小。该模型捕获了水合和干燥中的磁滞现象，这些滞后现象显示出受液压电容非线性影响。消除现有的非线性会减慢干燥和加速润湿，而夸大的非线性会加速干燥和减慢润湿。F. caperata的水力非线性非常可观，这可能反映了其对潮湿和稳定环境的偏爱。该模型为将来研究共生体之间的水，气和糖的运输奠定了物理基础。而内部电阻很小。该模型捕获了水合和干燥中的磁滞现象，这些滞后现象显示出受液压电容非线性影响。消除现有的非线性会减慢干燥和加速润湿，而夸大的非线性会加速干燥和减慢润湿。F. caperata的水力非线性非常可观，这可能反映了其对潮湿和稳定环境的偏爱。该模型为将来研究共生体之间的水，气和糖的运输奠定了物理基础。同时夸大非线性会加速干燥并减慢润湿。F. caperata的水力非线性非常可观，这可能反映了其对潮湿和稳定环境的偏爱。该模型为将来研究共生体之间的水，气和糖的运输奠定了物理基础。同时夸大非线性会加速干燥并减慢润湿。F. caperata的水力非线性非常可观，这可能反映了其对潮湿和稳定环境的偏爱。该模型为将来研究共生体之间的水，气和糖的运输奠定了物理基础。