The dispersal of winged fruits and seeds differing in autorotative behaviour
The dispersal of winged fruits and seeds differing in autorotative behaviour
复制标题
有翅果实和种子的传播具有不同的自转行为
作者：
D. Greene;E. Johnson
将重粒子扩散的微气象模型应用于有翼水硬铝石（翅果），要求水硬铝石保持稳定的飞行，并且下降速度相对于垂直空气运动是恒定的。其他人则认为，这些假设对于自转翅片可能无效，并且在大水平风速（和（或）高湍流）的条件下，双边对称翅片会比不对称翅片分散得更远，因为不对称形态本质上在飞行中不太稳定。因此，这些模型的应用可能不适用于不对称翅果。这里报道的不对称和对称翅片的实验和自然释放表明，两种翅片形态对给定流态的响应相似。因此，在模拟扩散时，可以忽略翅片的自转，并且可以将翅片视为以恒定速率从源到沉积点下降的重粒子。关键词：带翅种子、后裔...
The application of micrometeorological models of heavy particle dispersal to winged diaspores (samaras) requires that the diaspores maintain stable flight and that descent velocity is constant with respect to vertical air motion. Others have argued that these assumptions may be invalid for autorotating samaras and that bilaterally symmetric samaras will disperse farther than asymmetric samaras in conditions of large horizontal wind velocities (and (or) high turbulence) because the asymmetric morphology is inherently less stable in flight. Therefore, application of these models may not be appropriate for asymmetric samaras. Experimental and natural releases of asymmetric and symmetric samaras reported here indicate that the two samara morphologies respond similarly to a given flow regime. Thus, in modelling dispersal, the autorotation of the samaras can be ignored, and the samaras can be regarded as heavy particles descending at a constant rate from source to deposition site. Key words: winged seeds, desce...