荷花(蓮) Nelumbo nucifera
(荷花，俗稱蓮Lotus)
…each leaf is studded with microscopic waxy bumps called papillae, just a hundredth of a millimeter high, as many as two million of them in an area the size of a thumbnail. The bumps make the surface hydrophobic by preventing water droplets from getting close enough to the body of the leaf to flatten and wet it—instead, surface tension causes rain to form globules that run easily downhill to the center of the leaf, where they combine to form a shimmering bead, leaving the leaf itself dry. A drier leaf is less prone to infection, but the papillae also keep the leaf’s surface spotlessly clean so that it can make the most of sunlight. Airborne dust, detritus and many fungal spores are sufficiently large that they settle on top of the papillae and are easily swept up by cascading rainwater droplets, which eventually roll off the swaying leaf…materials scientists have been inspired to mimic the ‘lotus effect’ , as it is known, to produce rainwear, window glass and paints that shrug off water and grime.
荷花很美，而它巨大的葉片能維持得那麼乾淨更是特別。
原來，荷葉表面廣佈只有百分之1微米(1萬奈米)高的乳突(papillae)狀蠟結構，水留不住也就不沾水。水有內聚力，形成水滴在荷葉上滾動，則會把荷葉上的灰塵帶走。現在終於知道為什麼它可以出污泥而不染了。
*：Jonathan Drori, “Around the world in 80 plants,“ 2021，Laurence King Publishing
P.S. 相片2025/6/16 攝於台南白河農地，海拔低於50公尺 。#荷花 #蓮
2025/11/9 荷花(蓮) Nelumbo nucifera Damakey
