二球悬铃木三大裂片主脉夹角的实测与分析

 对505片二球悬铃木(Platanus acerifolia (Ait.) Willd.)叶片进行实测,发现两种新现象:一是二球悬铃木三大裂片主脉夹角含有"隐性"黄金数,即以三角函数形式显示的黄金数(0.618和0.382);二是二球悬铃木三大裂片主脉60.00°夹角是叶脉输导水分、养分走最短路径的表现,是一种斯坦纳树结构。统计分析表明,含有"隐性"黄金数的三大裂片主脉夹角(31.72°,38.18°,51.86°和67.55°)占总数的60.69%,呈斯坦纳树结构的60.00°夹角占总数的34.85%,二者合占95.54%。二球悬铃木三大裂片主脉夹角新现象的发现,有利于深化人们对植物结构的认识。

Actual Measurement and Analysis on Angles Between Principal Veins of Three Major Lobes of Platanus acerifolia (Ait.) Willd.

The 505 leaves collected with one leaf per plant from Platanus acerifolia (Ait.) Willd. were measured. Two new phenomena were found: Firstly, angles between principal veins of three major lobes from the plant indicated the "recessive" golden number". It was meant that golden number was showed by trigonometric function (values were -0.618 and 0.382); Secondly, angle of 60° between principal veins of three major lobes from the plant was a manifestation of taking the shortest path to transport moisture and nutrient, meanwhile this angle was a kind of the Steiner tree structure. Statistical analysis showed angles between principal veins of three major lobes of the plant containing recessive golden number were 31.72°, 38.18°, 51.86°and 67.55°, respectively. The amount of angles including 31.72°, 38.18°, 51.86° and 67.55°, were accounted for 60.69% of all collected leaves. And the percent of angle with 60° was 34.85% of all samples. Thus the amount of angles containing "recessive" golden number and presenting the Steiner tree structure was calculated for 95.54% in the whole samples. The new findings of angles between principal veins of three major lobes of P. acerifolia (Ait.) Willd. are very beneficial for people to deeply understandthe plant architecture.