甘肃民乐东灰山遗址炭化小麦籽粒性状分析

Study on the Kernel Properties of Carbonized Wheat in Donghui Hill of Minle in Gansu Province

甘肃省民乐县东灰山遗址炭化小麦(Triticum aestivum)的发现和研究在中华民族的农业发展史、饮食文化史、东西交流史及"丝绸之路"历史中具有重要的地位,对认识近百年来小麦品种改良和进化过程具有重要意义。本研究通过遗址地土壤样本浮选方法获得碳化植物样本。经对小麦籽粒样本的分离鉴定、成分分析和资料比对,形成如下初步结果:(1)东灰山炭化小麦单籽粒均重为9.52 mg,变化范围为3.01～17.40mg,变异系数较大(30.56%)。单籽粒平均长度为4.62mm,平均宽度为3.26mm;籽粒宽/长比例均值为0.71,变化范围为0.56～0.91。炭化小麦长度比现代小麦品种(永宁15号)籽粒短(0.83∶1.00),宽度基本一致(0.99∶1.00)。推算当时小麦的实际单粒重量为现代小麦重量的45%～47%。(2)东灰山炭化小麦籽粒的同位素^(15)N含量较高,说明当时人们主要依靠自然肥力或使用农家肥栽培小麦。(3)东灰山炭化小麦籽粒的主要矿物元素铅、锶、铜、锌含量很高,提示当时小麦生产环境与人类活动或青铜器冶炼有某种联系。(4)东灰山炭化小麦籽粒年代的确定和传播路径分析,为小麦从4 000年前起通过祁连山扁都山口逐步传入青海海东和甘肃临夏地区,再进入关中地区提供了佐证。(5)在东灰山遗址炭化植物残留中首次鉴别出了荞麦籽粒(Fagopyrum esculentum)和燕麦籽粒(Avena sativa)。

Discovering and studying kernel properties of carbonized wheat(Triticum aestivum)in Donghui Hill ruins of Minle county,Gansu province,China,plays an important role in history of Chinese agricultural development,of diet culture,of exchange between East and West,as well as in history of“Silk Road”,which affords us significant reference that merit attention in progress of improving and evolution of wheat variety in last hundred years in China.We obtained carbonized plant samples through flotation techniques of soil samples from Donghui Hill.After the isolation and identification,component analysis,and reference review,preliminary results were as follows:(1)The average single kernel weight of carbonized wheat kernel is 9.52 mg,ranging from 3.01 mg to 17.40 mg,with higher coefficient of variation(CV).The average length and width of kernel is 4.62 mm and 3.26 mm,respectively.The ratio of kernel width to length kernel is 0.71,ranging from 0.56 to 0.91.The kernel length of carbonized wheat is shorter than that of modern wheat variety Yongning 15(0.83∶1.00),but they have similar kernel width.It is speculated that the single kernel weight of Donghui Hill is 45%to 47%of that in modern wheat(Yongning 15).(2)The higher isotope 15 N content in carbonized wheat kernel indicated that the farming relied mainly on natural fertility,or using organic farmyard manure for wheat cultivation.(3)Major minerals are high in zinc(Zn),copper(Cu),lead(Pb),and strontium(Si),which prompted there was some connection between wheat production environments and human activities or bronze smelting.(4)Ascertaining the cultivation years of carbonized wheat in Donghui Hills,and analyzing spread way from western to eastern of wheat,provided historic evidence how to spread the wheat from the Donghui Hill to East region of Qinghai and Linxia region of Gansu through the Biandoukou in Qilian mountains,and even continually to middle China since 4 000 years ago.(5)This study also identified for the first time buckwheat(Fagopyrum esculentum)and oat kernel(Avena sativa)in this ruins.