Positive Study on the Presence of Rice Cultivation before the Beginning of Rice Cultivation in Paddy Fields

对陶片中的植物蛋白石进行检测，是证明在陶器制作之前，提供所检测的植物蛋白石的植物的存在的有效方法之一。本研究对水稻栽培时期进行了研究。和其他谷物作物开始在日本种植。研究结果总结如下：1.研究成果。通过对鹿儿岛县上野原遗址(Echinochloa crus-Galli Beauv.)植物蛋白石是从大约公元前9000年左右积累起来的苔藓土层下面的土层中发现的。藜草和日本小米是可食用的，关系密切。因此，这些结果表明，日本谷子的原始栽培可能开始于日月时代的早期。2.日月时代早期的情况在青森县三生丸遗址的陶片中发现了大量的藜草植物蛋白石。考虑到该遗址的规模和性质，可能进行了日本谷子的种植。3.从冈山大学校舍遗址(冈山县)和南水町遗址(冈山县)出土的陶器中发现了日本小米末期水稻植株蛋白石的情况。据估计，这些陶器制作于公元前3500年左右。这一结果表明，这一时期日本西部地区已经开始种植水稻。通过对长崎县平部县的调查，在公元前360年左右Mutsuki火山碎屑流积累的火山灰下的土层中发现了水稻植物蛋白石。考虑到该地点的位置和其他植物遗骸的存在，这里的水稻种植可能是在旱地进行的。

To detect plant opals contained in pottery sherds is one of effective methods to prove the existence of plants which supplied the detected plant opals before the period when the potteries were made. In this study, it is examined about the period the cultivation of rice (Oryza sativa L.) and other Gramineae crops began in Japan. The result is summarized as follows.1. The situation in the early stage of Jyomon periodAs a result of the investigation in Uenohara site (Kagoshima prefecture), Barnyard grass (Echinochloa crus-galli Beauv.) plant opals are detected from the soil layer just under the tephra layer which was accumulated around 9000 B.C.. Barnyard grass and Japanese millet are edible and closely related. So, these results suggest the possibility that the primitive cultivation of Japanese millet had begun in the early stage of Jyomon period.2.The situation in the early Jyomon periodA lot of Barnyard grass plant opals were detected in pottery sherds which derived from Sannaimaruyama site (Aomori prefecture). Considering the scale and the character of this site, there may be possibility that the cultivation of Japanese millet was done.3 .The situation in the last part of Jyomon periodRice plant opals were detected from pottery excavated from Okayama University premise site (Okayama prefecture) and Minamimizote site (Okayama prefecture). These potteries are estimated to have been made around 3500 B.P.. This result shows that rice cultivation already had begun in the western part of Japan in this period.And as a result of the investigation in Hietabaru site (Nagasaki prefecture), rice plant opals were detected from the soil layer just under the volcanic ash layer which was accumulated by Mutsuki pyroclastic flow glad around 3600 B.P..Considering the location of this site and the existence of other plant's remains, rice growing here possibly had been done at upland fields.