Interaction between the Jomon Farmer and the Yayoi Farmer in the Beginning of the Yayoi Period along the Old Kawachi Lake（Part 3 Research on Contiguous Territories in the Ancient Period）

本稿は，水田稲作が大阪平野でどのように始まったのか，そのプロセスやメカニズムを，ヨーロッパ先史考古学のフロンティア理論を用いて考えたものである。30年ほど前からこの地域における水田稲作の開始問題を論ずる場合には二つの大きな考え方があった。一つは本地域の西方から水田稲作民がやってきて入植し，もともと住んでいた在来の採集狩猟民である近畿縄文人と共存して，その中で交流が始まって水田稲作が広まったという「移住説・外来説」「住み分け説」と，近畿縄文人が水田稲作の技術を受け入れて，農耕民に転換していったという「自生説」である。この二つの解釈の根拠は，地元の人びとが使うと仮定された縄文系土器と，西方からやって来た人びとが使うと仮定された遠賀川系土器との関係にある。すなわち両者が同時に存在していたのか，それとも時期差なのかという点である。大阪平野では二つの土器群が確実に共伴する遺構がほとんど知られていないので，これまで同時存在なのか時期差なのか決め手に欠ける状況が続いていた。本稿では，二つの土器群に付着する炭化物の炭素14年代値をもとに算出した土器群の較正暦年代を使って比較したところ，二つの土器群の一部が同時に存在していたことがわかった。その期間は100～150年にも達する。しかもこの期間の水田は定型化した灌漑施設をもつものではなく，土器自体も弥生土器として定型化する前の段階にあたることから，縄文社会が水田稲作を始めてから弥生社会へと転換するための準備期間に相当し，定型化するまで100～150年を要したことを意味している。このように縄文文化的な特徴が色濃く残る大阪平野の弥生Ⅰ期前葉は，少数のニューカマーと多数のネイティブとの接触交流によって，ニューカマーのもつ文化に100年以上かかって地域全体が統合されていくというフロンティア理論に近いことがわかった。水田稲作が始まるやいなやきわめて短期間のうちにコメの生産量を増大し，社会が急速に発展したという従来の説明とはほど遠い状況だったことを明らかにした。

This paper considers the process and mechanism by which wet rice cultivation began in the Osaka Plain, using the Frontier Theory from European prehistoric archaeology. For about the past 30 years or so there have been two broad approaches when discussing the question of the beginning of wet rice cultivation in this region. According to one, rice farmers from further west of the region came and settled, and interaction began while coexisting with the Kinki Jomon man hunters and gatherers who had already lived there for some time, resulting in the spread of wet rice cultivation. These are the“migration and outsider”and“segregation”theories. Then there is the“indigenous”theory, according to which Kinki Jomon people obtained wet rice cultivation technology and became farmers. The basis for these two interpretations is the relationship between Jomon implements presumed to have been used by native inhabitants and the Onga River implements presumed to have been used by people from the west. That is to say, these interpretations are based on whether both existed simultaneously or whether there was a time interval. Since there are virtually no known archaeological sites in the Osaka Plain where these two groups of implements have definitely been found together, so far a decisive factor with the potential to determine either simultaneous coexistence or a time interval has been lacking.In the study described here, a comparison using the calibrated calendar years for the groups of implements calculated based on C14 values of carbonized materials adhering to the two types of implements revealed that some items in both groups existed at the same time. This period extends for as long as 100 to 150 years. What is more, rice paddies at this time did not have standardized irrigation systems and the implements themselves belong to the stage prior to the standardization of Yayoi implements. Consequently, this represents a preparation period for Jomon society to make the switch to Yayoi society after they had started cultivating rice, which means that standardization required a period of 100 to 150 years.As a result of interaction between a small number of newcomers and a large number of natives in the Osaka Plain in the beginning of the Yayoi period when characteristics of Jomon culture were still much in evidence, the culture of the newcomers took more than 100 years to become integrated across the entire region. This is similar to Frontier Theory. In conclusion, the study shows that the situation was a far cry from the conventional explanation that society developed rapidly due to the increase in the volume rice production in an extremely short time after it began.

source:https://www.rekihaku.ac.jp/outline/publication/ronbun/ronbun7/index.html#no152