奈良盆地弥生式遺跡における花粉分析学的考察

DOI Web Site 被引用文献1件

書誌事項

タイトル別名
  • PALYNOLOGICAL STUDY OF YAYOI SITES IN NARA BASIN
  • ナラ ボンチ ヤヨイシキ イセキ ニ オケル カフン ブンセキガクテキ コウサツ

この論文をさがす

抄録

The purpose of this paper is to reconstruct the vegetation in the Yayoi sites of Nara Basin by pollen analysis, as an approach to the subject in what landscape rice cultivation was adopted in Japan.<br> The relation between plant relics excavated from the sites and warmth index was used as a clue to the reconstruction of the climate in the Yayoi era. Oak, passania and camphor trees range 180-185°C of warmth index and-10_??_-15°C of cold index. Camphor trees, above all, are distributed between 120°C and 180°C of warmth index, while the warmth index of the present Shizuoka city, which is close to Toro, Shiroiwa and Yamagi sites where camphor relics were excavated, is 127.7°C (average temperature of the year-15.6°C) . Therefore, even on the supposition that the climate of those days was cooler than that of today, we could not assume a climate cooler than that of the present Nagoya and its neighborhood (warmth index-118. 8°C, average temperature-14. 4°C) . In other words, while the studies of cli-matic change made in Japan have assumed a cool climate in the Yayoi era, it is noteworthy that even camphor trees should have grown in Tokai region. However, the present writer observed that fragments of the Yayoi pottery were dug up from the layer of peaty clay in Nara Basin. This fact indicates that the peaty clay was formed under the cool climate of the Yayoi era.<br> The pollen analysis, in which the clay or the peaty clay taken from Yayoi layers in Nara Basin, gave the following results.<br> (1) Arboreal Pollen (AP)<br> Quercus and Pinus are found to be predominant. It would be possible to identify the former with evergreen Quercus such as Quercus glauca, Quercus acuta and Quercus gilva, all of which were unearthed as botanical remains. The Pinus pollen, on the other hand, is regarded as consisting of that of Pinus densiflora or Pinus thurbergii. Of the broad-leaved trees except Quercus, Castanosis pollen shows a high percentage, whereas Juglans and Casta-nea are very small in number. Among the needle-leaved trees, Cryptonzeria as well as Pinus appears with a great percentage, but the others, e.g. Tsuga, Abies and Sciadopitys, are ex-tremely few.<br> (2) Nonarboreal Pollen (NAP)<br> Crarnineae, and Compositae next to it, prevail in most of the sites. In addition to these, we recognize only a few Plantago, Partinia, Persicaria, Ciienopodiaceae, Cyperaceae, Liliaceae, , Stellaria, Ainaranthus, etc..<br> The NAP and the pollen of shrubs, of all the above-mentioned pollen, is considered to reflect the local vegetation which existed near the sites in the Yayoi era because pollen of this kind is rarely transported a long distance. It is not certain where the other pollen came from. Yet it might be inferred, from the instance of forest relics of Toro site (Shizuoka Prefecture), that forests consisting of pine, cedar, oak trees, etc, were on the natural levee along the river and that rice was grown in the back marshy land. It is to be noted, however, that we can not possibly imagine a dense forest found in the middle of a basin of the Yayoi era, because the flood of rivers in those days, which brought about the alluvion, caused destruction of vege-tations as well.<br> Lastly, it is also important that vegetations of the Yayoi era in Japan formed an economic basis in the sense that they yielded wooden agricultural implements and that rice was cultiva-ted in the marsh.

収録刊行物

  • 地理学評論

    地理学評論 44 (10), 707-722, 1971

    公益社団法人 日本地理学会

被引用文献 (1)*注記

もっと見る

キーワード

詳細情報 詳細情報について

問題の指摘

ページトップへ