Expansion of soil void study using X-ray stereoradiography

本研究利用Tokunaga K等人提出的X射线立体照相方法，研究了弥生等时期稻田根系形成孔隙系统的连续性特征和实际情况，结果表明：火山灰土区根系在垂直剖面上形成的孔隙系统在1m范围内变化较小，但在1m范围内变化较大。此外，在浮石中和层的边界，也没有发现由根形成的孔隙系统的间断和消失。日本稻田根系形成的孔隙系统密度由大到小依次为犁底、底土和犁土层。同样在泰国水田，我们在日本也发现了同样的趋势。我们在位于大阪的池岛-福满阁遗址上，检测了弥生时代稻田每一层根发现的孔隙系统的详细图像。我们也认可那些p…的很好的保留更多的矿体系由根形成。通过与现代水田的对比，推测了弥合时代早期水稻植株淤积和移栽的可能性。研究了岩手县70万年至170万年(更新世)火山灰沉积地区根系形成的孔隙系统的耐久特征。结果表明，除最低层各层均有根系形成的孔隙系统外，其存在年限均在40万年以上。关于来自山上的火山灰。Towada和Mt.从1万年前到110万年前的客家大地，发现植物根部形成的孔隙系统并没有衰退。研究了植物蛋白石与根系形成的孔隙系统之间的关系(如化石相的可能性)。从而认识到植物蛋白石在垂直剖面上的变化与根系形成的孔隙系统之间的关系。利用根部形成的孔隙系统，可以推测出该地区的古气候。较少

In this study, we investigated the characteristic of continuity and the actual condition of pore systems formed by roots in the paddy field at Yayoi period and so on by using X-ray stereo radiographic method that originated by Tokunaga K. The results summarized as follows.Changes of physical properties and shape of pore systems formed by roots on vertical profile at volcanic ash soil area were small in 1m range but became large over 1m range. Also, it was not recognized discontinuity and disappear of pore systems formed by roots in the pumice stone and at the border of the layers. Density of the pore systems formed by roots at Japan paddy field decreased in order of plow-sole, subsoil and plow layer. Also in Thailand paddy field, we recognized same trend at Japan.We detected the detailed image of pore systems found by roots in every layer of the paddy field of the Yayoi era at the ruins of Ikezima-Fukumannge that was situated at Oosaka-fu. Also we recognized good reservation of those p … More ore systems formed by roots. As compared with recent paddy field, it suggested the possibility that was puddling and transplantation of rice plants in the early years of the Yayoi era.Endurance characteristic of pore systems formed by roots was investigated with the passage of time at the area of volcanic ash in Iwate prefecture that had deposited from seven hundred thousand years to one million and seven hundred thousand years (Pleistocene). As a result, it was clear expect the lowest layer that every layer had pore systems formed by roots was recognized and existence era of the pore systems formed by roots was over four hundred thousand years. On volcanic ash from Mt. Towada and Mt. Hakkoda that deposited from ten thousand years to eleven hundred thousand years ago, that pore systems formed by roots couldn't find decline.Relationship (like the possibility of facies fossil) between pore systems formed by roots and plant opal was investigated. As a result, relationship of between the change of plant opal in the vertical profile and that of pore systems formed by roots was recognized. By using pore system formed by roots, it was possible to guess the palaeoclimate at the spot. Less