古代帝都の自然環境と長岡京について

抄録

Among persons who have thought about the old capital at Nagaoka (784-794, the capital directly preceeding the one at Kyoto and to the south-west of modern Kyoto), there have been some who believed that the fact that in its center an ancient flood plain extended from north to south and that in its southeast quadrant there was a wet depression was an important reason for abandoning it. Having myself personally walked over the sites of the capitals which succeeded one another after the Taika Reform, 646 A.D., at Naniwa, Asuka, Otsu, Fujiwara, Heijo, Kuni, Heian, I have thought upon the natural conditions peculiar to the founding of the capitals.
The first one was built along the upper reaches of the Asuka River where floods were few, and the later capitals gradually moved down toward broad plains and to wide slopes giving way to the southward. Still it is clear that the imperial palace which was the center of these capitals always stood upon an eminence or on the slope of one. And as their populations grew sites abundant in sail and water resources were looked upon with faver as capitals. As a result I perceived that Nagaoka with its hillock must have been a rather desirable site. I found, too, that the damp bottoms in its southeast were not in the old times flooded as much as people think. Therefore, I think it is not suitable to say that Nagaoka was abondoned because its site was disadvantageous.