REARRANGEMENT OF LAND AND WATER UTILIZATION IN RECLAIMED LAND (THE COASTAL AREA IN THE INLAND SEA OF SETO)

本研究的结果概述如下：1。濑户内海沿海地区发展历程的历史回顾与近现代课题：濑户内海沿海地区的国土和水资源开发经历了三个阶段。这些阶段的历史痕迹仍然存在于土地和水的现代利用中。今天，它已经开始重新安排利用系统。用水系统的重新安排：在非农业经济活动显著增加的今天，有必要重新安排过去为农业建造的用水系统和水渠系统。为完善这一系统，实施了全国灌溉工程。结果表明，这种重新安排使水资源利用效率降低，产生了新的用水需求。海水复垦土地的集约利用和排水基础设施的改善：在过去开垦的农业生产用地较多的情况下，目前正在进行土地集约利用，即城市化或农用地综合利用的改善。径流特征发生变化，防洪安全水平明显下降。可见，城乡区域排水设施泵站和排水渠是由土地改良机构改造的，其目的和技术内容与传统的农业排水不同。土地改良制度在区域发展中的作用和未来的主体：重新安排该区域的土地和水利用系统将成为最重要的问题。结论认为，这一安排应主要作为全国性的土地整治工程进行。同时指出，在改善沿海地区的同时，也要改善上游的雨水汇流区——后山区。少

Results from this research are outlined as follows.1. The historical review of developing process of the coastal area in the Inland Sea of Seto and modern subjects of this area: There are three stages in land and water resources development in this area. The historical trace of those stages remains in the modern utilization of land and water. Today it has already started to rearrange the utilization system.2. Rearrangement of the water use system: As economical activity in non-agriculture sector remarkably raises in the area today, it is necessary to rearrange the water use system and the canal system constructed in the past for agriculture. The national oriented irrigation project is undertaken to improve the system. As its results, it is clear by this investigation that the efficiency of water utilization decreases and the new water demand occurs by this rearrangement.3. The intensive use in sea water reclaimed land and the improvement of infra-structures for drainage: In the reclaim … More ed land for agricultural production in the past, the intensive land use, that is, urbanization or improvement for multi-purpose agricultural land use is progressed in the present. The runoff characteristics change and the safety level against flood damage remarkably goes down. It is clear that the regional drainage facilities for both of the rural and urban area, pump station and drainage canal, are used to be improved by the land improvement institution, and its purpose and technical contents are changing from the conventional agricultural drainage.4. The role of the land improvement institution and the future subject in the development of the area: It will become the most important problem to rearrange the land and water utilization system in this area. It is concluded that this arrangement should be undertaken mainly as the national oriented land improvement project. It is also pointed out that it is important to improve the behind mountainous area, which is a catchment area of rainfall in the upstream, at the same time of improvement for the coastal area. Less