Method of Planning for Irrigation Pond Conservation and Improvemet Considering Surrounding Areas Environment

近年来，关于灌溉池塘的保护与改造，我们所要考虑的问题也越来越多。老堤的结构特点决定了对老堤进行周期性加固的必要性。因此，我们认为有必要在单独改善每个池塘的机会下，将灌溉池塘及其周边环境一起改善。既然如此，就有必要事先掌握每个灌溉池塘需要什么样的维护，同时了解它的老化程度。本研究的目的在于探讨灌溉池塘保护与改善规划的方法，并以周边环境为考量。本文对灌溉池塘的分组方法和确定池塘老化程度的测量方法进行了研究，第一章结合香川县的实际情况，介绍了将各池塘分组的方法及其应用。我们只使用已收集的数据来划分方法。第二章也讨论了同样的方法。然而，我们将其应用于香川县三川镇作为主成分分析和聚类分析的分组方法。第三章以三川镇230座灌溉塘坝为对象，介绍了调查方法。本文论述了灌溉池塘的调查项目、实际情况调查、问卷调查、AHP法分析、评价项目权重的确定、池塘老化程度的估算。可以看出，灌溉池塘可以根据退休的程度，在行列中安排。

Recently, it comes to diversify that the matters we should consider on the conservation and improvement of irrigation pond. It is periodically necessary to improve superannuated dike because of stuructual feature. Therefore, we consider it necessary to improve irrigation pond and its surrounding areas environment together at the oppotunity to improve each pond seperately. Since that is so, it is previously necessary to grasp what kind of maintenance is required for each irrigation pond and what is superannuated degree of it at the same time. The aim of this study is to clarify the method of planning for irrigation pond conservation and improvement considering surrounding areas environment. This report deals with studies on the grouping method of irrigation pond and surveying method in order to decide superannuated degree of it.The first chapter deals with the method which making each pond into some groups in conection with the way of maintenance to applying in Kagawa prefecture. We divise the method using publised data only. Useful results could be obtained through the wide area like prefecture.The second chapter discusses the same method. However, we applied it in Sangawa town of Kagawa prefecture as the grouping method by principal component analysis and cluster analysis. We could presented the useful method at the level of local goverment as townsThe third chapter deals with the surveying method about 230 irrigation ponds which became the object in Sangawa town. We discuss surveying items of irrigation pond, investigation of the actual conditions, analysis through questionnaire by AHP method, decision of the weight value about evaluated items, and estimation of superannuated degree of the ponds. It becomes clear that the irrigation pond can be arranged in ranks according to the superannuated degree.