Development of maintenance means that mitigates risks of ecosystem conservation facilities

研究表明，生态系统保护设施在保护生物多样性方面发挥了重要作用，但同时也降低了渠道的承载能力，使渠道内的物质流趋于均匀。生态系统变迁的测度方法也不断发展。很明显，铲土和割草对农民来说是繁重的劳动。在老龄化的农村地区，铲平和砍伐是引入生态保护设施的障碍。生态系统保护设施的建设要求：1）考虑环境因素，如上游的土地利用，2）有必要根据人工维护能力，研究半自然施工法与传统施工法的结合考虑遗传特性可能需要网络的运河。

It was confirmed that ecosystem conservation facilities pose depression of canal ability and homogenization of material flow in canals, although it contribute largely to conserve biodiversity. Some methods were developed to measure transition of ecosystem. It became clear that to shovel dirt and to cut grass were heavy labor for farmers. Shoveling and cutting would be obstacles to introduce ecosystem conservation facilities to aging rural area. Inhabitation of small group that had genetic polymorphism locally was observed.Requirement for construction of ecosystem conservation facilities are as follows.1) To consider environmental elements, for example land use in upper reaches, that determine quantity of sediment is important.2) It is necessary to examine combination of Semi-natural construction method and traditional method depending on the maintenance ability by humans.3) To consider genetic characteristics may be needed for networking of canals.