透過型砂防ダムの渓流生態系保全機能に関する実証的研究

Research Project

Project/Area Number	13660152
Research Category	Grant-in-Aid for Scientific Research (C)
Allocation Type	Single-year Grants
Section	一般
Research Field	林学
Research Institution	Minamikyusyu University
Principal Investigator	KITAMURA Hirokazu Minamikyusyu University Faculty of Environmental Landscape Proffesor, 園芸学部, 教授 (90214816)
Co-Investigator(Kenkyū-buntansha)	HIROSE Daisuke Minamikyusyu University Faculty of Environmental Landscape Proffesor, 園芸学部, 教授 (80269125)
Project Period (FY)	2001 – 2002
Project Status	Completed (Fiscal Year 2002)
Budget Amount *help	¥2,000,000 (Direct Cost: ¥2,000,000) Fiscal Year 2002: ¥900,000 (Direct Cost: ¥900,000) Fiscal Year 2001: ¥1,100,000 (Direct Cost: ¥1,100,000)
Keywords	stream-environment conservation / permeable sabo dam / aquatic-insect assemblage / drift of aquatic insect / litter dynamics / stream-water quality / material cycle in a stream / decompositin of instream material / 渓流生態系保全 / 水生生物群集 / 攪乱体制 / 不透過型砂防ダム / 羽化行動 / 地表変動履歴 / 多自然型渓流整備
Research Abstract	(1) A pattern of aquatic-invertebrate assemblage in relation to the fragility of stream bed due to the of erosion control work in the stream was observed by the comparative analysis of aquatic-invertebrate assemblage with the fragility of the stream beds estimated by the ratio friction speed to critical friction velocity. (2) While the progress of erosion control work in a stream affects life styles of an certain species of aquatic-invertebrate assemblage, inducing the variation of aquatic-invertebrate assemblage of the stream, it was statistically supported by multivariate analysis of variance that permeable sabo dam influences hardly aquatic-invertebrate assemblage. (3) In a stream bed where impermeable sabo dams are constructed, extreme deposit and subsequent decomposition of litters were observed because stagnant zones dominate due to monotonic water depth and flow velocity. Therefore, it was suggested that stream water quality depends on existing vegetations as well as bed rocks in the stream. (4) Aquatic insects tend to drift to seek for alternative habitats in a stream where impermeable sabo dams are constructed, but this tendancy is not remarkable in the permeable sabo dam constructed stream.