@article{oai:iwate-u.repo.nii.ac.jp:00015976,
 author = {高橋, 真司 and 菊池, 凛 and 笹本, 誠 and 石川, 奈緒 and 伊藤, 歩},
 issue = {7},
 journal = {土木学会論文集G（環境）, Journal of Japan Society of Civil Engineers, Ser. G (Environmental Research)},
 month = {},
 note = {本研究では農畜産業が盛んな岩手県軽米地域を流れる雪谷川と瀬月内川を対象に底生動物と有機物の炭素・窒素安定同位体比（δ13C・δ15N）を用いて，流域内の人為的な栄養塩負荷が河川生態系に及ぼす影響を評価した．δ13C・δ15Nの結果から，瀬月内川上流を除く地点で人為的な栄養塩負荷の影響が推察された．δ13Cによる餌起源推定の結果，付着藻類が底生動物の主な餌資源として利用され，付着藻類のδ15Nと各摂食機能群のδ15Nとの関係から，調査河川では付着藻類を基盤とする食物網が構築されていることが示唆された．したがって，人為的な栄養塩負荷の影響は付着藻類や付着藻類由来の微粒状有機物を介して底生動物へ伝播し，この影響はダム湖の富栄養化を介してダム下流まで波及していることが推察された．, In rivers where farmlands and livestock farms are scattered throughout the watershed, anthropogenic nutrient loading may affect not only water quality but also the river ecosystem. In this study, we evaluated the effects of anthropogenic nutrient loading on the material cycle and food web in the Yukiya River and Setsukinai River using carbon and nitrogen stable isotope ratios (δ13C and δ15N). We collected macroinvertebrates and food sources (attached algae, leaf, suspended particle organic matter (SFPOM) and benthic particle organic matter (BFPOM)) from study sites. The results of δ13C and δ15N suggested the impact of anthropogenic nutrient loading at all sites except the upstream of the Setsukinai River.The stable isotope two source mixing model based on δ13C revealed that macroinvertebrates consumed mainly attached algae. The significant positive correlation between the δ15N of attached algae and the δ15N of each feeding function groups suggested that a food web based on attached algae was constructed in the study rivers. Therefore, it is suggested that the effects of anthropogenic nutrient loading are propagated to macroinvertebrates through attached algae and FPOM derived from attached algae, and that these effects extend downstream to the dam through eutrophication of the dam lake.},
 pages = {III_1--III_10},
 title = {炭素・窒素安定同位体比からみた河川底生動物群集に及ぼす栄養塩負荷の影響評価},
 volume = {77},
 year = {2021}
}