Warming and chlorophyll-<i>a</i> abundance in reservoirs: empirical analysis using a latitudinal gradient in Japan

DOI Web Site Web Site 31 References
  • URABE Jotaro
    Graduate School of Life Sciences, Tohoku University
  • MARUOKA Natsumi
    Graduate School of Life Sciences, Tohoku University Center for Bioscience Research and Education, Utsunomiya University
  • ENOMOTO Megumi
    Graduate School of Life Sciences, Tohoku University Fisheries Resources Institute, Japan Fisheries Research and Education Agency
  • Takenaka TAKANO Kohei
    Graduate School of Life Sciences, Tohoku University Nagano Environmental Conservation Research Institute
  • ICHIYANAGI Hidetaka
    Water Resources Environment Center
  • OGURO Michio
    Graduate School of Life Sciences, Tohoku University Forestry and Forest Products Research Institute
  • ISHIGOOKA Yasushi
    Nemuro Upland Farming Research Division, Hokkaido Agricultural Research Center, National Agriculture and Food Research Organization
  • NAKASHIZUKA Toru
    Graduate School of Life Sciences, Tohoku University Forestry and Forest Products Research Institute

Bibliographic Information

Other Title
  • ダム湖におけるChlorophyll-<i>a</i>量への温暖化影響：経験モデルによる解析
  • ダム湖におけるChlorophyll-a量への温暖化影響 : 経験モデルによる解析
  • ダムコ ニ オケル Chlorophyll-aリョウ エ ノ オンダンカ エイキョウ : ケイケン モデル ニ ヨル カイセキ

Search this article

Abstract

<p>　Chlorophyll-a (chl-a), which reflects algal abundance, is an important determinant of water quality in lakes and reservoirs. In this study, we analyzed the mean chl-a abundance from 1990 to 2010 in 91 dam reservoirs located in southern and northern Japan. Although no significant annual trend in chl-a abundance was detected in all reservoirs during the observation period, we found a significant positive relationship between chl-a abundance and warmth index (or mean temperature) across the reservoirs. Using this relationship, we projected the chl-a abundance for 2076–2100 in each reservoir using a global climate model under the RCP 8.5 scenario. The results showed that the chl-a abundance in 2076–2100 was 2.2 times higher than the maximum abundance in the study period and, on an average, 1.5 times higher than that in 2000. To examine whether this increase in chl-a abundance could be attributed to the direct effects of warming, we further analyzed chl-a abundance using a structural equation model that included the indirect effects of warming through changes in land use/land cover in the reservoir watersheds. When indirect effects were considered, the direct effect of warming on chl-a abundance was no longer significant. Instead, the chl-a abundance was significantly related to the indirect effects of warming through changes in land use/land cover components in the watersheds. Based on these results, we discuss the importance of land use/land cover policies in managing the water quality in reservoirs under the influence of global warming.</p>

Journal

References(31)*help

See more

Keywords

Details 詳細情報について

Report a problem

Back to top