水工学論文集第60巻
河川魚類の個体数に影響を及ぼす多様な環境要因の相対的重要度の評価：繁殖時期に着目して
2016 年 72 巻 4 号 p. I_445-I_450
詳細
2016 年 72 巻 4 号 p. I_445-I_450
We evaluated the relative importance of flow regimes, water temperature, and water quality influencing on the inter-annual population variability of 20 fish species (1993-99) in the Sagami River, Japan, using a random forests approach. A result indicated that flow regime conditions before and after spawning season (April-August and October-December, respectively) and temperature after spawning season influence the population variability of many species most dominantly (relative importance >15% for 10, 8, and 5 species, respectively). Hence, to mimic the natural variability of these factors particularly in the suggested seasons may contribute to better sustain the ecological healthiness in the Sagami River.
