The Effect of various forest disturbances on water discharge duration curve : The Case Comparison between the Sarukawa experimental watershed in Miyazaki-shi and the Tatsunokuchi-yama experimental watershed in Okayama-shi

Autor: Koji, Tamai, Akira, Shimizu, Ikuhiro, Hosoda, Yasuo, Miyabuchi, Takanori, Shimizu, Takafumi, Miyama, Yuji, Kominami, Shiho, Asano
Jazyk: japonština
Rok vydání: 2008
Předmět:
Zdroj: 森林総合研究所研究報告. 408:111-120
ISSN: 0916-4405
Popis: The effects of forest disturbance on the discharge duration curve were compared among various disturbed cases in the Sarukawa experimenta watershed (hereafter Sarukawa), Miyazaki-shi and Tatsunokuchi-yama experimental watershed (hereafter Tatsunokuchi-yama), Okayama-shi. Defining a significance level as 20-30%, the discharge change was judged to be significant in most cases. Although the maximum discharge increase was larger in the Sarukawa than in the Tatsunokuchi-yama, the discharge increase ratio was smaller. More precipitation was thought to reduce the effect of forest coverage on the discharge processes. Discharge increased ratios in both Tatsunokuchi-yama cases were almost equal to be around 50%. Thus, no significant difference in the effect of forest disturbance on discharge was recognized between the cases with disturbed areas of 100% and 84% in the Tatsunokuchi-yama. By contrast, the increased ratios in Sarukawa cases affecting 100% and 43% of the area were around 20% and 13%, respectively. Thus, the difference in the effect of forest disturbance on discharge was recognized between the cases in Sarukawa with the different disturbed areas.
森林撹乱が流況曲線に及ぼす影響を、宮崎市の去川森林理水試験地と、岡山市の竜ノ口山森林理水試験地における事例間で比較を行った。有意水準を20~30%に設定すると、森林撹乱による流出量の変化は多くの場合で有意差があると判断された。竜ノ口山よりも去川では森林撹乱による推定増加流出量の最大値は大きかったが、増加流出割合は小さかった。これは降水量が多い場合には、森林の流出量への影響が相対的に小さくなるためと思われた。流況曲線の100~275日目の範囲において、竜ノ口山における撹乱面積率100%と84%の事例での増加流出割合はともに約50%であり、影響度の違いは見いだせなかった。一方、去川における撹乱面積率100%と43%の事例による増加流出割合はそれぞれ約20%と約13%と、違いが認められた。
Databáze: OpenAIRE