Diurnal Fluctuation in Stream Flow and in Water Quality by Evapotransplration During Summer Drought Periods

夏季干旱期间河流流量和蒸腾水质的日波动

• 批准号: 01490002
• 负责人: KOBAYASHI Daiji
• 金额: $ 3.26万
• 依托单位: Hokkaido University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (B)
• 财政年份: 1989
• 资助国家: 日本
• 起止时间: 1989 至 1991
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-01490002/
• 关键词: Summer Drought; Water Quality; Evapotranspiration; Diurnal Fluctuation in Flow; Diurnal Fluctuation in Waterquality; 渇水期の水質; 渇水流量の日変動

In a headwater basin covered with boreal forest in northern Japan, drought flow was observed in winter and in summer. In summer drought it was found that remarkable diurnal fluctuation of stream flow and of electric conductance is caused by daytime evapotranspiration. It was found that the daily reduction in stream flow, was accompanied by a reduction in the HCO_3^- ion concentration.The drought hydrograph was separated into two components, assuming the drought flow to be a mixture of surface flow and of shallow flow entering the stream in its lower reaches.(1) Caused by the deficency in rainfalls in summer in this basin, flow rate decreases exponentially from the snowmelt period to the summer drought period.(2) Stormflow in summer low-flow period reduces more rapidly than that in snowmelt period and flow comes back onto the long-term recession trend in 2 or 3 days after storm runoff.(3) The chemical composition of water was analyzed on HCO_3^-, Cl^-, SO_4^=, NO_3^-, Na^+ and K^+. HCO_3^- occupied about 2/3 of the total anions and Cl^- did about 1/3 in equivalent concentration. The diurnal fluctation in the stream conductance was found to be caused by the fluctuation in HCO_3^-ion concentration.(4) The fluctuation in flow components, subsurface and shallow water was estimated to be caused by evapotranspiration near the stream channel, resulting in the diurnal fluctuation in HCO_3^- ion concentration.

在日本北方被北方森林覆盖的源头盆地，冬季和夏季观察到干旱流。在夏季干旱时，径流量和电导率的日变化都是由白天蒸散量引起的。结果表明，河川径流量的日减少伴随着HCO_3 ~-浓度的减少，干旱过程线可分为两个分量，假定干旱流是地表流和下游入流的浅水流的混合。(1)该流域夏季降水不足，从融雪期到夏旱期流量呈指数衰减。(2)夏季枯水期暴雨径流量比融雪期减少得快，暴雨径流后2 ~ 3d内流量又恢复到长期衰退趋势。(3)分析了水的化学组成，包括HCO_3^-、Cl^-、SO_4^-、NO_3^-、Na^+和K^+。HCO_3^-约占阴离子总量的2/3，Cl^-约占1/3。流导的日变化是由HCO_3^-离子浓度的变化引起的。(4)水流分量、次表层水和浅水的波动可能是由于河道附近的蒸散引起的，从而导致HCO_3^-离子浓度的日变化。

项目成果

Tomoyuki NANRi, Kaichiro SASA, Koichiro FUJIWARA, Fuyuki SATO, Tohru ARAYA and Osamu SHIMIZU: "A study on Winter Scanty Runoff Characteristics in small Basins, Northern Hokkaido" Research Bullentins of the College Experiment Forests, Faculty of Agricultur

Tomoyuki NANRi、Kaichiro SASA、Koichiro FUJIWARA、Fuyuki SATO、Tohru ARAYA 和 Osamu SHIMIZU：“北海道北部小盆地冬季缺水径流特征研究”农学院大学实验林研究公报

DAIJI KOBAYASHI, KEISUKE SUZUKI and MUTSUMI NOMURA: "Diurnal Fluctuation in Stream Flow and in Specific Electric Conductance During Drought Periods" Journal of Hydrology. 115. 105-114 (1990)

DAIJI KOBAYASHI、KEISUKE SUZUKI 和 MUTSUMI NOMURA：“干旱期间溪流流量和比电导的昼夜波动”水文学杂志。

DAIJI KOBAYASHI,KEISUKE SUZUKI and MUTSUMI NOMURA: "DIURNAL FLUCTUATION IN STREAM FLOW AND IN SPECIFIC ELECTRIC CONDUCTANCE DURING DROUGHT RERIODS" Journal of Hydrology. 114. 1-10 (1990)

DAIJI KOBAYASHI、KEISUKE SUZUKI 和 MUTSUMI NOMURA：“干旱时期水流流量和比电导率的昼夜波动”水文学杂志。

橘治国: "森林集水域からの栄養塩の流出" 土木学会北海道支部論文報告集. IIー63. 631-636 (1992)

Harukuni Tachibana：“森林流域的养分径流”日本土木工程师学会北海道分会论文集 II-63（1992 年）。

DAIJI KOBAYASHI,EISUKE SUZUKI and MUTSUMI NOMURA: "DIURNAL FLUCTUATION IN STREAM FLOW AND IN SPECIFIC ELECTRIC CONDUCTANCE DURING DROUGHT PERIODS" Journal of Hydrology. 114. 1-10 (1990)

DAIJI KOBAYASHI、EISUKE SUZUKI 和 MUTSUMI NOMURA：“干旱期间水流流量和比电导率的昼夜波动”水文学杂志。