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Fusion of Secretory Vesicles with the Plasma Membrane
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フラクタルストリームの化学と,流域内の汚染物質の輸送への影響
1Department of Geology and Geophysics, University of California, Berkeley 94720-4767, USA. kirchner@seismo.berkeley.edu
Nature
|February 17, 2000
まとめ
塩化物トレーサーを用いて測定された漁場移動時間は,単一の特徴的な洗浄時間がありません. 代わりに,パワー・ローの分布は,長い化学記憶を示唆し,低レベルの汚染物質の放出を長引かせる.
科学分野:
- 水文学 水文学とは
- 環境科学 環境科学
- 地質化学 地質化学
背景:
- ストリームフローの汚染物質の輸送は,採集区の洗浄時間によって管理されます.
- 短い洗浄時間は強い汚染物質のパルスを引き起こし,長い時間は持続的な流れを引き起こします.
- 流域の移動時間を理解することは,下流の汚染影響を予測するために非常に重要です.
研究 の 目的:
- 集水域の移動時間の分布を理解するために,ヘッドウォーターの集水域からのトレーサーデータを分析する.
- 降雨と川の流れにおける塩化物濃度のスペクトル特性を調査する.
- 流域が特徴的な洗浄時間または移動時間のパワー・ロー分布を示すかどうかを判断する.
主な方法:
- 降雨と流れの塩化物濃度に関するタイムシリーズデータの分析.
- トレーサー濃度のパターンを特定するために,スペクトル解析の適用.
- フラクタル1/fスケーリングと力法則分布の調査.
主要な成果:
- 降雨中の塩化物濃度は,白いノイズスペクトルを示した.
- 流水中の塩化物濃度は,フラクタル1/fのスケーリングを3桁の大きさで示した.
- 釣り場の移動時間は,特徴的な洗浄時間ではなく,およそパワー・ロー分布に従った.
結論:
- これらの頭部流域は,電力法による分散移動時間により,長い化学記憶を持っています.
- 最初の汚染物質の洗浄は迅速で,その後は低レベルの放出が長期間続く.
- 特徴的な洗浄時間の欠如は,汚染エピソードの管理に重大な影響を及ぼします.
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