アメリカ全土の流れネットワークの長さの変動
Jeff P Prancevic1,2, Hansjörg Seybold2, James W Kirchner1,2,3
1Department of Earth & Planetary Science, University of California, Berkeley, Berkeley, CA, USA.
まとめ
流のネットワークは 景観の湿度と共に拡大し 収縮します アメリカ全土で,流量が高い時期は流量低い時期の5倍の長さで,水文学的変化が顕著である.
科学分野:
- 水学
- 地形学
- 環境科学
背景:
- 流のネットワークのダイナミクスは,水文学的プロセスを理解するために不可欠です.
- 流れのネットワークの変動に関する以前の研究は,小さな排水盆地に限られていた.
- 流れる小川の総長さに大きく影響する.
研究 の 目的:
- 広い地域におけるストリームネットワークの長さの変動を推定する.
- 景観の湿度と川のネットワークの範囲の関係を定量化する.
- ストリームネットワークのダイナミクスにおける地域差を特定する.
主な方法:
- 川の流れを測定したアメリカ合衆国の 14,765の流域のデータを利用した.
- ネットワークの弾性 (湿度に対する感受性) を推定するために,地形に基づいた方法を使用した.
- ストリームネットワークの長さをモデル化するためのネットワークの弾性を持つ統合されたストリーム流の分布.
主要な成果:
- 平均的なアメリカ流のネットワークは,年間高流量状態では,年間低流量状態と比較して5倍長くなることが判明しました.
- ストリームネットワークの動態には,米国全体で顕著な地域差が見られた.
- 水気気候とネットワークの弾力性は,地域差の主要な要因として特定されました.
結論:
- 流れのネットワークは,変化する水文条件に反応して,かなりの長さの変動を示します.
- 地域の水候要因と風景の特徴は,流れのネットワークのダイナミクスを調節します.
- 結果は,気候の変動に対するストリームネットワークの反応に関する国家規模の見通しを提供します.
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