アメリカ合衆国 の 保護 区域 に ある プラスチック の 雨
Janice Brahney1, Margaret Hallerud2, Eric Heim2
1Department of Watershed Sciences, Utah State University, Logan, UT 84322, USA. janice.brahney@usu.edu.
まとめ
プラスチックの汚染は環境への懸念が高まっています この研究では プラスチックが大気中で長い距離を移動し 湿った環境か乾燥した環境かによって 異なる堆積パターンがあることが明らかになりました
科学分野:
- 環境科学
- 大気科学
- エコロジー
背景:
- 2025年までに プラスチックの総量は およそ110億トンになると予測されています
- 永続性のあるプラスチックが 細かく砕かれ 風によって大気中に運ばれます
- 微小プラスチックの大気中の運命を理解することは 環境への影響の評価に不可欠です
研究 の 目的:
- 湿ったか乾いたかによる プラスチックの異なる大気の生命の歴史を調査する.
- 割合を定量化し プラスチック堆積の源を 特定するためです
主な方法:
- 高解像度の空間と時間のデータを使って プラスチック堆積を分析した
- 湿気と乾燥状態での大気輸送と堆積パターンを比較した.
- 都市部と再懸浮を含むプラスチック堆積の特定された源
主要な成果:
- 湿った状態で堆積したプラスチックは主に都市部から発生し,土壌や水から再懸浮されます.
- ドライデポジットされたプラスチックはより小さく,より長い距離または地球規模の大気輸送を示します.
- 平均的な堆積量は1平方メートルあたり1日あたり132個で 合計で年間1000トンのプラスチックが アメリカ西部で保護されています
結論:
- プラスチックの堆積は湿気や乾燥状態によって異なる大気経路を示します
- 遠隔地にある自然保護地域では 毎年大量のプラスチックが堆積しており プラスチック汚染が蔓延していることが 明らかになっています
- 都市部での排出と再懸浮は 地域のプラスチック堆積に大きく寄与し 小さな粒子は地球規模での輸送を 示唆しています
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