オゾン層の減少:南極海の紫外線と植物プランクトン生物学
R C Smith1, B B Prézelin, K S Baker
1Department of Geography, University of California, Santa Barbara 93106.
まとめ
南極の上のストラトスフィアのオゾン (O3) 減少は,南洋の有害な紫外線 (UVB) 放射を増加させる. このUVB放射線は植物プランクトンの光合成を阻害し,南極の海洋生態系における一次生産を減少させます.
科学分野:
- マリン・バイオロジー マリン・バイオロジー
- 海洋学 海洋学とは
- 大気科学 大気科学
背景:
- 南極のオゾン層は,春に大幅に薄くなり,海洋表面でのUVB放射を増加させます.
- 氷の限界地帯の植物プランクトンは,UVBの上昇に脆弱であり,海洋生態系に潜在的に影響を与える可能性があります.
研究 の 目的:
- ストラトスフィアのオゾン層の減少がUVB放射線と植物プランクトンの光合成に及ぼす影響を調査するため,ベルリングハウゼン海.
- 南極海域の原産物に対するUVBの増加の影響を定量化するために.
主な方法:
- 1990年の南極の春,ベルリングハウゼン海で6週間の研究クルーズ (Icecolors) をしました.
- 海面と深度によるUVBと総照射率の比率の測定.
- 植物プランクトンの光合成に対するUVB阻害の評価.
主要な成果:
- オゾン薄化は,UVB/総照射比率の増加と相関しています.
- 紫外線 (UVB) の増加は,植物プランクトンの光合成を著しく抑制した.
- オゾン層の劣化による原産物の減少は6~12%と推定されている.
結論:
- オゾン層の枯渇は,水中のスペクトル放射線を変化させ,植物プランクトンの生理学的プロセスに影響します.
- オゾン層の薄れによるUVBの浸透は,南極海の一次生産性を脅かしている.
- 植物プランクトンの動態の変化は,南極の海洋生態系にカスケード効果をもたらす可能性があります.
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