東北太平洋の深い地域における食糧供給と需要の間の長期間の不一致
1Marine Biology Research Division, Scripps Institution of Oceanography, University of California, San Diego, La Jolla, CA 92093-0202, USA. Marine and Environmental Studies Program, University of San Diego, 5998 Alcala Park, Sa.
Science (New York, N.Y.)
|May 15, 1999
まとめ
東北太平洋で深海の食糧供給が減少している. 7年間の研究では,沈下する微粒子の有機炭素 (POC) が減少し,堆積物コミュニティの酸素消費量 (SCOC) と深海の生態系に影響を与えた.
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 海洋学
- 深海の生態学 深海の生態学
背景:
- 北太平洋の底なしの東部は,限られた食料の利用が特徴である深海環境である.
- 堆積物コミュニティの酸素消費量 (SCOC) は,深海の食糧需要の代理として機能します.
- 沈没する微粒子有機炭素 (POC) は,深海への主要な食糧供給源です.
研究 の 目的:
- 太平洋北東部における食料供給 (POC) と食料需要 (SCOC) の長期的傾向を評価する.
- 表面の海洋状態と深海の食糧の利用可能性との関係を調査する.
- 観測された傾向が深海の生態系と地化学サイクルに及ぼす潜在的な影響を評価する.
主な方法:
- POC流とSCOCをモニタリングするために7年間の研究が行われました.
- 海面温度とプランクトンバイオマスに関するデータを分析した.
- POCとSCOCの比率は,需要に対する食料供給を評価するために計算されました.
主要な成果:
- 深刻な東北太平洋地域では,長期にわたる食糧供給の大きな赤字が観測されました.
- POC:SCOC比率は1989年から1996年の間に52%から59%に減少した.
- この減少は,海面温度の上昇と,地表水のプランクトンバイオマスの減少と関連し,POCの輸出を減少させている可能性がある.
結論:
- 東北太平洋の深海は,食糧供給の減少を経験しています.
- POCの輸出の継続的な減少は,深海の地化学サイクルを大幅に変化させる可能性があります.
- 観測された傾向は,深海のコミュニティの構造と動態に大きな変化をもたらす可能性があります.
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