まとめ
河川からの世界の海洋シリカの輸入量は年間6.1テラモールに修正され,海洋堆積物からの出力のバランスをとります. この研究は,海洋シリコンサイクルに関する理解を深める.
科学分野:
- 地質化学 地質化学
- 海洋学 海洋学 海洋学
- バイオジオケミカルサイクル
背景:
- 地球規模のシリコン循環は,海洋生態系と地質学的プロセスにとって極めて重要です.
- 海洋へのシリシウム酸の投入に関する以前の推定は,正確さが欠けていました.
研究 の 目的:
- 世界海洋へのシリシウム酸の純投入量を修正し,定量化する.
- これらのインプットと海洋沈殿物の生物学的シリカのアウトプットのバランスをとるため.
- バイオジェニックシリカの総生産量と保存率を推定する.
主な方法:
- 河川のシリシア酸濃度の収集と分析.
- 海洋沈殿物の生物学的シリカ埋葬の定量化.
- 表面水の生物学的シリカ生産量の推定.
主要な成果:
- 海洋への修正された純シリシウム酸の輸入量は,主に河川 (平均濃度150μM) から,年間6.1 ± 2.0テラモールシリコンです.
- 堆積物への生体シリコンの純出力は,年間7.1 ± 1.8テラモールシリコンで,入力のバランスをとります.
- バイオジェニックシリカの総生産量は,年間240 ± 40テラモール,保存比率は3%です.
結論:
- 大洋のシリコンの輸入と輸出は,ほぼ均衡している.
- 海洋におけるシリコンの滞在時間は,生物学的吸収に比べて約400年です.
- この研究は,海洋シリコンサイクルの主なパラメータに関する最新の数字を提供します.
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