[A-CG41] 植物プランクトン増殖に関わる海洋－大気間の生物地球化学

[ACG41-05] Impact of atmospheric iron inputs on marine primary productivity and nutrient cycling

*三角 和弘¹、津旨 大輔¹ (1.電力中央研究所 環境科学研究所)

キーワード：鉄、栄養塩、数値シミュレーション

A micronutrient iron regulates marine primary productivity roughly one-third of the global ocean. Change in atmospheric iron deposition has been regarded as a factor controlling past climate changes through changing CO₂ uptake by the ocean. Current global-scale marine biogeochemical models are using different iron deposition products derived from various atmospheric transport models. The total amounts of bioavailable iron supplied to the ocean vary 1.4–32.7 Gmol yr^-1 among the models, being a large uncertainty to project future oceanic CO₂ uptake. The variation of the iron supply rates can be attributed to 1) difference in the total iron deposition rate, 2) treatment of atmospheric processing determining the solubility and 3) treatment of consecutive dissolution of iron from sinking particles in the ocean. In this talk, we will address impact of atmospheric iron inputs on marine primary productivity and nutrient cycles by reviewing previous studies and results from some idealized experiments.