Baturin,G.N.(2003): Phosphorus cycle in the ocean. Lithology and Mineral Resources, 38(2), 101-119.

『海洋におけるリン循環』


Abstract
 The behavior of phosphorus is considered at major stages of the sedimentary cycle beginning with supply sources for its delivery into the ocean to precipitation and its sedimentation, localization and subsequent diagenetic redistribution in bottom sediments. River runoff represents the main phosphorus source in the ocean. It delivers annually about 1.5 Mt of dissolved phosphorus and more than 20 Mt of suspended phosphorus into the ocean. Up to 80% of the suspended phosphorus incorporated in the lithogenic material precipitates within submarine continental margins. Phosphorus dissolved in seawater repeatedly participates in biogeochemical processes owing to its assimilation by phytoplankton that annually consumes from 1.5 to 2.5 Gt of phosphorus. Dissolved phosphorus is incorporated in organic remains and precipitates from seawater by a biogenic mechanism, too. Only a part of phosphorus settled onto the bottom is buried in sediments. Due to reducing diagenetic processes, up to 30-40% of the primarily precipitated phosphorus diffuses from the upper layer of sediments into bottom water. Diffusion flux into the ocean significantly exceeds the supply of dissolved phosphorus from river runoff. The absolute mass phosphorus dispersed in sediments is several orders of magnitude greater than the mass concentrated in phosphorite deposits. However, the majority of phosphorite formation epochs coincide with the intensification of total phosphorus accumulation in marine sediments in conditions of humid climate, intense chemical weathering of rocks on continents, and considerable expansion of the oceanic shelf area.』

(Introduction)
Phosphorus delivery into the world ocean
Phosphorus in oceanic water, suspended matter, and biota
Phosphorus precipitation from oceanic waters
Phosphorus in marine and oceanic sediments
Phosphorus in pore water
Phosphorus flux from sediments into bottom water
Phosphorus residence time in oceanic waters and its budget
Phosphorus cycle, climate, and phosphorites
Conclusions
Acknowledgements
References

Table 1. Total present-day phosphorus supply into the World Ocean (Savenko, 2001)

Source

Supply, Mt/yr
River runoff 24.2
Glacier discharge and glacier erosion 1.4
Groundwater discharge 0.1
Coastal abrasion 0.4
Atmospheric precipitation 1.7
Volcanism of active continental margins 3.3
Total 31.1

Table 2. Forms of present-day and preanthropogenic phosphorus supply into the World Ocean, Mt/yr (Compton et al., 2000)

Phosphorus sources and species

Preanthropogenic supply

Present-day supply
1. River runoff    
 Dissolved P:    
  inorganic 0.3-0.5 0.8-1.4
  organic 0.2 (maximum) 0.2 (average)
 Suspended P:    
  inorganic 0.9 (maximum) 0.9 (average)
  organic 1.5-3.0 1.3-7.4
  detrital 6.9-12.2 14.5-20.5
2. Eolian 1.0 (including 20% of reactive P) 1.05 (including 20% of reactive P)
Total 10.8-17.8 18.7-31.4
Reactive 3.1-4.8 3.4-10.1


Fig. 1. Phosphorus distribution (%) in the upper sediment layer of the World Ocean, based on data from (Baturin, 1988; Baturin and Sevast’yanova, 1986; Baturin et al., 1995; Emel’yanov and Romankevich, 1979). (1) <0.05%; (2) 0.05-0.1%; (3) 0.1-0.2%; (4) 0.2-0.3%; (5) >0.3% (for the Indian ocean: (2) 0.05-0.08%; (3) >0.08%)

Baturin(2003)によるPhosphorus cycle in the oceanから

Table 6. Phosphorus species in sediments, % of total P content (Berner et al., 1993)

Species

Region

Mississippi delta

Amazon delta

Long Island Sound

Equatorial Atlantic

Black Sea
Organic P 29 26 20 27 43
P bound with iron hydroxides 23 46* 0 20 19
P bound with carbonates 28 22 29 49 20
Detrital P 15 6 47 1 11
Absorbed P 5 - 4 2 7
Total P, % 0.067 0.054 0.059 0.078 0.061
Number of samples 18 12 6 6 13


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