Continuous Flow Analysis Method for Determination of Dissolved Reactive Phosphorus in Ice Cores

TY - JOUR

T1 - Continuous Flow Analysis Method for Determination of Dissolved Reactive Phosphorus in Ice Cores

AU - Kjær, Helle Astrid

AU - Vallelonga, Paul Travis

AU - Svensson, Anders

AU - Elleskov L. Kristensen, Magnus

AU - Tibuleac, Catalin

AU - Bigler, Matthias

PY - 2013/11/5

Y1 - 2013/11/5

N2 - Phosphorus (P) is an essential macronutrient for all living organisms. Phosphorus is often present in nature as the soluble phosphate ion PO 43- and has biological, terrestrial, and marine emission sources. Thus PO43- detected in ice cores has the potential to be an important tracer for biological activity in the past. In this study a continuous and highly sensitive absorption method for detection of dissolved reactive phosphorus (DRP) in ice cores has been developed using a molybdate reagent and a 2-m liquid waveguide capillary cell (LWCC). DRP is the soluble form of the nutrient phosphorus, which reacts with molybdate. The method was optimized to meet the low concentrations of DRP in Greenland ice, with a depth resolution of approximately 2 cm and an analytical uncertainty of 1.1 nM (0.1 ppb) PO43-. The method has been applied to segments of a shallow firn core from Northeast Greenland, indicating a mean concentration level of 2.74 nM (0.26 ppb) PO43- for the period 1930-2005 with a standard deviation of 1.37 nM (0.13 ppb) PO4 3- and values reaching as high as 10.52 nM (1 ppb) PO 43-. Similar levels were detected for the period 1771-1823. Based on impurity abundances, dust and biogenic particles were found to be the most likely sources of DRP deposited in Northeast Greenland.

AB - Phosphorus (P) is an essential macronutrient for all living organisms. Phosphorus is often present in nature as the soluble phosphate ion PO 43- and has biological, terrestrial, and marine emission sources. Thus PO43- detected in ice cores has the potential to be an important tracer for biological activity in the past. In this study a continuous and highly sensitive absorption method for detection of dissolved reactive phosphorus (DRP) in ice cores has been developed using a molybdate reagent and a 2-m liquid waveguide capillary cell (LWCC). DRP is the soluble form of the nutrient phosphorus, which reacts with molybdate. The method was optimized to meet the low concentrations of DRP in Greenland ice, with a depth resolution of approximately 2 cm and an analytical uncertainty of 1.1 nM (0.1 ppb) PO43-. The method has been applied to segments of a shallow firn core from Northeast Greenland, indicating a mean concentration level of 2.74 nM (0.26 ppb) PO43- for the period 1930-2005 with a standard deviation of 1.37 nM (0.13 ppb) PO4 3- and values reaching as high as 10.52 nM (1 ppb) PO 43-. Similar levels were detected for the period 1771-1823. Based on impurity abundances, dust and biogenic particles were found to be the most likely sources of DRP deposited in Northeast Greenland.

KW - Faculty of Science

KW - Continuous flow analysis (CFA)

KW - Fosfat

KW - Greenland

KW - Ice

U2 - 10.1021/es402274z

DO - 10.1021/es402274z

M3 - Journal article

C2 - 24128116

SN - 0013-936X

VL - 47

SP - 12325

EP - 12332

JO - Environmental Science & Technology

JF - Environmental Science & Technology

IS - 21

ER -