Phosphorus Cycling between Sediment and Overlying Water in Ben Chifely Reservoir, Australia under Simulated Core Incubation

Environment and Natural Resources Journal

AKM M Rahman¹  Dhia Al Bakri² 

[1] Department of Agriculture and Water Resources, Mascot, New South Wales 2020, Australia;Facuty of Science, University of Sydney, Camperdown, New South Wales 2050, Australia;

关键词: Phosphorus;    Sediment;    Overlying water;    Core incubation;    P fractions;    Oxic;    Anoxic;   

DOI  :  10.14456/ennrj.2018.11

来源: DOAJ

【 摘 要 】

The flux of soluble reactive phosphorus (SRP) was estimated under simulated oxic, anoxic and aerated conditions in sediment cores collected from two sites in ameso-eutrophic reservoir that differ in depth and limnological characteristics. Hypolimnetic accumulation and the concentration of P in various sediment fractions were also studied to determine the factors and processes influencingSRP flux at the sediment-water interface. The average release of SRP under anoxic incubation varied between 16 - 70 µmol/m2/day and 20 - 94 µmol/m2/day in shallow and deep-water sites respectively. On the other hand, SRP was almost entirely lost to the sediment during simulated oxic or aerated experiments. Temperature influence on P release from the sediment was significant and the increment is considerable at water temperature above 20oC. The reservoir sediment contained a large proportion of iron and aluminum bound P (Fe and Al-P). Fe and P ratio in the sediment exceeded 15 indicating high retention capacity of P by the sediment. Besides, the high amount of Fe and Al-P in the sediment reflects redox dependent P mobilization. Therefore, management needs targeting retention capacity of the sediment and alteration of anoxic condition in the hypolimnion during warmer months.

【 授权许可】

Unknown