Beschreibung:
<jats:title>Abstract</jats:title><jats:p>Soil fertilization with trace‐metal rich organic fertilizers such as <jats:italic>Fucus serratus</jats:italic> seaweed may be an effective way to combat micronutrient deficiency. In this study the kinetics of zinc release from <jats:italic>Fucus serratus</jats:italic> seaweed was investigated in a packed soil column leaching experiment over 1,776 h. The release of zinc from control (soil only) and treatment (soil + seaweed; equivalent zinc application rate of 1.42 kg ha<jats:sup>−1</jats:sup>) columns, measured by ICP‐MS, demonstrated two distinct release stages. The cumulative zinc release data for each phase were fitted to five kinetic models: zero order, first order, Elovich, power function and parabolic diffusion. In the first stage (0–400 hours) the release of zinc from both control and treatment was best described by a parabolic rate law, indicating release of zinc from a soluble soil reservoir. In the second stage (400–1,776 h) zinc release followed a zero order rate law indicative of slow release from an essentially insoluble reservoir. The modelled difference between the amount of zinc released from treatment and control columns in stage 1 (230 ± 11 µg) represented the total amount of zinc added <jats:italic>via</jats:italic> seaweed. The parabolic rate constant for seaweed zinc release was 12.09 µg g<jats:sup>−1</jats:sup> h<jats:sup>−0.5</jats:sup>. In summary, the addition of <jats:italic>F. serratus</jats:italic> to soil is a viable source of labile zinc and a low cost agronomic option for mitigating zinc deficiency in soils.</jats:p>