Santner Jakob, Mannel Martina, Burrell Leigh D, Hoefer Christoph, Kreuzeder Andreas, Wenzel Walter W
Vienna, Department of Forest and Soil Sciences, Institute of Soil Research, University of Natural Resources and Life Sciences, Konrad-Lorenz-Strasse 24, 3430 Tulln, Austria.
Plant Soil. 2015 Jan 1;386(1-2):371-383. doi: 10.1007/s11104-014-2271-x.
Sink extraction of phosphorus from soils has been utilised to study soil P desorption kinetics and as index of plant availability, but not for quantitative prediction of P uptake by plants. Here we investigate the potential of a modified sink extraction method for determining P desorption kinetics and for quantifying plant available soil P.
Modified diffusive gradients in thin films samplers were immersed in shaken soil suspensions for long-term extraction of soil P. Results were evaluated in terms of P desorption kinetics and compared to the P uptake of L. and standard soil extracts.
In contrast to literature reports, four of the six studied soils only showed a rapid, but not a slowly desorbing P fraction. The quantity of P desorbed by long-term sink extraction not only showed the highest correlation to plant P uptake, but also matched plant P uptake quantitatively.
Our data indicates that soils with only a fast desorbing P fraction might exist. Sink extraction methods have the potential to quantitatively predict plant P uptake. Furthermore, they could become valuable research tools for understanding P acquisition and might serve as a benchmark for calibrating soil P tests.
利用土壤中磷的汇提取来研究土壤磷解吸动力学，并作为植物有效性指标，但尚未用于定量预测植物对磷的吸收。在此，我们研究一种改良的汇提取方法在确定磷解吸动力学和量化植物有效土壤磷方面的潜力。
将改良的薄膜扩散梯度采样器浸入振荡的土壤悬浮液中，用于长期提取土壤磷。根据磷解吸动力学对结果进行评估，并与番茄对磷的吸收以及标准土壤提取物进行比较。
与文献报道相反，所研究的六种土壤中有四种仅表现出快速解吸的磷组分，而没有缓慢解吸的磷组分。长期汇提取解吸的磷量不仅与植物磷吸收具有最高的相关性，而且在数量上与植物磷吸收相匹配。
我们的数据表明可能存在仅具有快速解吸磷组分的土壤。汇提取方法有潜力定量预测植物对磷的吸收。此外，它们可能成为理解磷获取的有价值的研究工具，并可作为校准土壤磷测试的基准。
