Facilia AB, Gustavslundsvägen 151C, 167 51 Bromma, Sweden.
J Environ Manage. 2013 Sep 15;126:147-56. doi: 10.1016/j.jenvman.2013.03.055. Epub 2013 May 28.
Contaminant concentrations in various edible plant parts transfer hazardous substances from polluted areas to animals and humans. Thus, the accurate prediction of plant uptake of elements is of significant importance. The processes involved contain many interacting factors and are, as such, complex. In contrast, the most common way to currently quantify element transfer from soils into plants is relatively simple, using an empirical soil-to-plant transfer factor (TF). This practice is based on theoretical assumptions that have been previously shown to not generally be valid. Using field data on concentrations of 61 basic elements in spring barley, soil and pore water at four agricultural sites in mid-eastern Sweden, we quantify element-specific TFs. Our aim is to investigate to which extent observed element-specific uptake is consistent with TF model assumptions and to which extent TF's can be used to predict observed differences in concentrations between different plant parts (root, stem and ear). Results show that for most elements, plant-ear concentrations are not linearly related to bulk soil concentrations, which is congruent with previous studies. This behaviour violates a basic TF model assumption of linearity. However, substantially better linear correlations are found when weighted average element concentrations in whole plants are used for TF estimation. The highest number of linearly-behaving elements was found when relating average plant concentrations to soil pore-water concentrations. In contrast to other elements, essential elements (micronutrients and macronutrients) exhibited relatively small differences in concentration between different plant parts. Generally, the TF model was shown to work reasonably well for micronutrients, whereas it did not for macronutrients. The results also suggest that plant uptake of elements from sources other than the soil compartment (e.g. from air) may be non-negligible.
污染物在各种可食用植物部分中的浓度将有害物质从污染地区转移到动物和人类体内。因此，准确预测植物对元素的吸收具有重要意义。所涉及的过程包含许多相互作用的因素，因此很复杂。相比之下，目前定量从土壤中转移到植物中的元素的最常见方法相对简单，使用经验土壤-植物转移因子 (TF)。这种做法基于先前已证明通常不成立的理论假设。利用瑞典中东部四个农业地点的春大麦、土壤和孔隙水中 61 种基本元素的田间数据，我们量化了元素特异性 TF。我们的目的是调查观察到的元素特异性吸收在多大程度上符合 TF 模型假设，以及 TF 在多大程度上可以用于预测不同植物部分（根、茎和穗）之间浓度的差异。结果表明，对于大多数元素，植物穗部浓度与土壤总量浓度不成线性关系，这与以前的研究一致。这种行为违反了 TF 模型线性的基本假设。然而，当使用整个植物的加权平均元素浓度进行 TF 估计时，会发现与线性相关度更高的线性关系。当将平均植物浓度与土壤孔隙水浓度相关联时，会发现线性行为的元素数量最多。与其他元素相比，必需元素（微量元素和大量元素）在不同植物部分之间的浓度差异相对较小。一般来说，TF 模型对微量元素的工作效果相当好，而对大量元素则不然。结果还表明，植物从土壤以外的来源（例如空气）吸收元素可能不可忽视。
