Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), University Bayreuth, 95440, Bayreuth, Germany.
Center for Permafrost (CENPERM), University of Copenhagen, DK-1350, Copenhagen, Denmark.
Sci Rep. 2019 Jan 24;9(1):449. doi: 10.1038/s41598-018-37104-6.
Phosphorus availability in soils is an important parameter influencing primary production in terrestrial ecosystems. Phosphorus limitation exists in many soils since a high proportion of soil phosphorus is stored in unavailable forms for plants, such as bound to iron minerals or stabilized organic matter. This is in spite of soils having a high amount of total soil phosphorus. The feasibility of silicon to mobilize phosphorus from strong binding sites of iron minerals has been shown for marine sediments but is less well studied in soils. Here we tested the effect of silicon on phosphorus mobilization for 143 Artic soils (representing contrasting soil characteristics), which have not been affected by agriculture or other anthropogenic management practices. In agreement with marine studies, silicon availabilities were significantly positive correlated to phosphorus mobilization in these soils. Laboratory experiments confirmed that silicon addition significantly increases phosphorus mobilization, by mobilizing Fe(II)-P phases from mineral surfaces. Silicon addition increased also soil respiration in phosphorus deficient soils. We conclude that silicon is a key component regulating mobilization of phosphorous in Arctic soils, suggesting that this may also be important for sustainable management of phosphorus availability in soils in general.
土壤中的磷有效性是影响陆地生态系统初级生产力的一个重要参数。由于土壤中的大部分磷以植物难以利用的形式存在，如与铁矿物结合或稳定的有机质结合，因此许多土壤都存在磷限制。尽管土壤中总磷含量很高。硅从铁矿物的强结合位点中动员磷的可行性已在海洋沉积物中得到证实，但在土壤中的研究较少。在这里，我们测试了硅对 143 个北极土壤（代表不同的土壤特性）的磷动员效果，这些土壤没有受到农业或其他人为管理实践的影响。与海洋研究一致，硅的有效性与这些土壤中的磷动员呈显著正相关。实验室实验证实，硅的添加通过从矿物表面动员 Fe(II)-P 相显著增加了磷的动员。硅的添加还增加了磷缺乏土壤中的土壤呼吸。我们得出结论，硅是调节北极土壤磷动员的关键组成部分，这表明这对于一般土壤中磷有效性的可持续管理也很重要。
