Abstract:
Phosphorus (P) is one of the essential elements for life on Earth. As a major nutrient it is needed for healthy growth both in plants and living organisms. Although the abundance of P in the Earth\'s upper continental crust is relatively high (655 mg/kg), many soil types are poor in available phosphorus. The main natural factors controlling the availability of P in soil are pH, mineralogy, and formation of insoluble complexes with Al and Fe under acidic, and with Ca and Mg under alkaline soil conditions. Superimposed weathering processes and climate contribute strongly to P mobility and availability. Additionally, a large fraction of total soil P is in organic forms, which are not directly available to plants. Phosphorus is a major component in fertilisers and thus a significant source of anthropogenic P in soil and water. In the agricultural soil samples that were collected during the Geochemical Mapping of Agricultural and grazing land Soil (GEMAS) project, the total P concentrations (XRF, median 786 m/kg) are only slightly higher than those extracted by hot aqua regia (AR, median 653 mg/kg), while the median concentration in the weak MMI® cold extraction is as low as 4.1 mg/kg. The AR results show very low P concentrations over the coarse-grained sandy sediments of the last glaciation in central and northern Europe and in calcareous soil. The southern limit of the last glaciation is visible as a concentration break on the geochemical maps. In general, north-eastern and north-western Europe are marked by high P values, probably related to cold and humid climate and enrichment in humus-rich coastal soil. The spatial distribution of P at the continental-scale is dominated by geogenic and climatic factors, and the anthropogenic influence is difficult to assess and quantify.
摘要:
磷(P)是地球上生命的基本要素之一。作为一种主要的营养素,它是植物和生物体健康生长所必需的。尽管地球上大陆地壳中磷的丰度相对较高(655mg/kg),许多土壤类型缺乏有效磷。控制土壤中磷有效性的主要自然因素是pH值,矿物学,在酸性条件下与Al和Fe形成不溶性络合物,以及在碱性土壤条件下的Ca和Mg。叠加的风化过程和气候对磷的流动性和可用性有很大贡献。此外,土壤总磷的很大一部分是有机形式,不能直接提供给植物。磷是肥料中的主要成分,因此是土壤和水中人为磷的重要来源。在农业和放牧土地土壤地球化学制图(GEMAS)项目期间收集的农业土壤样品中,总磷浓度(XRF,中位数786米/千克)仅略高于热王水提取的(AR,中位数653mg/kg),而弱MMI®冷提取中的中值浓度低至4.1mg/kg。AR结果表明,中欧和北欧以及钙质土壤中最后一次冰川的粗粒沙质沉积物中的P浓度非常低。最后一次冰川的南部界限在地球化学图上可见为浓度突变。总的来说,东北和西北欧洲的P值较高,可能与寒冷潮湿的气候和富含腐殖质的沿海土壤有关。P在大陆尺度上的空间分布主要受地质和气候因素的影响,人为影响难以评估和量化。