Area of Soil Science and Soil Chemistry, E.T.S. Ingenierías Agrarias, University of Valladolid, Avda. de Madrid 57, 34004 Palencia, Spain; Sustainable Forest Management Research Institute, University of Valladolid-INIA, Avda, Madrid 44, 34071 Palencia, Spain.
Area of Soil Science and Soil Chemistry, E.T.S. Ingenierías Agrarias, University of Valladolid, Avda. de Madrid 57, 34004 Palencia, Spain.
Sci Total Environ. 2018 Nov 15;642:374-382. doi: 10.1016/j.scitotenv.2018.06.051. Epub 2018 Jun 12.
The main aim of this research was to assess the effects of municipal solid waste compost (MSWC) addition to a burnt and unburnt calcareous soil, on the distribution of soil P forms in particle-size and extractable fractions. Three MSWC doses (1, 2 and 4% w/w) were added to burnt and unburnt soil samples and were incubated for 92 days at 29 °C and 75% of field capacity moisture. A particle-size fractionation followed by a sequential P extraction procedure was carried out. The burnt soil showed significantly lower concentrations of organic P forms (P) and significantly higher concentrations of stable P forms than the unburnt soil. Besides, in both burnt and unburnt soils, most P-forms presented higher concentrations in the clay fractions than in the sand and silt fractions, possibly due to the different proportions of microbial synthesized and plant-derived substances in the different particle-size fractions. Finer fractions of MSWC showed higher total P and P concentrations than coarser fractions. Our results showed that the highest dose of MSWC` was the most effective one for the rehabilitation of the burnt soil. MSWC amendment also caused an increase in soil P availability in the unburnt soil which initially contained relatively low levels of P. During the incubation process, a high proportion of organic P contained in the MSWC was mineralized into inorganic P forms. These forms were precipitated with Ca cations which are very abundant in these calcareous soils, significantly increasing the P fraction extracted by HCl in both amended soils. Hence, adding compost to the soil involved an increase in the available P reservoir in the long term. The combination of particle-size fractionation, chemical sequential extraction and incubation experiments can be a valuable tool for splitting soil phosphorus into different fractions regarding their availability in relation to short and long-term transformations in soil.
本研究的主要目的是评估添加城市固体废物堆肥（MSWC）到燃烧和未燃烧的钙质土壤中对土壤磷形态在颗粒大小和可提取分数中的分布的影响。将三种 MSWC 剂量（1、2 和 4%w/w）添加到燃烧和未燃烧的土壤样品中，并在 29°C 和 75%田间持水量下培养 92 天。进行了颗粒大小分级，然后进行了顺序磷提取程序。燃烧土壤中有机磷（P）的浓度明显较低，稳定磷形式的浓度明显较高，而未燃烧土壤则相反。此外，在燃烧和未燃烧的土壤中，大多数磷形态在粘土分数中的浓度高于在砂和粉砂分数中的浓度，这可能是由于不同颗粒大小分数中微生物合成和植物衍生物质的比例不同。MSWC 的较细分数比较粗分数具有更高的总磷和 P 浓度。我们的结果表明，MSWC 的最高剂量是修复燃烧土壤最有效的方法。MSWC 改良还增加了未燃烧土壤中磷的有效性，因为未燃烧土壤最初含有相对较低水平的磷。在培养过程中，MSWC 中所含的大量有机磷被矿化成无机磷形态。这些形态与这些钙质土壤中非常丰富的 Ca 阳离子一起沉淀，显著增加了两种改良土壤中用 HCl 提取的磷分数。因此，长期来看，向土壤中添加堆肥会增加有效磷储量。颗粒大小分级、化学顺序提取和培养实验的组合可以是一种有价值的工具，可以将土壤磷分为不同的分数，以反映其在土壤短期和长期转化中的可用性。
