Department of Soil Science, Federal University of Lavras, University Campus, Lavras, MG, 37200-000, Brazil.
Department of Rural Engineering, Center of Agricultural Sciences, Federal University of Santa Catarina, Rod. Admar Gonzaga 1346, Florianópolis, SC, 88034-000, Brazil.
Environ Geochem Health. 2020 Oct;42(10):3281-3301. doi: 10.1007/s10653-020-00572-9. Epub 2020 Apr 25.
This study aims to evaluate available Cu and Zn levels in soil and related in soil organic matter (SOM) fractions (fulvic acids-FA, humic acids-HA, and humins-HU) after 10 years of application of pig slurry (PS) and pig deep litter (PL). Soil samples were collected from an experiment with black oat/corn succession under no-tillage in southern Brazil. The treatments consisted of fertilization of 90 and 180 kg N ha applied as PS and PL from 2002 to 2012 and a control treatment without any fertilization. SOM chemical fractionation was performed in air-dried samples. Copper and Zn concentrations were analyzed in soil (total, EDTA- and CaCl-extracted) and in SOM fractions. The amount of Cu and Zn (in mol) related to each fraction of SOM (Cu/C and Zn/C molar ratios) was established. The applications of PS and PL promoted the accumulation of total and available Cu and Zn, especially in the PL180 treatment. The highest amount of Zn was found with HU, while for Cu both HA and HU were important retention compartments. The highest Cu/C, Cu/C and Cu/C ratios were found with the addition of PL. Increases in Zn/C ratio were found mainly in FA fraction. The high levels of Cu and Zn obtained in the HCl-extracted SOM fraction suggest that a considerable part is bound to SOM and clay minerals with low energy. However, the SOM is an important source of metal adsorption in soils with swine manure application.
本研究旨在评估猪粪（PS）和猪深垫料（PL）施用 10 年后土壤及相关土壤有机质（SOM）各组分（富里酸-FA、腐殖酸-HA 和胡敏素-HU）中的 Cu 和 Zn 含量。土壤样本取自巴西南部免耕黑燕麦/玉米轮作试验。处理包括 2002 年至 2012 年以 PS 和 PL 形式施 90 和 180 kg N/ha，以及不施肥的对照处理。风干样本进行 SOM 化学分级。分析土壤（全量、EDTA 和 CaCl2 提取量）和 SOM 各组分中的 Cu 和 Zn 浓度。建立与 SOM 各组分（Cu/C 和 Zn/C 摩尔比）相关的 Cu 和 Zn 量（以摩尔计）。PS 和 PL 的施用促进了总 Cu 和 Zn 以及有效态 Cu 和 Zn 的积累，尤其是在 PL180 处理中。HU 中发现 Zn 含量最高，而对 Cu 来说，HA 和 HU 都是重要的保留部位。PL 施用量最高的 Cu/C、Cu/C 和 Cu/C 比值。FA 组分中的 Zn/C 比值增加。HCl 提取 SOM 组分中获得的高 Cu 和 Zn 水平表明，相当一部分与 SOM 和低能粘土矿物结合。然而，在施用猪粪的土壤中，SOM 是金属吸附的重要来源。
