Pinto Edgar, Almeida Agostinho A, Ferreira Isabel M P L V O
REQUIMTE/Departamento de Ciências Químicas, Laboratório de Bromatologia e Hidrologia da Faculdade de Farmácia da Universidade do Porto, Portugal.
REQUIMTE/Departamento de Ciências Químicas, Laboratório de Química Analítica da Faculdade de Farmácia da Universidade do Porto, Portugal.
Ecotoxicol Environ Saf. 2015 Mar;113:418-24. doi: 10.1016/j.ecoenv.2014.12.026. Epub 2014 Dec 23.
The influence of soil properties on the phytoavailability of metal(loid)s in a soil-plant system was evaluated. The content of extractable metal(loid)s obtained by using different extraction methods was also compared. To perform this study, a test plant (Lactuca sativa) and rhizosphere soil were sampled at 5 different time points (2, 4, 6, 8 and 10 weeks of plant growth). Four extraction methods (Mehlich 3, DTPA, NH4NO3 and CaCl2) were used. Significant positive correlations between the soil extractable content and lettuce shoot content were obtained for several metal(loid)s. The extraction with NH4NO3 showed the higher number of strong positive correlations indicating the suitability of this method to estimate metal(loid)s phytoavailability. The soil CEC, OM, pH, texture and oxides content significantly influenced the distribution of metal(loid)s between the phytoavailable and non-phytoavailable fractions. A reliable prediction model for Cr, V, Ni, As, Pb, Co, Cd, and Sb phytoavailability was obtained considering the amount of metal(loid) extracted by the NH4NO3 method and the main soil properties. This work shows that the analysis of rhizosphere soil by single extractions methods is a reliable approach to estimate metal(loid)s phytoavailability.
评估了土壤性质对土壤 - 植物系统中金属（类金属）植物有效性的影响。还比较了使用不同提取方法获得的可提取金属（类金属）的含量。为开展这项研究，在5个不同时间点（植物生长2、4、6、8和10周）采集了受试植物（生菜）和根际土壤。使用了四种提取方法（Mehlich 3、DTPA、NH4NO3和CaCl2）。几种金属（类金属）的土壤可提取含量与生菜地上部分含量之间存在显著正相关。NH4NO3提取显示出较高数量的强正相关，表明该方法适用于估算金属（类金属）的植物有效性。土壤阳离子交换量、有机质、pH值、质地和氧化物含量显著影响了金属（类金属）在植物可利用和不可利用部分之间的分布。考虑到NH4NO3方法提取的金属（类金属）量和主要土壤性质，获得了Cr、V、Ni、As、Pb、Co、Cd和Sb植物有效性的可靠预测模型。这项工作表明，通过单一提取方法分析根际土壤是估算金属（类金属）植物有效性的可靠方法。
