Effect of different amendments on trace metal bioavailability in agricultural soils and metal uptake on lettuce evaluated by Diffusive Gradient in Thin Films

In this study, we have investigated the effect of two different organic amendments on trace metal transfer from soils to crops. Agricultural soils were mixed with (i) biochar (BC) at two levels (3% and 6%, w/w), and (ii) compost at one level (30%, w/w). Lettuce (Lactuca sativa L.) was planted, and a...

ver descrição completa

Detalhes bibliográficos
Autores: Turull, Marta, Fontàs, Clàudia, Díez, Sergi
Formato: artículo
Estado:Versión aceptada para publicación
Fecha de publicación:2020
País:España
Recursos:Consejo Superior de Investigaciones Científicas (CSIC)
Repositorio:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/225476
Acesso em linha:http://hdl.handle.net/10261/225476
Access Level:acceso abierto
Palavra-chave:Agricultural soils
Organic amendments
DGT
Diffusive gradient in thin film
Chelex-100
Descrição
Resumo:In this study, we have investigated the effect of two different organic amendments on trace metal transfer from soils to crops. Agricultural soils were mixed with (i) biochar (BC) at two levels (3% and 6%, w/w), and (ii) compost at one level (30%, w/w). Lettuce (Lactuca sativa L.) was planted, and at the end of growth, trace metals (Cd, Cr, Cu, Ni, Pb and Zn) were analysed in both plants and soil. To evaluate the bioavailability and mobility of labile trace metals, different methodologies were used, such as the diffusive gradient in thin film (DGT) technique, BCR sequential extraction and pore water extraction. It has been observed that the lettuces grown in soils with added compost, the amounts of Cd, Cr, Cu and Pb was 1.7, 2.4, 1.3 and 3.7 times lower, respectively, than those found in lettuces planted in soils with no amendment. Moreover, the addition of 3% of BC reduced the uptake of Cr (24%) whereas a 6% of BC reduced Cr (55%) and Pb (50%) levels. Using the DGT technique in soils with different organic matter (OM) content, labile fractions of Cr, Cu and Pb were successfully correlated (p<0.05) with lettuce total metal concentrations. In conclusion, BCR sequential extraction and DGT method have shown similar efficiency in front other methodologies, although it seems that DGT-methodology is faster and more cost-effective method than sequential extraction for predicting metal uptake by plants.