Residual effects of potentially toxic elements from the fertilizing: quality of agricultural products

Author(s)

Luiz Henrique Marcandalli

• Document type: Master's Dissertation
• Press: Piracicaba.
• Institution: Universidade de São Paulo (USP). Centro de Energia Nuclear na Agricultura (CENA/STB)
• Defense date: 2012-10-29

Examining board members

Cassio Hamilton Abreu Junior; Salatier Buzetti

• Advisor: Cassio Hamilton Abreu Junior

Abstract

Due to the presence of contaminants (Potentially Toxic Elements - EPT) in fertilizers, is the source material of PRs or the use of products which contain high levels of heavy metals, has caused much controversy and discussion. The knowledge of the fractions of the elements in the soil can indicate the availability thereof to the plants and finally subsidize fertilizer practice in a safer way. This project aimed to: (1) evaluate the dry matter production and determine the levels of P (Ni and Zn) and EPT (Cr, Cd, Pb) in the edible portion of the lettuce (leaves) and radish (roots ) in response to fertilization with phosphorus sources and zinc applied in previous crop (residual effect), (2) assess the nutritional status of lettuce and radish in relation to nutrients P and Zn fertilization under the effect of phosphorus sources and Zinc applied in previous crop (residual effect): (3) determining the residue content of available P (resin), trace elements (Ni, Zn) and EFA (Cr, Cd, Pb) extracted by Mehlich-1, DTPA, CaCl2 0 , 01 mol L-1 solution and organic acids in soils fertilized with phosphorus sources and zinc after growing lettuce and radish. Residual crops are developed with the lettuce and radishes in a greenhouse using two contrasting soils as the clay content. Treatments were applied during the cultivation of upland rice and thus will be conducted only fertilizers and basic coverage. Treatments are divided as follows: three sources of Zn (byproduct, commercial fertilizer obtained from acidulation by product and a mixture of reagents for analysis) and three sources of P (phosphate rock from Togo, superphosphate obtained by acidulation of rock and Togo a mixture of reagents for analysis) at doses of 0, 2.5, 5, 10 and 20 times the recommended dose (average of 4 kg Zn and 90 kg P2O5 per ha). The analyzes carried out on the ground with different extractants and analysis of leaves (lettuce) and roots (radish) to determine the levels of potentially toxic elements present in the soil and edible parts can be concluded that the levels of phosphorous in soil and zinc increased with increasing doses of the use of these elements in the Oxisol (LVA) and Oxisol (LV), the use of organic acid solution extractants, Mehlich-1 and DTPA, led to an increased availability of metals in soil; doses increasing phosphorus elevated levels of cadmium in the soil available, but this increase did not show significant differences in the edible parts, the use of different sources and levels of phosphorus and zinc showed no significant differences in the production of plant material cultures; doses of zinc elevated levels of lead in the soil available, however this increase was not observed in the edible parts of crops, chromium has not changed with the different fertilizer levels (AU)

• FAPESP's process: 09/13356-2 - Residual outcome of toxic heavy metals from fertilizers: quality of agricultural products
• Grantee: Luiz Henrique Marcandalli
• Support Opportunities: Scholarships in Brazil - Master