Data/hora: 02/06/2024 06:34:16

Provedor de dados: 	63	
País: 	Brazil	
Título: 	Routine soil testing to monitor heavy metals and boron	
Autores: 	Abreu,Cleide Aparecida de; van Raij,Bernardo; Abreu,Mônica Ferreira de; González,Antonio Paz.	
Data: 	2005-12-01	
Ano: 	2005	
Palavras-chave: 	Soil analyses; Micronutrients; Heavy metals; Deficiency; Toxicity; Interpretation limits.	
Resumo: 	Microelements are an important issue in agriculture, due to their need as micronutrients for plants and also to the possibility of the build-up of toxic levels for plants and animals. Five micronutrients (B, Cu, Fe, Mn, and Zn) are routinely determined in soil analysis for advisory purposes. Other four elements (Cd, Cr, Pb, and Ni) are considered environmentally important heavy metals in farmland soils. Thus high contents of these metals in cropland might go eventually unnoticed. In this paper we present an approach that can be used to monitor the contents of the nine elements in farmland soils using advisory soil testing. A total of 13,416 soil samples from 21 Brazilian states, 58% of them from the state of São Paulo, sent by farmers were analyzed. Boron was determined by hot water extraction and the other metals were determined by DTPA (pH 7.3) extraction. The ranges of content, given in mg dm-3 soil, were the following: B, 0.01-10.6; Cu, 0.1-56.2; Fe, 0.5-476; Mn, 1-325; Zn, 1-453; Cd, 0.00-3.43, Cr, 0.00-42.9; Ni, 0.00-65.1; Pb, 0.00-63.9. The respective average values for São Paulo were: B-0.32; Cu-2.5; Fe-36; Mn-16; Zn-4.8; Cd-0.02; Cr-0.03; Ni-0.18; Pb-0.85. For other states the results are in the same ranges. The higher values are indicative of anthropogenic inputs, either due to excess application of fertilizers or to industrial or mining activities. The conclusion is that massive chemical analysis of farmland soil samples could serve as a database for indicating potential micronutrient deficiency and excesses or heavy metal buil-up in croplands, allowing preventive actions to be taken.	
Tipo: 	Info:eu-repo/semantics/article	
Idioma: 	Inglês	
Identificador: 	http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162005000600009	
Editor: 	São Paulo - Escola Superior de Agricultura "Luiz de Queiroz"	
Relação: 	10.1590/S0103-90162005000600009	
Formato: 	text/html	
Fonte: 	Scientia Agricola  v.62 n.6 2005	
Fonte: 	info:eu-repo/semantics/openAccess