Data/hora: 22/09/2024 22:11:16

Biblioteca(s): 	Embrapa Pantanal.	
Data corrente: 	27/01/1997	
Data da última atualização: 	03/04/2017	
Autoria: 	ALVES, B. J. R.; BODDEY, R. M.; URQUIAGA, S. S.	
Título: 	A rapid and sensitive flow injection technique for the analysis of ammonium in soil extracts.	
Ano de publicação: 	1993	
Fonte/Imprenta: 	Communications in Soil Science and Plant Analysis, v.24, n.3/4, p.277-284, 1993.	
Idioma: 	Inglês	
Conteúdo: 	The steam distilation technique for the quantification of soil mineral nitrogens is not well adapted to estimate very low levels of NH4+ and NO3- such as those found in tropical pastures. In this paper we describe a flow injection analysis (FIA) technique for the direct estimation of soil ammonium in potassium chloride extracts. The technique is based on the salicylate/hypochloride colorimetric reaction with the resulting colouration read at 647 nm. The speed of the reaction was increased by immersing the reaction coils in a water bath maintained at 70C. The technique was capable of accurately quantifying ammonium to concentrations as low as 0.05 mg NH4+-N/L (equivalent to 0.25 mg NH4+-N/g dry soil) and sample thoughputs of at least 60 samples per hour could be achieved. It was found that amino acids whould also give a positive colorimetric reaction but that in the ten tropical soils examined this was not a significant source of error.	
Palavras-Chave: 	Ammonium; Amonio; Analysis.	
Thesagro: 	Análise; Nitrogênio; Nutrição; Solo.	
Thesaurus Nal: 	nitrogen; nutrition; soil.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Pantanal (CPAP)	
Exemplares: 	CPAP - (33628-1) - ADC - SP - PP - SP15120 -  - 15120 - DIS