Data/hora: 19/06/2024 02:43:14

Biblioteca(s): 	Embrapa Pantanal.	
Data corrente: 	27/01/1997	
Data da última atualização: 	03/04/2017	
Autoria: 	AMATO, M.; LADD, J. N.	
Título: 	Studies of nitrogen immobilization and mineralization in calcareous soils- V. Formation and distribution of isotope-labelled biomass during decomposition of 14C- and 15N-labelled plant material.	
Ano de publicação: 	1980	
Fonte/Imprenta: 	Soil Biology and Biochemistry, v.12, p.405-411, 1980.	
Idioma: 	Inglês	
Conteúdo: 	Medicago littoralis leaf material, labelled with 14C and 15N, and C:N ratio 8.7:1, decomposed rapidly in a calcareous soil. One half of the plant-C and two thirds of the plant-N remained in the soi as organic residues after 34 days. The rates of decomposition and the changes in the distribution of organic -14C and -15N resudies followed similar patterns. Incorporation of 14C and 15N into microbial cells, formed during plant breakdown, reached a maximum after 62 days. At this time the microbial biomass accounted for 21.9 and 23.3%, respectively, of residual organic -14C and -15N. Thereafter, the amounts of isotope-labelled biomass decreased with the percentage decrease slightly exceeding that of the total labelled soil residues. During plant decomposition, changes occurred in the concentration of organic -14C and -15N in some  of the soil components, these having been fractionated according to density and particle size. Especially evident was the rapid and extensive decrease of labelled material from the fine caly-size components. This was partly due to the decrease in the biomass -14C of this fraction. Changes in biomass -14C of some physical fractions were approximately reflected by changes in their numbers of viable microorganisms.	
Palavras-Chave: 	Decomposition; Plant.	
Thesagro: 	Biomassa; Decomposição; Mineralização; Nitrogênio; Planta.	
Thesaurus Nal: 	biomass; Medicago littoralis; mineralization; nitrogen.	
Categoria do assunto: 	--	
Registro original: 	Embrapa Pantanal (CPAP)	
Exemplares: 	CPAP - (33615-1) - ADD - SP - PP - SP15107 -  - 15107 - DIS