Data/hora: 01/06/2024 01:29:04

Biblioteca(s): 	Embrapa Meio Ambiente.	
Data corrente: 	10/02/2012	
Data da última atualização: 	07/08/2012	
Autoria: 	MARKEWITZ, D.; FIGUEIREDO, R. de O.; CARVALHO, C. J. R. de; DAVIDSON, E. A.	
Afiliação: 	DANIEL MARKEWITZ, University of Georgia; RICARDO DE OLIVEIRA FIGUEIREDO, CNPMA; CLAUDIO JOSE REIS DE CARVALHO, CPATU; ERIC A. DAVIDSON, Woods Hole Research Center.	
Título: 	Soil and tree response to P fertilization in a secondary tropical forest supported by an Oxisol.	
Ano de publicação: 	2011	
Fonte/Imprenta: 	Biology and Fertility of Soils, Berlin, v. 48, 2011.	
Idioma: 	Inglês	
Conteúdo: 	Abstract: Abstract Mature tropical forests are considered to be P
limited and to cycle P efficiently. Whether P limitations
are significant in younger secondary tropical forests, how-
ever, remains largely unexplored. This study evaluated P
limitation by observing the P fertilizer response of a natu-
rally regenerated 24-year-old forest and its soil. In February
1999, six 20×20-m plots were established in secondary
forest in the Brazilian Amazon. After 1 year of pre-
treatment tree measurements, 50 kg Pha-1 was applied in
January 2000 and again in January 2001. Soil sorption of P
was relatively low (~100 micrograms g-1) in the surface 0–20 cm
while sorption increased to ~180 micrograms g-1 at 20–50 cm and
approached ~500 micrograms g-1 for the 50- to 200-cm layers. Soil P
in 0–10 cm, measured as sequentially extractable fractions
(resin, HCO3-Pi, NaOH-Pi, NaOH-Po, and 1 M HCl), in-
creased shortly after fertilization and could account for
nearly all the 50 kg Pha-1 added at each date. During the
 
following 6 years, soil P in fertilized plots declined in all
pools other than resin P, and by June 2006, concentrations
returned to pre-fertilization levels. Despite the increase in
extractable P with fertilization, increased tree growth was
not detected from stand age 25 to 31 years. It appears that
during secondary forest succession at this site, the forest P
cycle was conservative so as to maintain available P at a
sufficient concentration to meet forest P demands.	
Palavras-Chave: 	Fracionamento de fósforo; Limitação de fósforo; Sorção de fósforo.	
Thesagro: 	Fertilidade do solo; Floresta secundária; Floresta tropical; Fósforo.	
Thesaurus Nal: 	Amazonia; Phosphorus fertilizers; Rain forests; Secondary forests; Soil fertility.	
Categoria do assunto: 	P Recursos Naturais, Ciências Ambientais e da Terra	
Registro original: 	Embrapa Meio Ambiente (CNPMA)	
Exemplares: 	CNPMA - (10618-1) - UPC - AP - DD -  -  -  - DIS